run mud pump with one geneator and old scr house for sale

Our DC systems are based on an industry standard design and inherit the dependability, reliability and ease of maintenance of this concept. Our AC systems are built around ABB drive and control technology. Enhanced systems, PLC control and serial links to the Drill Floor are available to reduce rig-uptime for land rigs.

We also have the expertise to source replacements for obsolete spare parts, and re-engineer older systems with new equipment, including adding extra SCR sections for third Mud Pumps or Top Drives, and additional generator sections for additional rig power.

We are able to provide training either on-site using your existing equipment, or from our base in London, England. As well as providing in-depth knowledge and support for SCR and generator control systems.

As to the electric system, we compared the DC drive rigs and AC converterdrive rigs deeply, we recommend AC (AC-VFD-AC)converter drive rigs due to the following advantage of AC Converter drive rigs.

2， It has the limitation function of Torque and rotation speed, strong overload protection could avoid the broken of drill pipes and other main parts.

Being a manufacturer of power generation controls and high power electronic variable speed driveequipment, Joton must maintain qualified personnel to ensure our products are put into service correctly, and effectively. The wide range of specially designed power equipment sold, designed and manufactured by Joton means that our startup and service personnel must be versatile in the full scope of their knowledge.

This can be of great benefit to customers that have not purchased any of our manufactured products. Our technical staff has knowledge in the following areas and can provide technical Oilfield service in these areas if you have equipment that is shut down from an unresolved failure, or just need to ensure the system is operating correctly.

• The Power Control Room (SCR House) will be Top Lift Only, and be equipped with roof mounted handrails and an access ladder mounted on the outside (just as the original)

• Includes power and control provisions for an Eddy Brake (Baylor Brake) to include an MCC feed, and internal cables. Our proposal does not include the actual Brake Controller or the transformers.

• The standard electronic engine/generator controller uses a 0-200 mA signal to control the engines direct fuel rack and thus its engine speed. If necessary, a 4-20 mA engine speed signal conversion kit is available for engines that cannot use the 0-200 mA signal.

• All power and control cable terminations are intended to be “hard-wired” through ROX frames. No plug boards will be used. Will include the ROX frames only.

4- Model 1500 I-DRIVE SCR Drive Cubicles each equipped with electronic controllers, primary and secondary assignments, and 600V feeder circuit breaker switches

4 - Generator Control Cubicles each equipped with electronic controllers (metering module, governor module, and voltage regulator module) and 600V feeder circuit breaker

E. One (1) Low Voltage Distribution and Lighting Distribution Panel with 3- pole, 2-pole, and 1-pole breakers as required (will match the existing unit but may be relocated to a new location in the house.

F. One (1) Power Control Room outdoor, weatherproof, insulated, mobile steel building equipped for Top Lifting Provisions. The building will contain the above wired and tested equipment.

* KW/KVA limiting circuitry monitors the available power and compares it against the KW/KVA in use, so that the power consumed by the SCR system does not exceed the available power on the line.

* Control power will be 120 VAC for best contact integrity and line noise immunity. The system will be provided with a control power transformer to provide control for standard contactor logic and alarm function. Each SCR converter section will be assignable to two (2) loads. Assignment switching will provide 100% redundancy in case of converter or load failure.

* All logic functions will be provided according to customer specifications and necessary safety functions. There will be two (2) SPST load interrupting main contactors for each assignment.

5) I-Drive module is a standard unit; interchangeable on any system, on shore/off-shore, single motor, two motor operation and series or shunt motors.

I-Drive Power Limiting protects the diesel engine/generator set(s) from dropping "Off Line" due to an overloading. When maximum KW or KVA capacity has been reached, the system "phases back" the outputs of the SCR drives connected to the AC Buss, and thus prevents the generator sets from dropping off line due to an overload.

The I-Drive SCR Control Module accepts four different current limit settings, which corresponds to the four possible assignments of the SCR drive. The I-Drive SCR DC cardrack test panel has four potentiometers where the Current Limits are set. The current limit settings are a separate module from the D/C module which allows changing the D/C module without resetting current limits.

The I-Drive Firing Circuit Regulator works in conjunction with the AC Buss Phase Sensing and the Six Gating Pulse circuits. The SCR firing pulses are referenced to the Three AC Lines, and timed to trigger the respective SCR"s at the correct instant.

There are six firing pulses (each spaced 60 degrees from the previous) in each cycle and all are adjusted simultaneously by the firing enable circuit to get the correct SCR firing angle.

This feature allows the I-Drive SCR drive to deliver more current for a short period of time than what is preset with the current limit Calibration as set on the DC cardrack test panel. This feature can be used in situations where high current is needed for short periods of time, I.E. for a drawworks motor. The amount of overcurrent allowed is set at the Timed-Overcurrent Module, from 110% to 130% of the present current limit for approximately 60 seconds. After the 60 seconds period, the current will revert to the normal current limit as set at on the I-Drive DC cardrack test panel so as not to damage or overheat the SCR bridge.

1. Over-temperature: When the SCR Blower is lost or the SCR house internal ambient temperature rises to an unacceptable level so that proper cooling of the SCR’s is not possible, a set of thermo-switches, mounted on the SCR bridge heatsinks detect when the temperature goes above 70 degrees C and signals an alarm condition

2. Blown Fuse: The SCR bridge has a set of semi¬conductor fuses for the protection of the SCR"s. If any of the fuses open, the FFAS (fuse failure alarm signal) is activated (isolated contact closure) and the firing pulses to the SCR bridge are automatically inhibited

All the controls ARE interlocked. If the bay is re-assigned during power on, the bays shut down and will not restart until their respective throttles have been returned to the ZERO (off) position. This includes the foot throttle.

The I-Drive SCR drive is of modular design, compact, NEMA type 1 A construction WITH DRIPSHIELDS, front access only. The D.C. control module contains the circuitry necessary to control the SCR Bridge’s output. The module is interchangeable between all I-Drive SCR systems. The module is furnished with no adjustments necessary. The module is easily disconnected for replacement should the need arise. This makes for a minimum of “down-time” should a failure occur.

The I-Drive SCR Bay cooling is assisted by a squirrel cage blower forcing air in the direction from bottom to top of the cabinet. Air is drawn in through a filter in the lower section of the front door. It then proceeds over the contactors, DC buss, and into the blower intake. The blower’s output airflow goes directly into the plenum below the SCR bridge, into the bridge heatsinks (the point of the most air flow resistance), out the top of the bridge, upward past the circuit breaker and AC buss, and out the top of the cabinet.

The I-Drive SCR Bridge is composed of three (3) identical and interchangeable modules (Phase Cells). Each Phase Cell has an AC input flag, a minus DC output flag, and a plus DC output flag. In the Phase Cells the discrete SCR devices have heatsinks on both sides. Thermodynamics proves that this allows the SCR devices to operate at a lower temperature than single sided “bricks” for the same device current. The lower the operating temperature, the more reliable the SCR device is. The system is designed for low maintenance and to operate in ambient air temperature up to 50 degrees C without air conditioning.

The I-Drive drawworks dynamic brake will slow the drawworks motors from full speed within eight to ten seconds after the foot throttle is released. The power of the free wheeling motor is fed back into a resistor bank. During normal operation the dynamic brake system is non-operative, and the drawworks is either OFF or operating at the desired cathead speed. If however, at any time the motor speed is higher than the DW throttle speed setting, and the foot throttle is OFF, the dynamic brake system is actuated, reducing the motor speed to the DW throttle setting.

The I-Drive foot throttle is constructed of rugged stainless steel throughout; built to withstand the environment normally encountered on the rig floor.

The I-Drive Drillers Console will be NEMA type 4X construction of #316 stainless steel1 outdoor weather proof and provided with air purge/pressurization fittings to allow use in a Class 1, Division 2 hazardous area. All assignment switches, hand throttles and controls will be front mounted on the door. All meters, instruments and annunciators will be mounted behind the front door with a safety glass view window provided to view the meters and instruments, etc. The door will be attached with stainless steel hinges and positive latching stainless steel latches.

One set of I-Drive generator control cubicles consisting of three (3) each I- DRIVE model 1200 engine/generator control modules, breakers and related equipment for the control of three (3) each engine/generator sets and a synchronizing and ground detection cubicle.

I-Drive AC Electronic Control Section contains the AC cardrack. Three modules plug into the AC cardrack. They are the Engine Electronic Governor module, Generator Electronic Voltage Regulator module and the Metering control module. All external connections to the AC cardrack are by barrier strip (screw type).

Dynamic KW load sharing - each regulator is independent and automatically shares when placed “on line” KW sharing can be set to track within 2% of rated KW of generator.

Dynamic KVAR sharing - each regulator is independent and automatically shares when placed “on line” KVAR sharing can be set to track within 2% of rated KVAR of generator.

The HOCC System will supply power for the engine starting circuit and the pulse pick-up circuit in each generator control module. The system/operation will consist of the following.

1 – Set of Hands off cranking batteries consisting of gell cell batteries and electronically regulated battery chargers to provide cold start power for engine controls.

1 –Engine control power supply (each generator control section) to provide engine control power to each engine. Upon initial start up (cold) the batteries will supply cold power to the engine controls to allow engine starting. After the generators are online, the engine control power supply will provide control power for continuous operation. After the engine control power supply is activated, the batteries will drop out and revert to stand-by power in case of primary power supply failure.

2 Each - 800AF/800AT circuit breakers, DRAWOUT MONTED each to feed power to one (1) 1000 KVA 600/480V power transformer and interlocked so that only one can be closed at one time

Motor Control Center will be NEMA Type lA Construction, front access only with horizontal and vertical solid copper bus. Motor starters to be motor starter/circuit breaker combination type full voltage, non-reversing with 3 pole overload blocks, overload heaters, control power transformer, fuses, operating handle, and start/stop push button (or H-O-A Control) in the door.

The horizontal buss will be copper and suitably rated. The vertical buss will be will be copper and rated for 300 amps. A copper round buss will run the full length of the MCC Line-up.

The columns and ceiling framing will be constructed from structural steel. The outside steel sheeting will be fabricated from sheet steel, min. 12 ga.

The walls and roof sheeting sections will be welded together. The floor will be fabricated from three sixteenth inch thick smooth steel plate. The inside surface of the walls will be finished with a sandwich style insulating board, three eights inch thick with white pebble coating in the interior. The ceiling will be formed from inverted Tee-Bar and lay-in insulated ceiling board.

Two (2) industrial steel doors are provided on the sides with "Anti-Panic" handles for quick, easy opening. Doors open outward. Doors can be locked from the outside but can be opened from the inside even when locked.

Standard 48-inch fluorescent lights, a battery operated emergency light activated by loss of power on generator main bus, and convenience outlets for customer use will be provided.

Two (2) 7.5-Ton Self-contained air conditioning units that will maintain the inside temperatures within the design limits of the installed electrical equipment are included. The air conditioning will be supplied by a total of two units. Either unit will maintain operating temperature limits with one for a back-up. These air conditioning units will be fed from the A/C MCC. AC units will be installed on the roof.

The exterior of the building will be cleaned with a sweep blast of sand to remove scale and oxidation. The exterior coating will consist of a sub-coat of zinc rich primer, and covered with a coat of polyurethane, color white. The interior floor of the building will be covered with black colored epoxy enamel. The skid base will be primed and painted black.

NOTE - Includes one Caterpillar 12-cylinder, direct-injected, turbocharged, aftercooled diesel oilfield engine; 4 cycle, 170 mm bore x 191 mm stroke (6.7 in bore x 7.5 in stroke) with separate-circuit after- cooler and optimized for low emissions. Engine rotation is standard (counter-clockwise as viewed from flywheel end).

COOLING SYSTEM - In order to ensure compliance in use, optional or customer-supplied radiators must be capable of rejecting enough heat to allow proper operation at worst case site conditions, and also must supply 122 deg F (50 deg C) SCAC cooling water to the aftercooler inlet, with an SCAC flow rate of at least 100 GPM (379 l/m) with an ambient temperature of 86 deg F (30 deg C) and at-site conditions (including altitude considerations). Maximum allowable SCAC flow rate is 115 GPM (435 l/m). RADIATOR COOLED LAND BASED: Outlet controlled thermostat and housing. Jacket water pump, gear driven. Dual outlets: 88.9 mm O.D. (3.5 in) elbow hose connections. Aftercooler fresh water cooling pump (SCAC), gear driven centrifugal SCAC pump circuit contains a thermostat to keep the aftercooler coolant from falling below 30 deg C (85 F).

EXHAUST SYSTEM - Exhaust outlet: 292 mm I.D. (11.5 in). 12-10.5 mm dia holes EQ SP, 376 mm bolt hole dia. Shipped loose: Exhaust flexible fitting: 318 I.D. mm (12.5 in) 12-14 mm dia. holes EQ SP, 375 mm bolt hole dia. 306.6 mm tall with compressed gasket. Exhaust adapter: 297 mm I.D. to 340 mm I.D. (11.7 in to 13.4 in). 12-10.5 mm dia. holes EQ SP, 376 mm bolt hole dia. 12-13.8 mm dia. holes EQ SP, 430 mm bolt hole dia. 158.5 mm tall with compressed gasket. Weldable flange: 360 mm I.D. (14.2 in). 12-13.8 mm dia. holes EQ SP, 430 mm bolt hole dia. 17.4 mm wide with compressed gasket. Exhaust manifolds, dry. Dual turbochargers with w/c bearings.

INSTRUMENTATION - Electronic instrument panel, LH. Analog gauges with digital display data for: Engine oil pressure gauge. Engine water temperature gauge. Fuel pressure gauge. System DC voltage gauge. Air inlet restriction gauge. Exhaust temperature (prior to turbochargers) gauge. Fuel filter differential pressure gauge. Oil filter differential pressure gauge. Service meter (digital display only). Tachometer (digital display only). Instantaneous fuel consumption (digital display only). Total fuel consumed (digital display only). Engine start-stop (off, auto start, manual start, cooldown timer).

PROTECTION SYSTEM - ADEM A3 ECM monitoring system provides engine de-ration, or shutdown strategies to protect against adverse operating conditions. Selected parameters are customer-programmable. Status available on engine- mounted instrument panel and can be broadcast through the optional customer communications module or programmable relay control module(s). Initially set as follows: Safety shutoff protection, electrical: Oil pressure, water temperature, overspeed, crankcase pressure, aftercooler temperature. Includes air inlet shutoff, activated on overspeed or emergency stop. Alarms, electrical: ECM voltage, oil pressure, water temperature (low and high), overspeed, crankcase pressure, aftercooler temperature, low water level (sensor is optional attachment), air inlet restriction, exhaust stack temperature, filter differential pressure (oil and fuel). Derate, electrical: High water temperature, crankcase pressure, aftercooler temperature, air inlet restriction, altitude, exhaust temperature. Emergency stop push button, located on instrument panel. Alarm switches (oil pressure and water temperature), for connection to customer-supplied alarm panel. Unwired.

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ENSCO 71 is a Jack-Up drilling rig which was originally constructed at the Hitachi Zosen shipyard in 1982.  The original GE motor controls comprised five 1163 KVA generators and four 1800 ADC SCR units with associated auxiliary transformer feeders and jacking units. The SCRs were assignable to two 1600 HP twin-motor Mud Pumps, a twin motor 2000 HP Drawworks and a 1000 HP Rotary Table. A separate feeder drives a 1110 HP Top Drive. A fifth SCR was added by Hill Graham Controls in 1985 to power a third 1600 HP Mud Pump, which was cabled to the main busbars.

In early 2012, a decision was made to add a fifth 2500 KVA generator and an additional auxiliary transformer, to close-couple these to the main switchboard via a bus tie circuit breaker, and to include a dedicated feeder for the fifth SCR. A sixth SCR was also included in the switchboard extension to provide an alternative drive source for the third Mud Pump, effectively removing this load from the main switchboard. The switchboard extension, including full integration with the existing GE and Hill Graham equipment, was engineered and built by Zeefax.

As well as providing an extension to the main 600 V switchboard, Zeefax also designed, built and commissioned an accompanying 480 V switchboard comprising of an incoming circuit breaker and a number of small moulded case distribution circuit breakers.

The design and engineering process involved completing a detailed Power Studyto examine the consequences, in terms of fault rating, of adding the new equipment. Various scenarios were considered, and the financial impact was assessed to determine the most cost effective interconnection configuration. As a result of the study the amount of upgrade work required on the existing equipment was minimised.

The Power System Study was completed by gathering data about the existing switchboard arrangement and comparing this to the original, hand written, fault level calculations. The new calculations were performed using software modelling and verified to IEC 61363. The IEC 61363 Short Circuit study represents conditions that may affect typical marine or offshore installations more significantly than land-based systems, including more emphasis on generator and motor decay. This confirmed the original calculations were accurate.

As well as considering the effects of fault currents, Zeefax also completed a complete protective device co-ordination study to confirm and ensure that proper co-ordination was established for all operating scenarios. This included the existing equipment as well as the components in the switchboard extension, and the new 480 V switchboard and transformer.

Finally, the study also included calculating the strength and current-carrying capacity of the busbars under normal and fault conditions to establish the correct busbar sizes and bracing.

- Cellar jet constructed of 6" OD pipe with 2" NPT x 3/4" orifice jet nozzle nipple installed in 90° long radius ell. 6" line runs from cellar bottom

- Air Compressors for 535 CFM at 145 psi/1MPa each equipped with dual controls, including pipes valve fitting and two air receiver tanks of 600 gallons.

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- Cellar jet constructed of 6" OD pipe with 2" NPT x 3/4" orifice jet nozzle nipple installed in 90° long radius ell. 6" line runs from cellar bottom

- Air Compressors for 535 CFM at 145 psi/1MPa each equipped with dual controls, including pipes valve fitting and two air receiver tanks of 600 gallons.

The Montclair High School girls and boys swim teams pulled off a sweep on Monday night in the North 1 Group A state semifinals at Montclair State University.

The SCR Drive Assignment Contactors are fitted in the armature and are actuated by Allen Bradley PLC logic; through Allen Bradley flex I/O located in the SCR drive bay. The flex I/O communicates through a dual loop Profibus configuration to a processor for the first five SCR bays and a second matching configures for the next five SCR bays. The assignment configuration is such that any motor is assignable in three locations with any motor capable of assigning to the first five SCR bay or the second set of five SCR bays.

Each drive can support 4 different motor parameter sets. All the SCR Drives on the Frontier Driller shall be configured accordingly to the motors that they will support.

This architecture offers flexibility and reliability through redundancy in case of SCR drive failure. Should such an event occur the operator simply turns off the motor on the faulted SCR drive and turns back on allowing the PLC to assign to the next available SCR drive. Each motor is assignable to three different SCR drives with a total of twenty (20) SCR drives in the system.

The SCR Drives are controlled from consoles via profibus loop circuit to the dual redundant Logix 5561 CPU Allen Bradley PLC system. Overview of the SCR distribution with SCR PLC.

By use of the dual 5561 Allen Bradley processor (CPU) in the PLC system either processor can fail with no loss of operation. Communications to the drives is done by Profibus loop directly to the Siemens 6RA70 and flex I/0 locate each SCR bay. The flex I/O receives input and from devices outside the drive such as armature contactor feedback, drive cooling fan overload, circuit breaker status and the OFF/DRILL/MARINE selector switch. The flex I/0 receives output commands outside of the 6RA70 control for contactor assignments. The Siemens 6RA70 SCR drive sends and receives data as per the supplied manual, which controls operation of the motor and gathers operating information for logic control. All control signals from SCR to PLC shall be communicated through PROFIBUS DP field bus protocol, with the exception of the Emergency Stops, which shall be hardwired directly to the SCR Drive breaker for safety.

Signals exchanged between an SCR and its respective PLC are the same for each SCR. Apart from standard control/status signals, signals related to assignment and power management need to be exchanged.

This architecture offers flexibility and reliability through redundancy in case of PLC or communication failure. Should such an event occur, the communication cable could with stand one break in any loop and complete failure of either PLC1-A or PLC1-B with no loss of operation.

There is a PROFIBUS DP communication network for each SCR drive to the two PLC racks located in the generator cubicles. Each network is completely independent from the other with communications that are loop and able to be controlled by either CPU. The PLC racks located in the Driller’s Console and in the Mud Pump Console are networked by Ethernet Fiber optic loop to a MOXA module to convert the fiber signal. The two screens in the driller’s console are networked on this same loop with both screens able to display the same screens and status. There are two more MOXA modules connected in the same loop to supply data to the two workstations to enable data collection and trouble shooting of the complete system. There are two more MOXA modules on the same loop connected to PLC3A and PLC3B in the field supply cabinets, which in turn are connected to all the MCC, by Profibus fiber optic loop for control and status of all the required motor starters. Overview of the SCR PLC PROFIBUS DP and Ethernet communication network.

The PROFIBUS DP network in this application is based on 3 different mediums and topologies. A standard bus or line topology network with standard PROFIBUS DP RS-485 cable is established between an SCR PLC and its respective SCR drives. Each SCR is fitted with a CBP2 PROFIBUS communication board. Each one has its own address to differentiate between the various SCR Drives on the network. A redundant optical ring topology is established between all PLC racks via MOXA hub modules to form the Ethernet network. The third communication loop is Profibus fiber optic to all the Hirschmann Hub modules in the MCCs and the same type loop collecting data from the generator controls. MOXA modules and Hirschmann hub modules convert electrical signals to optical signals.

As of July 2007 we have completed the manufacturing portion of this project and have started testing the communications of the 5 remaining SCR Drive bays along with the Generator bays, Driller’s Console, Mud Pump Console & SCADA System. We have already shiped 5 DC drive bays and 1 of the 2 Isolation Switch bays and will ship the remaining equipment after completion of testing and DNV approvals.

REVISION HISTORYRev. A B C D E F G H J K Description Initial Release Added Revision History page and drawing number in footer. Revised figures 1-10, 113, and 1-14. Formatting corrections. Corrected text and figure item callouts items in figures 1-4, 1-5, and 1-6. Make formatting correction. Remove references to ARH and Ansaldo Ross Hill on pages 1-1, 1-2, and 1-25. Update figures. Update (2) photos (Figure 1-5, Figure 1-9); add photo numbers; update figure number style. Revise Figure 1-1 to reduce printing time and printer memory problems. Convert to Word 97 format. Add Table of Contents codes. Correct Level 5 and Level 6 styles and errors. ERO/ECN # 041251 C23375 C24068 C24394 C24670 C25368 C25939 C26330 C28670 C29222

SCR DRIVE SYSTEMSYSTEM INFORMATIONDESCRIPTIONThe SCR Drive System provides electrical power conversion and control for the DC motors on a drilling rig. The system regulates AC power from engine-generator sets and delivers continuously variable DC power to traction motors which are coupled to functions such as Drawworks, Rotary Table, Top Drive, Cement Pumps and Mud Pumps (see Figure 1-1). A typical drive system consists of the following units: Generator Units for control of enginegenerator sets. SCR Units for AC to DC rectification for traction motor power and control. Transformer Feeder Unit - AC feeder breakers to feed step-down transformers that deliver low voltage power for AC auxiliaries such as motor blowers, water pumping, lighting and living accommodations. DW Dynamic Brake - electrical resistance or regenerative brake for Drawworks motors. Field Supply Unit for DC field supply to shunt wound, separately excited DC traction motors. Driller"s Console for control of all drilling functions from the drill floor. Mud Pump/Cement Pump Console for local control of the pumps during maintenance. Motor Control Center containing starters for AC auxiliary motors and feeder breakers for lighting panels and smaller distribution transformers.

SPECIFICATIONSThe drive system conforms to IEEE-45 standards for electrical switchgear. For offshore systems, certification can be obtained from American Bureau of Shipping (ABS), United States Coast Guard (USCG), and Det Norske Veritas. See Table 1-1 for system specifications. Table 1-1. System Specifications ELECTRICALAC Input Prime Power Engine Governor Three phase, 60 Hz, 600 VAC Usable KW depends horsepower of prime mover. on

Generator Voltage Regulator 3% regulation one second response time with 10% load unbalance of rated KVAR"s DC Output Zero to 750 VDC at zero through maximum current

MECHANICALTemperature Range Cubicle Construction -22F to 105F (-30C to 40C) Fabricated from 12 gauge cold-rolled steel with welded construction and expanded metal ventilation openings. The cubicle bus is solid copper with a 0.0005 Inch (0.0013 cM) electroplating of silver. Fabricated from 12-gauge #304 stainless steel plate with welded construction.

FUNCTIONAL DESCRIPTIONFigure 1-2 shows a typical one-line diagram. Observe that power from the engine-generator sets is collected on a common AC bus. AC to DC rectification occurs in SCR bridges. The output of the SCR bridge is applied to the DC traction motors via contactors. Contactor logic is set at the Control Console being used. Note that circuit breakers isolate each generator set and SCR Unit from the Main AC Bus.

Adjust the VOLTAGE ADJUST control knob so the VOLTS meter indicates 600 Volts. Charge the circuit breaker (if necessary), by pushing the CHARGE pushbutton for electrically charged circuit breakers, or by cranking the circuit breaker handle for manually charged breakers. Close the circuit breaker by pushing the illuminated PUSH TO CLOSE pushbutton on the appropriate generator cubicle door. Turn the SYNC switch to the OFF position.

SYNCHRONIZING GENERATORSTO BRING AN ADDITIONAL GENERATOR ON LINE 1. (Models 1200, 1201, 1500) Turn the SYNCHRONIZING switch (Item 9 on Figure 1-3, Item 11 on Figure 1-4) to SYNC. (Model 1400) Turn the SYNCRONIZING switch (Item 15 on Figure 1-5) to the number of generator about to be brought on line. (Model 1600) turn the SYNCHRONIZING SWITCH (Item 20 on Figure 1-6) to AUTO. Position the VOLTS ADJUST knob (Item 13 on Figure 1-3 and 1-4, Item 10 on Figure 1-5, Item 17 on Figure 1-6) so the AC VOLTMETER (Item 5 on Figures 1-3 and 1-4, Item 18 on Figure 1-5, Item 7 on Figure 1-6) indicates 600 Volts.

STARTING AN ENGINE1. 2. 3. Place the ENGINE CONTROL switch to IDLE. Start the engine and run it at idle speed until it is warmed up. Place the ENGINE CONTROL switch to RUN. OR 1.

Figure 1-2. Typical One Line Diagram 3. Adjust the SPEED ADJUST knob (Item 12 on Figures 1-3 and 1-4, Item 9 on Figure 1-5, Item 18 on Figure 1-6) until the SYNCROSCOPE needle (Item 20 on Figures 1-3 and 1-4, Item 17 on Figure 1-5, Item 22 on Figure 1-6) moves clockwise (the engine/generator speed is faster than desired) and the two SYNCHRONIZING LIGHTS (Items 21 on Figure 1-3, Items 19 on Figures 1-4 and 1-5, Items 23 on Figure 1-6) brighten/dim.SCR DRIVE SYSTEM TECHNICAL MANUAL

Description GEN Circuit Breaker AC Kilowatts Meter AC Kilovars Meter AC Ammeter AC Voltmeter Generator Run Light Generator On Line Light Engine Control Switch Synchronizing Switch Ammeter Select Switch Voltmeter Select Switch Speed Adjust Knob Volts Adjust Knob % AC Ground Ammeter % DC Ground Ammeter Ground Fault Indicator Lamps Ground Detector Test Button Power Limit Light Hertz (Frequency) Meter Synchroscope Synchronizing Lights

Description GEN Circuit Breaker AC Kilowatts Meter AC Ammeter AC Kilovars Meter AC Voltmeter Generator Run Light Generator On Line Light Ammeter Select Switch Voltmeter Select Switch Engine Control Switch Synchronizing Switch Speed Adjust Knob Volts Adjust Knob % AC Ground Ammeter % DC Ground Ammeter Ground Fault Indicator Lights Ground Detector Test Push Button Power Limit Light Synchronizing Lights Synchroscope Hertz (Frequency) Meter

Description GEN Circuit Breaker AC Kilowatts Meter Kilovars Meter AC Ammeter Engine Control Run/Off/Idle Switch GEN Run Light GEN On Line Light Push to Close Lighted Pushbutton Speed Adjust Knob Volts Adjust Knob % AC Ground Fault % DC Ground Fault Ground Fault Indicator Lights Ground Detector Test Push Button Generator Synchronization Select Switch Frequency (Hertz) Meter Synchroscope AC Voltmeter Synchronizing Lights Power Limit Light Hour Meter

Description AC Kilowatt Meter Temperature Meter Kilovars Meter AC Ammeter % DC Ground Meter % AC Ground Meter AC Voltmeter Generator Run Light Circuit Breaker Push to Charge Push Button Ground Fault Indicator Lights Ground Detector Test Push Button Circuit Breaker Indicator Lights

Description Ammeter Select Switch Engine Governor Switch Circuit Breaker Switch Voltmeter Select Switch Volts Adjust Knob Speed Adjust Knob Temperature Select Switch Synchronizing Switch Frequency (Hertz) Meter Synchroscope Synchronizing Lights GEN Circuit Breaker

1-9 4. Crank the handle of the GEN CIRCUIT BREAKER (Item 1 on Figures 1-3, 1-4, and 1-5, Item 24 on Figure 1-6) once to charge the GEN CIRCUIT BREAKER. Close the GEN CIRCUIT BREAKER when the needle of the SYNCROSCOPE points straight up, the SYNCHRONIZING LIGHTS go out, and the PUSH TO CLOSE pushbutton on the GEN CIRCUIT BREAKER is illuminated. Position the VOLTAGE ADJUST knob so the KVAR meter gives the same reading as the other generator(s) on line. Turn the SYNCHRONIZING SWITCH to the OFF position. 2. Charge the circuit breaker (if necessary), by pushing the CHARGE pushbutton (for electrically-charged circuit breakers) (refer to Figures 1-3 through 1-6) or by cranking the circuit breaker handle (for manually-charged circuit breakers). Some systems have molded-case circuit breakers. These do not require charging. Close the SCR circuit breaker by pushing the PUSH TO CLOSE pushbutton (this may be mounted remotely or directly on the circuit breaker). Crank the circuit breaker handle once to close molded-case circuit breakers.

REMOVE GENERATOR FROM LINE AND STOP ENGINE1. 2. 3. Open the circuit breaker by pushing the circuit breaker OFF pushbutton. Place the ENGINE CONTROL switch in the IDLE position. If the GOVERNOR CONTROL switch has an OFF position, go to the OFF position only after engine has cooled down. If system equipped with a GOVERNOR CONTROL pushbutton switch, the engine must be shut down at the engine.

SWITCH ON AUXILIARIES1. Close the feeder circuit breaker to feed AC supply to the distribution transformers and the MCC. Close the circuit breakers corresponding to each of the blowers and auxiliaries. Set the HAND/OFF/AUTO switch to AUTO (if applicable). If the motors are shunt wound, switch on the appropriate field power supplies. Each motor"s field current should be 50 Amps (or per the motor nameplate rating).

1-10 KW SHARING (CONCLUDED) The master generator is the lowestnumbered unit connected to the Main AC Bus. The remaining generators are slaved to the master. For example, if Generator 1, 2, and 4 are connected to the Main AC Bus, Generator 1 is the master. In systems using Auto Share (Auto Sync) AC Control Modules, master/slave floats. No AC Control Module can be the dedicated master in an Auto Share system. The magnetic coupling that exists between paralleled generators insures that all engine generator sets connected to the Main AC Bus at the same time will run at the same speed. The SPEED ADJUST knob on the master generator has total control of the Main AC Bus frequency. The slave units SPEED ADJUST controls are disabled. The combination of KW (Real Power) and KVAR (Reactive Power) sharing between engine generator sets should cause all generator AMMETERS to read about the same value. Any imbalance in the readings of the various KVAR meters can be adjusted by using the VOLTAGE ADJUST knob of the generator that has the lowest KVAR meter reading. POWER DISTRIBUTION Distribution of the total power is governed by the following equation: DCPower Demand = Power Used (Total - AC) Bring additional generators on line to increase the total power available. To increase the total DC power available, increase the total power by putting more generators on line. AC power is usually a small fraction of the DC power. To increase power for a specific DC function, it also helps to reduce the power consumed by the other DC functions.SCR DRIVE SYSTEM20605-45 Rev K

Due to the Main AC Bus feature and the Power Limit circuit, it is possible to connect as few generators to the Main AC Bus as are necessary to do the work. For economy and efficiency, match the total available power to the total load.

CRISIS OPERATIONUNIT MALFUNCTION The GEN ON LINE and SCR ON lights will illuminate when the respective units are connected to the Main AC Bus. The lights go out when that unit is tripped off-line (disconnected from the Main AC Bus). If a generator\SCR unit becomes inoperative, continue the system operation on other units. SYNC MALFUNCTION If the SYNCHROSCOPE is inoperative, use the SYNC lights to parallel the generators. If both the SYNCHROSCOPE and the SYNC lights fail, use a Multimeter. Switch the Multimeter to a 600 VAC scale. Connect it across the generator circuit breaker from the top to the bottom of any one phase. The voltage will swing from minimum to 600 VAC just as the SYNC lights should change from dim to bright. Adjust the SPEED ADJUST knob for the oncoming generator until the swing slows. Close the circuit breaker when the Multimeter voltage reading is minimum. TRANSIENT AC SURGE The green SURGE SUPPRESSION light will extinguish if a problem blows the Surge Suppression Circuit incoming line fuses.

1-11 SPROCKET SLIP The SPROCKET SLIP light illuminates when Mud Pump assignment contactors trip. This is caused by a sprocket slip, chain failure, or belt slippage on a dual motor mud pump. After the chain drive is repaired, push the SPROCKET SLIP RESET button to extinguish the SPROCKET SLIP light and to allow the contactors to close. GROUND FAULT The three GROUND DETECTOR lights and the % AC GROUND and % DC GROUND meters indicate ground faults. These are only indicators and the fault must be located and corrected. AC ground faults can occur anywhere along the AC power network (generator to AC bus cables, feeder distribution to the AC motors, and the generator control bus in the cubicle itself). The GROUND DETECTOR lights will isolate the fault to one of the phases, and the % AC GROUND meter will indicate the degree of the fault. DC ground faults may occur anywhere along the DC network from the DC (+) and DC (-) buses in the SCR cubicles to the motor cables. Isolate the fault to one motor by observing the % DC GROUND meter. The % DC GROUND meter needle will fluctuate as the faulty motor speed is changed.

SHUT DOWN INSTRUCTIONS1. Turn off the SCR unit by tripping the SCR circuit breaker. The SCR ON light will extinguish. Disconnect the generator from the Main AC Bus by tripping the Generator circuit breaker. The GEN ON LINE light will extinguish. Push the engine IDLE pushbutton. Cool the engine per the engine manufacturer. After the engine cool-down period is over, turn the Generator Control cubicle OFF/IDLE/RUN switch to OFF to stop the engine. Shut down the fuel rack if there is no OFF button.

CAPABILITIESFigure 1-7 shows an SCR bridge Current versus Voltage response curve. Figure 1-8 shows DC series and shunt motors Speed versus Torque curves. These are for a specific brand and model motor. Other brands and models will be different.

MAINTENANCEThis chapter contains information to assure proper operation of the system through periodic functional tests and preventive maintenance. If the system fails to perform as indicated in the functional test instructions, consult the troubleshooting guidelines listed in this manual.

If the house is not ordered, the equipment should be handled with care to prevent excessive mechanical shock, and protected from possible damage due to moisture and dirt during rig-up. See Figures 1-11 and 1-12 for cubicle lifting procedure.

RECEIVING & HANDLINGSCR switchgear is normally installed in a truckload-sized house (see Figure 1-9), a self-contained, structural steel building mounted on skids. Cabling to external devices such as generators, motors and control consoles is terminated at weatherproof plug panels (see Figure 1-10).

If an SCR house was not ordered, refer to the following instructions for installation of the SCR Cubicles. Figure 1-14 shows a typical SCR Drive Cubicle lineup.

CUBICLESPRELIMINARY CONSIDERATIONS Door Clearance The SCR room must be large enough to allow the doors to be opened 90 degrees. The doors cover the full height of the cubicles. The height of the room must have clearance for the cable tray, piping, and ducting. Ventilation and Ducting The room air must be changed twice per minute when the cubicles are enclosed in a room. Ducting in the front and rear of the room should force the air to flow the full length of room. Heat Loss Heat loss for a SCR system housed in a room fully insulated on walls, floor and ceiling, and containing no distribution transformers, is approximately 2.5 tons for each 1,000 HP of DC load. Vibration Pads If the cubicles are mounted in a high vibration area, such as the region close to the engine skid, the cubicles should be mounted on vibration insulating pads. The vibration frequency should be within 30 Hz, and the amplitude should not exceed 0.02 cM. Korfund spring-type vibration isolators are recommended. Location Lift the cubicle with a crane into the general installation area. Use four lifting points per cubicle. Refer to Figures 1-11 and 1-12 for the lifting procedure.

Use hydraulic hand trolleys (Rol-A-Lift or equivalent) to move the cubicles into the exact location. Two trolleys may be required for wide cubicles such as the Motor Control Center. Cover the vertical rest beams of the trolleys with carpeting to protect the finish of the cubicle panels. Slide the trolley horizontal forks all the way underneath the cubicle. Jack up the cubicle approximately 6" (15 cm) above the floor. Push the cubicle carefully into the location, jack down, and remove the trolley horizontal forks. Mounting Butt the sides of the cubicles tightly together. Bolt the cubicles together at the top and bottom using 3/8" bolts. Install the AC bus splices to connect the bus together from cubicle to cubicle. Cable Installation Refer to the cabling diagrams in the SCR job book. Cables between the cubicles are furnished by the customer unless the SCR drive system is installed in a Power Control Building. All power terminations are made through the cubicle top unless otherwise designed. If the SCR system is supplied inside a Power Control Building, power and control cable terminations are at one end of the building. The terminations are copper stubs with an one inch diameter bolt hole. The customer should furnish plated-copper, crimp-type lugs. Avoid screw-type pressure connectors.SCR DRIVE SYSTEM TECHNICAL MANUAL

1-19 If multiple single conductor cables are used to feed the system, transposing of the cables must be considered to ensure current sharing between conductors. Control Consoles The Driller"s Console is typically mounted on top of the Drawworks pneumatic control console. The Mud Pump and Cement Pump consoles are provided with tabs. Each tab has a bolt hole for wall installation. Refer to the respective console drawings for detailed installation instructions. Control cable terminations are made from the bottom with plug-in-type Pyle National connectors or screw-type terminal blocks fed through stuffing tubes. Team Work Maintenance work should preferably be performed by a team of two electricians. This assures help in an emergency situation. Personal Wear Do not wear metallic watch straps, rings, or bracelets. Live Circuit Consider all circuits to be energized unless known to be dead. Tools All electric tools should be grounded. Handles on the tools should be insulated. Do not leave tools in the cubicles after the work is completed. Fuses Close a fuse by pushing on the plastic cover. Do not place a finger underneath the cover. Fire Remove power to the unit under fire. Read the label on the fire extinguisher to be sure it can put out an electrical fire. Water may be used, but be very certain that all power is removed including the power on the main bus.

TESTINGThis section contains information to test the proper functioning of the SCR Drive System. Perform the test daily. If the system fails any part of the test, use the Troubleshooting section to locate the malfunction. SAFETY PRECAUTIONS IF CARELESSLY HANDLED, THE SCR DRIVE SYSTEM CAN INFLICT GRAVE INJURY. SAFETY PRECAUTIONS MUST BE OBSERVED AT ALL TIMES TO PREVENT ELECTRIC SHOCK.

1-20 DAILY TEST Perform the following checks to assure the proper functioning of the drive system. 1. 2. Check lights and meters on cubicles and control consoles. Check Ground Detector indicators. All three lamps should glow a dim orange. The Ground Fault Percentage meters should read close to Zero. Check field current supply of all shunt motors. Ensure that KW"s and KVAR"s are shared between all the generators on line. During tripping, listen for switching action of the DW Dynamic Brake contactor. Ensure that all SCR blowers are running. System more reliable and last longer. A reliable system is less likely to suffer sudden failures or deteriorate below the performance specifications. The system components are vulnerable to three factors: inferior quality, harsh operation and severe environment.

QUALITYEfforts to eliminate this source of failure are made at our manufacturing and testing facility. The system is rigorously tested through every phase of operation. The electronic modules are placed in ovens at 165F (75C) for 96 hours to simulate numerous hours of operation at normal temperature. Thus, components which are likely to fail during the first hours of operation are replaced before shipment.

HARSH OPERATIONThe drive system should be operated within its capabilities. Operation above the ratings subjects the system to severe strains. The controls should be handled with care. A harsh switching action can generate a damaging transient overload.

MONTHLY TEST Perform the "Mechanical Overspeed Trip" and "Reverse Power Trip" Functional tests, located in Table 2-4 (see Section 2). 1. Check waveshape of SCR Amps at the test pins on the DC Control Module. See the SCR Unit section for further details. Inspect the cooling inlet filters and clean/replace as necessary.

ENVIRONMENTHEAT Components can fail suddenly due to overheating. Even though the drive system is rated between -22F (-30C) through 104F (40C), the system operation is more reliable at normal temperatures. Components age faster at temperature extremes. The blowers in each SCR cubicle remove the heat from the electrical assemblies. As a further precaution, vital units such as the SCR bridges and electronic modules have heat sinks for faster cooling. Inspect theSCR DRIVE SYSTEM TECHNICAL MANUAL

SERVICINGServicing consists of cleaning the system components and replacing those which have become defective or worn out. Periodic servicing will make the SCR DriveSCR DRIVE SYSTEM20605-45 Rev K

1-21 assemblies frequently for indications of overheating such as charring or burned insulation due to loose connections. Replace the damaged components even thought they may not have failed completely. VIBRATION The drive system units do not generate vibrations. However, vibrations from rotating machinery such as the generator set cause mechanical stress which can loosen connections and crack insulation. DUST Dust is attracted to high voltage switchgear surfaces because of the static electricity charge. As a result, circuit discontinuities, or even shorts can occur. MOISTURE Moisture aggravates problems caused by dust. The contaminants cake on the components and conductivity is increased. Further, corrosion can occur. Servicing consists of three operations: cleaning, inspection, and replacement. CLEANING 1. Wipe clean the cubicle and component surfaces with a lint-free cloth moistened with a mild cleaning solvent. Be sure to leave the surfaces dry. TURN OFF THE MAIN POWER TO THE SYSTEM BEFORE CLEANING. TEST THE CLEANING SOLVENT ON A SMALL SURFACE TO MAKE SURE IT DOES NOT DAMAGE THE PLASTIC PARTS OR INSULATION, OR REMOVE PAINT. 2. Clean all cubicle and air conditioning filters. Check Driller"s console and Foot Throttle for air pressure. If there is moisture inside the compartments, the dryer in the air line may be clogged. Check assignment contactors. Inspect the coils for signs of overheating such as discoloration or charred insulation. Check contacts for corrosion or pitting. Inspect the freewheeling diodes; also inspect auctioneering diodes in the system. INSPECTION Check all components for overheating and corrosion. Replace damaged components even if not completely failed. Inspect cables and wires for broken or burned insulation. Tighten all connections and check switches, knobs, and buttons for easy movement. CARELESS INSPECTION ITSELF CAN CAUSE MALFUNCTIONS. DO NOT TUG CABLES AND WIRE HARNESSES, SHAKE THE ELECTRONIC ASSEMBLIES OR FIDDLE WITH THE KNOBS. EMPLOY VISUAL INSPECTION AS FAR AS POSSIBLE. Operating conditions dictate the servicing period. Adhere to the following schedule during the initial period and adjust it according to need. CONNECTIONS Experience has shown that many problems with electrical equipment are the result of loose connections. Periodic checks for tightness can be helpful. WEEKLY SERVICING

1-22 ENVIRONMENT (CONCLUDED) 4. Clean tachometer pickup plugs. Do not screw pick up in too far. Flywheel will damage coil upon starting diesel. Check AC leakage for every SCR bridge. 5. 6. Open and inspect all generator and traction motor covers. Open all fuses in the system and high-resistance check the main three phase bus bars before applying power. Remove covers and inspect SCR bridges. Clean as necessary. Reconnect HOC batteries. If good, they will fully recharge within 24 hours. Clean all potentiometer windings (speed adjust, voltage adjust, hand throttles, foot throttle). Tighten all bus bar bolts and screw connections. Manually phase-up each SCR bridge as soon as possible. Inspect all power resisters for cracks. Check AC leakage on all SCR bridges. Check knob settings on EGB-10P or 13P actuators. Check resistance of all magnetic pickup circuits and all actuator circuits. Check compatibility of all modules. Check outputs of hand and foot throttles. Check current and voltage feedback for all SCR bridges. Perform emergency-off and reverse power trip tests for all engines. Verify sync circuits with a VOM. If equipment has been idle for more than one year, all electrolytic capacitors should be replaced.

STORING AN SCR DRIVE SYSTEM1. 2. Disconnect HOC batteries at the battery terminals. It is important to keep the SCR house interior dry while stacked. Install covers on all external connectors on the plug panels. Place corrosion inhibitors in consoles and cabinets. Seal any openings to keep varmints out. Lift the brushes on traction motors. Apply power to generator and traction motor heaters if possible. Heaters in electrical equipment areas are helpful. Cover traction motor blower openings.

REMOVING AN SCR DRIVE FROM STORAGE AND PLACING IT IN SERVICE 1. Inspect bus bars for debris. Inspect and clean throughout cubicles, consoles, MCC cans and underneath the main and switchgear line-ups. Physically rotate the SCR blowers. Manually operate all motor starters and contactors before powering up. Open and inspect all modules.

TROUBLESHOOTINGOVERVIEWTroubleshooting allows the isolation of a malfunctioning SCR Drive System unit. It consists of first looking at the broad possibilities of failure, and then breaking down the likely possibility into successively smaller trouble spots. Examine the whole system as it is situated between the generators and the loads. Then narrow the search to a cubicle or console, then to an internal assembly, and finally to a component. The malfunction can be quickly located by seeking out signs of trouble, such as extreme readings on the meters, tripped circuit breakers, and smoking components. A step-by-step troubleshooting approach should consist of the following items: malfunction analysis, analysis of front panel indicators, systems analysis, and signal tracing.

ANALYSIS OF FRONT PANEL INDICATORSMany malfunctions can be located by analyzing the meters and lights on the front panel. Warning lights on the cubicle panels flag ground faults, AC surge, sprocket slip, and reverse power conditions. Operational lights indicate whether a SCR or a Generator is on the bus. Even voltmeters and ammeters provide valuable troubleshooting information. For example, a stalled motor is indicated by high current, and low voltage. Low current and high voltage is an indication of an unloaded motor.

SYSTEMS ANALYSISThink of the system as being made up of interrelated blocks or units. Ignore the contents of the unit, and simply consider the inputs and outputs. Refer to Figure 115.DRILLER"S CONSOLE GENERATOR

MALFUNCTION ANALYSISTroubleshooting is easier and faster if the nature of the malfunction is pinned down. Sometimes, the faulty behavior of the system may be caused by operator error. For example, the Driller may forget to turn on the lockout switch, open the throttle, and assume that the SCR unit is defective. The faulty behavior of a motor or generator may be blamed on the SCR system. Make sure the fault is not outside the system before making extensive repairs such as replacing a SCR cell. If the malfunction occurs off and on, it may be useful to keep a log of the system parameters with a strip chart recorder.SCR DRIVE SYSTEM TECHNICAL MANUAL SCR DRIVE SYSTEMDC ELECTRONIC MODULE CIRCUIT BREAKER

1-24 SYSTEMS ANALYSIS (CONCLUDED) A malfunctioning unit does not provide the correct outputs. The fault may be due to incorrect inputs. If not, some of the assemblies within the unit may be defective. To troubleshoot, the system, first isolate the faulty unit by examining the outputs of the suspected units. Then examine the inputs to the faulty unit. If one of the inputs is incorrect, trace the signal from the incorrect input to its source unit. If, however, the inputs are correct and the outputs are incorrect, troubleshoot the defective unit. Isolate the fault to any one of the unit assemblies by a similar system analysis. Inputs to many of the SCR Drive System units are of two forms: power and control. For example, a SCR cell must receive the AC supply and the control firing pulse at the gate. If both the inputs to the SCR cell are correct and the output of the SCR cell is incorrect, the cell is defective. The defective unit can be easily located by tracing signals associated with the malfunction. The motor can be operated on any one of the two power lines (refer to Figure 1-16). If it fails to run, the fault can be in the motor, the assignment switch, or the power lines. The power line can be checked out by simply switching the motor to one of the other lines. If the motor runs, then obviously, the first power line is defective. Each power line is made up of components in series. If the power line circuit is defective, all the components and the wiring must be suspected. The defective component can be located by tracing the power supply from the motor back to the generator. Begin the signal tracing at the motor. If power is present at the motor and the motor is not running, the motor is defective. If power is absent at the motor, check for its presence on both sides of the contactor. If power exists on the SCR side, but not on the motor side, the contactor is open. Signal tracing should continue back toward the Generator until the defective component is located. In extremely long series circuits, it may be convenient to divide the circuit in half. Begin the probe in the middle. If the signal is missing, trace back toward the generator until the signal is regained. If the signal is present, trace away from the generator until the signal is lost.

SPECIAL TOOLS AND EQUIPMENTThe following instruments are needed to troubleshoot the SCR Drive System. MULTIMETER The Simpson Model 250 (or equivalent) is recommended to measure voltage and resistance values. The meter should be insulated, rugged and possess:DC/AC Volts:Zero through 1,000 Volts in several ranges. Accuracy: 3% of full scale. Ohms: Zero through 10 M in several ranges. Accuracy: 2% of arc length.

AC/DC CLAMP-ON AMMETER This meter is used to safely measure high currents. The Columbia Model 1000A is recommended. OSCILLOSCOPE The oscilloscope is used to check the SCR gate pulses and ripple on various DC voltages. The Tektronix Model 305 (or equivalent) is recommended. The unit chosen should have >3 Inch diagonal viewing screen and two channels for comparing two signals.

It is recommended that digitaltype meters not be used for measurements in power circuits. It has been found that, in some cases, reading inaccuracies may be induced by digitaltype meter usage. Digital multimeters may be used to measure voltage and current signals in the SCR drive but you should be aware that some digital meters are overly sensitive to the high electrical noise typical of that found in any switching high power supply. Digital meters that are not designed with proper filtering and measuring techniques and can give inaccurate readings.

REMOVAL & REPAIRCUBICLE REMOVALIf a cubicle is damaged beyond repair, perform the following steps: 1. Disconnect power cables from the bus stubs located at the top of the cubicle. Remove bus links which connect the AC bus from cubicle to cubicle. Remove the bolts which join the cubicles at the top and bottom. Slide the fork of a hydraulic hand trolley underneath the cubicle and jack it up approximately 6" above the floor. Pull out the cubicle carefully, taking care not to bump the adjoining cubicles.

CUBICLE REPAIRRepair of the SCR Drive System normally consists of repairing an assembly within a system unit. A system unit is not replaced unless it is damaged beyond repair. When a unit is replaced, perform a functional test on it before operating the system. Refer to the respective unit manual for test instructions.2. Release the wiring harness by removing each wire from the terminal board.FS-047-05

AC CONTROL MODULEIf an AC Control Module is malfunctioning, replace it with the spare AC Control Module and return the faulty unit to us. To remove and replace the AC Control Module perform the following steps.FS-066-03

Reconnect the wiring harness by replacing each wire on the terminal board. Ensure that each wire is correctly placed and that the retaining screw is tightened.