Section III. CONTROL CUBICLE

TM 5-6115-545-34 (8) Repeat paragraphs (5), (6), and (7) above for other c. Installation. Refer to Operator and Organizational lights, connecting pin C to pins F, G, H, I, K, L, M, and N. Maintenance Manual and install the fault indicator. Section III. CONTROL CUBICLE 3-5. Removal, Disassembly and Repair. WARNING To avoid serious injury to personnel before do- ing any work in the control cubicle, be sure all power circuits are disconnected. Never work in the control cubicle while the engine is running. Killing voltages are present. a. Removal. Refer to Operator and Organi- zational Maintenance Manual and remove the control cubicle. b. Disassembly. Refer to Operator and Organizational Maintenance Manual and disassemble the control cubicle, See figure 3-3 and disassemble the relay assembly. (1) Clean all components with low pressure compressed air, or wipe clean with dry, lint free cloth. (2) Inspect for broken fuseholders, cracked or broken lamp holders, damaged meters, broken terminals on com- ponents, damaged wire insulation, broken wires and bent or broken connector pins. (3) Replace any components which show visual damage, such as cracked or broken meters, broken lamp holders, or cracked or broken switches and rheostats. (4) Inspect control panel relay assembly for damage. Replace component (fig. 3-3) if damage is evident. If any connections are opened or bared for test purposes, or if any defective components are replaced, the effected areas and components must be coated with polyurethane resin to pre- vent oxidation or other corrosion. The coating must be a minimum of 0.007 inches and air bubble entry into the ap- plied polyurethane must be controlled so that the legibility of component coding and identification is not impaired. The polyurethane resin to be utilized will correspond to MIL- I-46058 grade S, Type PUR. 3-6. AC Wattmeter Convertor Testing. To test the ac wattmeter of the control cubicle proceed as follows: b. Start the generator set. — c. Vary load and compare the readings of the ac watt- meter on the set with readings of the master wattmeter. d. The operating set wattmeter error must not exceed 10 percent of full scale value. If it does, replace the ac watt- meter. If it does not, proceed to para 3-7. 3-7. Transducer Testing. To test the control cubicle watt transducer, proceed as follows; a. Connect the watt transducer to the test equipment as illustrated in figure 3-4. Use a calibrated % of rating meter. b. Adjust all autotransformers T1, T2 and T3 to their MIN positions. c. Close switch S1 and open switches S2 and S3. d. Energize the power source. — e. Adjust T1 until 600 milliamperes is indicated on am- meter A1. The % of rating meter of known accuracy should indicate approximately 33%. f. Close switch S2 and adjust T2 until 600 milliamperes is indicated on ammeter A2. The % of rating meter should indicate approximately 66%. g. Close switch S3 and adjust T3 until 600 milliamperes is indicated on ammeter A3. The % of rating meter of known accuracy should indicate 100%. h. Replace the thermal watt transducer if it does not — satisfy the above requirements. i. If the transducer meets the above requirements, replace the wattmeter. 3-8. AC Ammeter Testing. To test the ac ammeter of the control cubicle, proceed as follows: a. Connect a suitable master ac current meter in series — with the set ac current meter. b. Start the unit and connect a variable load to the output — terminals and compare the readings of the two meters. c. The generator set ac ammeter error must not be greater than 2 percent of full scale value. If it is, replace the ac ammeter. a. Connect a master 3-phase wattmeter of known accuracy (1/2 of 1 percent) and a suitable variable load to the output of terminal lugs of the generator set. 3-4 Change 8