1988/11/28 Caterpillar

Potentiometer Can Be Used In Place Of Temperature Probe For Demonstration Of Electronic Modular Control Panel {0315,7418}

Usage:

All Package Generator Sets With 7C1000 or 9Y1400 Electronic Modular Control Panels (EMCP)

Reference: Electronic Modular Control Panel (7C1000) Service Manual Module SENR3535, Page 52, and Electronic Modular Control Panel (9Y1400) SENR3903, Page 47, for use in Service Manual SENR7958 on power generator sets.

The above Service Manual modules list resistance values of the temperature probe in the EMCP at room temperatures. Some dealers have requested resistance values at various engine operating temperatures, which are much higher than those listed in the Service Manuals. This would make it possible to replace the temperature probe with a resistor, and actually demonstrate the correct function of the EMCP.

The 7C4471 Potentiometer can be used for this purpose. It is a 10,000 ohm multiple-turn potentiometer normally used with the VR3 voltage regulator. The resistance values in ohms for selected operating temperatures are in the following list. With the potentiometer adjusted to these values, the EMCP should indicate the corresponding temperatures. Write this data on the referenced pages in the Service Manuals.

30°C (86°F) 8057 ohms

60°C (140°F) 2488 ohms

90°C (194°F) 915 ohms

98°C (208°F) 719 ohms

107°C (225°F) 555 ohms

125°C (257°F) 342 ohms

Caterpillar Information System:

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1988/11/21 Fuel Priming Pump Available As An Attachment{1258}

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1988/11/21 Rechargeable Portable Printer Available{0782,1050,1250}

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1988/11/21 Fabric Seat And Back Cushions Available For Parts Service{7307,7312}

1988/11/14 New Liner Seat Insert Available{1201,1216,1217}

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1988/11/28 Bleed Holes Now In Paddle In Air Inlet Shutoff Groups {1078}

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1988/12/12 Oil Cooler Bypass Elbow Changed To Prevent Bypass Valve Seizure{1314,1318}

1988/12/12 Valve Kit Available For Explosion Relief Valve{1201,1233}

1988/12/19 New Material Used For Rotating Seal Rings In Some Power Shift Transmissions, Steering Clutches And Torque Converters {3101,3150,4100}

1988/12/19 New Camshafts Used; Camshaft Installation Kits Available {1209,1210}

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