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Carrier 19XL User Manual

Page 138

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2. On low-voltage compressors (600 v or less) connect voltmeter across the power wires to

the compressor starter and measure the voltage. Compare this reading with the voltage

rating on the compressor and starter nameplates.

3. Compare the ampere rating on the starter nameplate with the compressor nameplate. The

overload trip amps must be 108% to 120% of the rated load amps.

4. The starter for a centrifugal compressor motor must contain the components and terminals

required for PIC refrigeration control. Check certified drawings.

5. Check the voltage to the following components and compare to the nameplate values: oil

pump contact, pumpout compressor starter, and power panel.

6. Be sure that fused disconnects or circuit breakers have been supplied for the oil pump,

power panel, and pumpout unit.

7. Check that all electrical equipment and controls are properly grounded in accordance with

job drawings, certified drawings, and all applicable electrical codes.

8. Make sure that the customer’s contractor has verified proper operation of the pumps,

cooling tower fans, and associated auxiliary equipment. This includes ensuring that motors

are properly lubricated and have proper electrical supply and proper rotation.

9. For field-installed starters only, test the machine compressor motor and its power lead

insulation resistance with a 500-v insulation tester such as a megohmmeter. (Use a 5000-v

tester for motors rated over 600 v.) Factory-mounted starters do not require a megohm test.