Carrier XRV, 19XR Dry Run to Test Start-Up Sequence, Check Motor Rotation, Correct Motor Rotation

Dry Run to Test Start-Up Sequence

For electro-mechanical starters.

1.Disengage the main motor disconnect (CB1) on the start- er front panel. This should only disconnect the motor power. Power to the controls, oil pump, and starter con- trol circuit should still be energized.

2.Observe the default screen on the CVC/ICVC: the status message in the upper left-hand corner reads, “Manually Stopped,” Press the CCN or LOCAL softkey to start. If the chiller controls do not go into a start mode (“Unoc- cupied Mode” is displayed) go to the SCHEDULE screen and override the schedule or change the occupied time. Press the LOCAL softkey to begin the start-up sequences.

3.View the STARTUP display screen and verify the chilled water and condenser water pumps have energized.

4.Verify the oil pump has started and is pressurizing the lubrication system. After the oil pump has run about 11 seconds, the starter energizes (COMPRESSOR START CONTACT is closed) and goes through its start-up sequence.

5.Check the main contactor (1M) for proper operation.

6.The PIC II eventually shows an alarm for motors amps not sensed. Reset this alarm and continue with the initial start-up.

For Benshaw Inc. solid-state starters:

1.Close the main motor disconnect (CB1). Voltage will be applied to the compressor motor but the SCRs will not fire (compressor motor will not rotate). Enter MENU 4 in the Benshaw RediStart MICRO™ Menu structure at the Benshaw display (see Input Service Configurations, Change The Benshaw RediStart MICRO Software Con- figuration page 57). Select Dry Run Mode and scroll to YES.

2.Follow steps 2 through 4 for the electro-mechanical start- ers. When the Ramp Time is set for less than 10 seconds COMPRESSOR RUN CONTACT will close.

3.The PIC II eventually shows an alarm for motors amps not sensed. Reset this alarm and enter MENU 4 in the Benshaw display. Select Dry Run Mode and scroll to NO. Continue with the initial start-up.

Check Motor Rotation

1.Engage the oil pump circuit breaker (CB3) located inside the right hand side of the starter panel.

2.Then engage the control power circuit breaker (CB2) lo- cated in the same section of the starter cabinet.

3.Finally close the main motor disconnect (CB1) on the front of the starter panel.

4.The ISM mounted in the electro-mechanical starters checks for proper phase rotation as soon as power is applied to the starter and the PIC II controls power up. Solid-state starters have phase protection and do not per- mit a start if the phase rotation is not correct.

5.An alarm message will appear on the CVC/ICVC if the phase rotation is incorrect. If this occurs reverse any 2 of the 3 incoming power leads to the starter and reapply power. The motor is now ready for a rotation check.

6.After the default screen status message states ‘Ready to Start’ press the LOCAL softkey. The PIC II control per- forms start-up checks.

7.When the starter is energized and the motor begins to turn, check for clockwise motor rotation (Fig. 33).

Fig. 33 — Correct Motor Rotation

Do not check motor rotation during coastdown. Rotation may have reversed during equalization of vessel pressures.

Check Oil Pressure and Compressor Stop

1.When the motor is at full speed, note the differential oil pressure reading on the CVC/ICVC default screen. It should be between 18 and 30 psid (124 to 206 kPad).

2.Press the Stop button and listen for any unusual sounds from the compressor as it coasts to a stop.

To Prevent Accidental Start-Up — A chiller STOP override setting may be entered to prevent accidental start-up during service or whenever necessary. Access the MAINSTAT

screen and using the NEXT or PREVIOUS softkeys, high- light the CHILLER START/STOP parameter. Override the cur-

rent START value by pressing the SELECT softkey. Press the STOP softkey followed by the ENTER softkey. The word SUPVSR! displays on the CVC/ICVC indicating the override is in place.

To restart the chiller the STOP override setting must be re- moved. Access the MAINSTAT screen and using NEXT or PREVIOUS softkeys highlight CHILLER START/STOP. The

3 softkeys that appear represent 3 choices:

•START — forces the chiller ON

•STOP — forces the chiller OFF

•RELEASE — puts the chiller under remote or schedule control.

To return the chiller to normal control, press the

RELEASE softkey followed by the ENTER softkey. For more information, see Local Start-Up, page 46.

The default CVC/ICVC screen message line indicates which command is in effect.

Check Chiller Operating Condition — Check to be sure that chiller temperatures, pressures, water flows, and oil and refrigerant levels indicate the system is functioning properly.

Instruct the Customer Operator — Ensure the op- erator(s) understand all operating and maintenance procedures. Point out the various chiller parts and explain their function as part of the complete system.

COOLER-CONDENSER — Float chamber, relief valves, re- frigerant charging valve, temperature sensor locations, pressure transducer locations, Schrader fittings, waterboxes and tubes, and vents and drains.

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