Carrier HFC-134A Relief Valve Locations, Close the door to the control center

Table 11 — Relief Valve Locations

LOCATION	FRAME	RELIEF VALVE OUTLET SIZE	QUANTITY WITHOUT	QUANTITY WITH
	SIZE		ISOLATION VALVES	ISOLATION VALVES
Discharge Pipe Assembly	3-5	11/4-in. NPT FEMALE CONNECTOR	0	1
Cooler	3-5	11/4-in. NPT FEMALE CONNECTOR	2	1
Condenser	3-5	11/4-in. NPT FEMALE CONNECTOR	2	2
Optional Storage Tank	N/A	1-in. NPT FEMALE CONNECTOR	2	2

NOTE: All valves relieve at 185 psi (1275 kPa).

DC bus capacitors in the VFD retain hazardous voltages after input power has been disconnected. After disconnect- ing input power, wait 5 minutes for the DC bus capacitors to discharge then check both the VFD DPI Communica- tions Interface Board Status LEDs and the VFD with a voltmeter to ensure the DC bus capacitors are discharged before touching any internal components. Failure to observe this precaution could result in severe bodily injury or loss of life.

The drive can operate at and maintain zero speed. The user is responsible for assuring safe conditions for operating personnel by providing suitable guards, audible or visual alarms, or other devices to indicate that the drive is operat- ing or may operate at or near zero speed. Failure to observe this precaution could result in severe bodily injury or loss of life.

Do not install modification kits with power applied to the drive. Disconnect and lockout incoming power before attempting such installation or removal. Failure to observe this precaution could result in severe bodily injury or loss of life.

The drive contains ESD (Electrostatic Discharge) sensitive parts and assemblies. Static control precautions are required when installing, testing, servicing, or repairing the drive. Erratic machine operation and damage to, or destruc- tion of, equipment can result if this procedure is not followed. Failure to observe this precaution could result in bodily injury.

The user is responsible for conforming with all applicable local, national and international codes. Failure to observe this precaution could result in damage to, or destruction of, the equipment.

These instructions are intended for qualified electrical per- sonnel familiar with servicing and installing AC drives. Any questions or problems with the products described in this man- ual should be directed to your local Carrier Service Office.

Wiring diagrams in this publication are for reference only and are not intended for use during actual installation; follow job specific wiring diagrams.

Do not attempt to start compressor (even for a rotation check) or apply test voltage of any kind while machine is under dehydration vacuum. Motor insulation breakdown and serious damage may result.

Low oil level may result if the oil pump is manually oper- ated for more than a few minutes when the chiller is not running. The oil reclaim system does not return oil to the sump when the compressor is de-energized.

GROUNDING THE CONTROLS/DRIVE ENCLOSURE — Use the following steps to ground the drive.

1.Open the left door of the control center.

2.Run a suitable equipment grounding conductor unbroken from the drive to earth ground. Tighten these grounding connections to the proper torque. See Fig. 6 and 29.

3.Close the door to the control center.

INSTALLING INPUT POWER WIRING — All wiring should be installed in conformance with the applicable local, national, and international codes (e.g., NEC/CEC). Signal wiring, control wiring, and power wiring must be routed in separate conduits to prevent interference with the drive operation. Use grommets, when hubs are not provided, to guard against wire chafing.

Use the following steps to connect AC input power to the main input circuit breaker:

1.Turn off, lock out, and tag the input power to the drive.

2.Remove the input power wiring panel above the VFD circuit breaker and drill the number of openings for the AC input leads (refer to Fig. 6). Mount all conduit hard- ware on the input power wiring panel before re-installing the input power wiring panel on the VFD enclosure. Take care that metal chips and hardware do not enter the enclosure.

3.Wire the AC input leads by routing them through the openings in the input power wiring panel.

Do not route signal and control wiring with power wiring in the same conduit. This can cause interference with con- trol and drive operation. Failure to observe this precaution could result in damage to, or destruction of, the equipment.

4.Connect the three-phase AC input power leads (per job specifications) to the appropriate input terminals of the circuit breaker. See Fig. 6.

5.Tighten the AC input power terminals and lugs to the proper torque as specified on the input circuit breaker.

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