Autotransformer; 7.27 Controller; Handling Modules; Figure 7.18 Autotransformer - Carrier PrimeLINE 69NT40-561-200 Operation And Service Manual

7.26 AUTOTRANSFORMER

If the unit does not start, check the following:
1. Verify the 460 VAC (yellow) power cable is plugged into the receptacle (see
2. Verify that circuit breakers CB-1 and CB-2 are in the "ON" position. If the circuit breakers do not hold in,
check voltage supply.
3. Using a voltmeter, and with the primary supply circuit ON, check the primary (input) voltage (460 VAC). Next,
check the secondary (output) voltage (230 VAC). The transformer is defective if output voltage is not available.
Dual Voltage Modular
Autotransformer

7.27 CONTROLLER

7.27.1

Handling Modules

Do not remove wire harnesses from module unless you are grounded to the unit frame with a
static safe wrist strap.
Unplug all module connectors before performing arc welding on any part of the container.
The guidelines and cautions provided herein should be followed when handling the modules. These precautions
and procedures should be implemented when replacing a module, when doing any arc welding on the unit, or when
service to the refrigeration unit requires handling and removal of a module.
1. Obtain a grounding wrist strap (Carrier Transicold P/N 07-00304-00) and a static dissipation mat (Carrier
Transicold P/N 07-00277-00). The wrist strap, when properly grounded, will dissipate any potential static
buildup on the body. The dissipation mat will provide a static-free work surface on which to place and/or ser-
vice the modules.
2. Disconnect and secure power to the unit.
3. Place strap on wrist and attach the ground end to any exposed unpainted metal area on the refrigeration
unit frame (bolts, screws, etc.).
4. Carefully remove the module. Do not touch any of the electrical connections if possible. Place the module
on the static mat.
The strap should be worn during any service work on a module, even when it is placed on the mat.

Figure 7.18 Autotransformer

Circuit Breaker
(CB-2) 230-Volt
CAUTION
!
CAUTION
!
460 VAC Power
Receptacle
NOTE
7–29
Figure 7.18) and locked in place.
T-362