Carrier 69NT40-541-300, Операция и обслуживание, Страница: 108 / 152

6 − 20 T − 318
6.23 CONTROLLER
6.23.1 Handling Controller
CAUTION
Do not remove wire harnesses from con-
troller unless you are grounded to the unit
frame with a static safe wrist strap.
CAUTION
Unplug all controller connectors before
performing arc welding on any part of the
container.
The guidelines and cautions provided herein should be
followed when handling the Controller/DataCORDER
module. These precautions and procedures should be
implemented when replacing the module, when doing
any arc welding on the unit, or when service to the
refrigeration unit requires handling and removal of the
controller.
a. Obtain a grounding wrist strap (Carrier Transicold
P/N 07-00304-00) and a static dissipation mat (Carri-
er Transicold P/N 07-00304-00). The wrist strap,
when properly grounded, will dissipate any potential
electrostatic buildup on the body. The dissipation mat
will provide a static-free work surface on which to
place and/or service the controller.
b. Disconnect and secure power to the unit.
c. Place strap on wrist and attach the ground end to any
exposed unpainted metal area on the refrigeration
unit frame (bolts, screws, etc.).
d. Carefully remove the controller, refer to Section
6.23.4. Do not touch any of the electrical connections
if possible. Place the module on the static mat.
e. The strap should be worn during any service work on
the controller, even when it is placed on the mat.
6.23.2 Controller Troubleshooting
A group of test points (TP) (see Figure 6-25) are
provided on the controller for troubleshooting electrical
circuits (see schematic diagram, section 7). A
description of the test points follows:
NOTE
Use a digital voltmeter to measure AC voltage
between TPs and ground (TP9), except for TP8.
TP 1 − NA
TP 2 − This test point enables the user to check if the
internal protector for the compressor motor (IP-CP) or
high pressure switch is open.
TP 3 − This test point enables the user to check if the
water pressure switch (WP) contact is open or closed.
TP 4 − This test point enables the user to check if the
internal protector for the condenser fan motor (IP-CM) is
open or closed.
TP 5 − This test point enables the user to check if the
internal protectors for the evaporator fan motors
(IP-EM1 or IP-EM2) are open or closed.
TP 6 − This test point enables the user to check if the
controller water tank heater relay (TQ) is open or closed.
TP 7 − This test point is not used in this application.
TP 8 − This test point is not applicable to the units
covered herein.
TP 9 − This test point is the chassis (unit frame) ground
connection.
TP 10 − This test point enables the user to check if the
heat termination thermostat (HTT) contact is open or
closed.
1 2 3 4
1. Controller Software Programming Port
2. Mounting Screw
3. Controller
4. Test Points
Figure 6-25 Controller Section of the Control Box