Carrier 69NT40-541-001 Operation And Service page 118

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. 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.
7.20.2 Controller Trouble-Shooting
A group of test points (TP, see
(see schematic diagram,
Use a digital voltmeter to measure ac voltage between TP's and ground (TP9), except for TP8.
TP2
This test point enables the user to check if the internal
protector for the compressor motor (IP-CP) or high
pressure switch is open.
TP3
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.
7.20.3 Controller Programming Procedure
To load new software into the module, the programming card is inserted into the programming/software port.
The unit must be OFF whenever a program ming card is inserted or removed from the control-
ler programming port.
a. Procedure for loading Operational Software
1. Turn unit OFF, via start-stop switch (ST).
2. Insert the programming card for Operational Soft ware into the programming/software port. (See
menuDDMM.ml3, this file allows the user to select a file/program to upload into the controller.
cfYYMMDD.ml3, multi-configuration file
3. Turn unit ON, via start-stop switch (ST).
4. The Display module will display the message ruN COnFG. (If a defective card is being used the Display will
blink the message "bAd CArd". Turn start-stop switch OFF and remove the card.)
5. Press the UP or DOWN arrow key until display reads, LOAd 54XX for Recip (even numbers).
6. Press the ENTER key on the keypad. The Display will alternate to between PrESS EntR and rEV XXXX
7. Press the ENTER key on the keypad. The Display will show the message "Pro SoFt." for up to one minute.
8. Press the ENTER key on the keypad.
T-316
Figure 7.24) are provided on the controller for trouble-shooting electrical circuits
Figure 8.2). A description of the test points follows:
!
NOTE
TP 6
This test point enables the user to check if the control-
ler 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 ter-
mination thermostat (HTT) contact is open or closed.
- - - - -
CAUTION
7–30
Figure 7.24):