ADTRAN T200 H2TU-R Installation And Maintenance Manual page 16

3. Disable the front door switch by centering the
rod and pulling outward. The secondary fan
board Door LED should go Off and the Door
Alarm LED at the FPU will turn green.
Fan Operation
When the cabinet is initially installed without heat
generating circuit packs, the primary and secondary
fans will not automatically turn On. Fan board
thermostats control the On/Off fan cycle when the
interior temperature reaches the thermostat's set
points.
• The primary thermostat Closes at about 110 F
increasing and Opens at about 80 F decreasing.
• The secondary thermostat Closes at about 150 F
increasing and Opens at about 120 F
decreasing.
• Thermostat set points may vary slightly from
stated temperatures.
When the primary and secondary fan boards are
initially wired and connected to the Central Office
FPU, both the primary and secondary fan board
thermostat (Green) LEDs should be On and the fans
should be Off. This indicates that both of the fan
board thermostats are Open.
If the thermostat was Closed, the thermostat LED
would be Off and the fans would be On (if the
temperature was within the thermostat's Closed
operating range). The thermostat LED's operation is
independent of the door switch status.
Verify Proper Connections
Test to ensure that changes to the primary fan board
will cause changes to the associated LEDs at the
Central Office FPU:
NOTE
This test specifies the rear door/primary fan
board. Test the front door/secondary fan
board by conducting a similar process.
1. Disable the rear door switch by centering the rod
and pulling outward. The primary fan board
Door LED should go Off.
WARNING
High voltages are present on exposed pins.
DO NOT contact exposed surfaces.
1 6
2. On the primary fan board, disconnect the JP1
connector by pulling the connector out of the
header. DO NOT PULL ON WIRES.
- At the Central Office FPU, the PRI FAN LED
will turn red (alarm condition). This verifies
the primary fan board connections are correct.
- If the PRI FAN LED at the FPU does not turn
red, the connections are incorrect.
- If the secondary FPU SEC FAN LED turns on
red, the circuits are crossed between the
cabinet and the FPU.
3. Align and reconnect the JP1 connector.
If the primary and secondary fan powering
cable pairs are reversed at either the Central
Office or at the cabinet, the primary fan will
still go On at 110 F but the Central Office
FPU will indicate that the SEC FAN is
running. This is an ALARM condition at the
FPU.
Abnormal Condition Turning the Secondary
Fan On
Any condition that causes the secondary fan to turn
On is considered abnormal. The following conditions
will allow heat buildup causing the secondary fan
thermostat to eventually Close:
• The primary fan cannot keep up with heat load.
• The primary fan or fan board is not functioning.
• The circuitry between the FPU and the primary
fan board has opened, shorted, or otherwise
malfunctioned.
• The FPU at the CO is not providing power to the
primary fan board.
• Additionally, the secondary fan thermostat may
not be operating properly.
Fan Board Troubleshooting
If troubleshooting a fan board malfunction, fan board
operation should be examined during the hottest time
of the day before the outside temperature drops.
The cabinet internal temperature may stabilize slowly
or quickly depending on the outside air temperature,
wind conditions, exposure to the sun, shading during a
particular time of day, and also the number of circuits
installed inside the cabinet.
Section 61150090L1-5A, Issue 1
NOTE
61150090L1-5A