Trane RAUC-IOM-15, Инструкция по установке и обслуживанию

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System Pre-Start Procedures (Continued)
6. To simulate a call for maximum reset, remove the jumper
from Terminals 6 & 7 and install the 1780 ohm resistor
(red leads), from the test kit, across Terminals 6 and 7.
7. Install a jumper across the P1 and P2 Terminals (remote
setpoint input).
8. Remove the red dust cover from the test plug socket at
the bottom of the W7100G. Insert the “Test Plug”, from
the kit, into the test plug socket. The test plug overrides
most of the built-in time delays for staging the compres-
sors “On” and “Off”. Refer to the illustration in Figure 4-4
for terminal and control dial identification.
9. Set the “Reset F” dial at 20 o F and the “Setpoint F” dial at
10
o
F
10. “Close” the main power disconnect switch and turn the
control circuit switch 1S2, in the unit control panel, “ON”.
H A Z A R D O U S V O LTA G E !
HIGH VOLTAGE IS PRESENT AT TERMINAL BLOCK
1TB1 OR UNIT DISCONNECT SWITCH 1S1.
To prevent injury or death form electrocution, it is
the responsibility of the technician to recognize this
hazard and use extreme care when performing ser-
vice procedures with the electrical power energized.
11. At the Chilled Water Controller, use a digital voltmeter to
verify there is 24 volts AC across terminals TR & TR.
12. After approximately 15 seconds, the LEDs on the
W7100G should begin to illuminate as the cooling out-
puts stage “On”.
13. Set the “Setpoint F” dial at 60
o
F; within 15 seconds, the
LEDs should turn “Off” as the cooling outputs stage “Off”.
14. Remove the 1780 ohm resistor from Terminals 6 & 7
and reinstall the wire jumper removed in step 6.
15. Set the “Setpoint F” dial at 50
o
F; within 15 seconds, the
LEDs should turn “On” as the cooling outputs stage “On”.
16. Turn the control circuit switch 1S2, in the unit control
panel, to the “OFF” position.
17. Remove the 3,400 ohm resistor from Terminals T & T1
and reconnect the chilled water temperature sensor
leads to Terminals T & T1.
18. Remove the “Test Plug” from the W7100G test socket
and reinstall the red dust cover.
19. Plug the reset relay(s) 1K11 and 1k12 (if applicable)
back into their receptacle.
20. Turn the control switch 1S2 to the “On” position to re-
store power to the control system.
Figure 4-4
W7100G Chilled Water Controller
Chilled Water Sensor Checkout
(Honeywell Sensor)
1. Verify that the main power disconnect switch and the
control circuit switch 1S2, in the unit control panel, is
“OFF”.
2. At the temperature controller, disconnect the wire con-
nected to terminal T1. Use a digital ohmmeter to mea-
sure the resistance across terminal T and the wire re-
moved from terminal T1.
3. Use the conversion chart in Table 4-1 to convert the mea-
sured resistance to an equivalent temperature.
4. Measure the actual temperature at the sensor location. If
the measured resistance in step 2 is not within ± 10.0
ohms of the actual temperature, the sensor is out of
range; replace it.
Note: Before condemning the sensor, verify that
the connecting cable resistance is not excessive.
Refer to the “Field Installed Control Wiring”
section.
5. Make all necessary repairs and reconnect the duct sen-
sor lead to terminal T1 on the controller.
6. Turn all control switches to the “ON” position and restore
power to the system.