Trane TTA075AD series, Установка, эксплуатация и обслуживание

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Test 4 - LED Indicator Test, (SYS ON, HEAT, & COOL)
Method 1
Testing the LED using a meter with diode test function. Test
both forward and reverse bias. Forward bias should measure a
voltage drop of 1.5 to 2.5 volts, depending on your meter.
Reverse bias will show an Over Load, or open circuit indication
if LED is functional.
Method 2
Testing the LED with an analog Ohmmeter. Connect Ohmme-
ter across LED in one direction, then reverse the leads for the
opposite direction. The LED should have at least 100 times
more resistance in reverse direction, as compared with the
forward direction. If high resistance in both directions, LED is
open. If low in both directions, LED is shorted.
Method 3
To test LED’s with ZSM connected to unit, test voltages at LED
terminals on ZSM. A measurement of 32 VDC, across an unlit
LED, means the LED has failed.
Note: Measurements should be made from LED common (ZSM
terminal 6 to respective LED terminal). Refer to the Zone
Sensor Module (ZSM) Terminal Identification table at the
beginning of this section.
Trouble Shooting
ReliaTel
TM
Controls
Programmable & Digital Zone Sensor Test
Testing serial communication voltage
1. Verify 24 VAC is present between terminals J6-14 & J6-11.
2. Disconnect wires from J6-11 and J6-12. Measure the volt-
age between J6-11 and J6-12, should be about 32 VDC.
3. Reconnect wires to terminals J6-11 and J6-12. Measure
voltage again between J6-11 and J6-12, voltage should
flash high and low every 0.5 seconds. The voltage on the
low end will measure about 19 VDC, while the voltage on
the high end will measure from approximately 24 to 38
VDC.
4. Verify all modes of operation, by running the unit through
all of the steps in the “Test Modes” section discussed in
“Unit Start-Up”.
5. After verifying proper unit operation, exit the test mode.
Turn the fan on continuously at the ZSM, by pressing the
button with the fan symbol. If the fan comes on and runs
continuously, the ZSM is good. If you are not able to turn
the fan on, the ZSM is defective.
RTCI Loss of communications
If the RTCI loses input from the building management system,
the RTRM will control in the default mode after approximately
15 minutes. If the RTRM loses the Heating and Cooling
setpoint input, the RTRM will control in the default mode
instantaneously. The temperature sensing thermistor in the
Zone Sensor Module is the only component required for the
“Default Mode” to operate.