Trane Tracer MP501 Installation, Operation And Maintenance Manual page 49

The analog output generates a 0–10 Vdc control signal used to control valve, damper, pump speed,
fan speed, and so on. The PID loop in the MP501 calculates a value between 0 and 100%. The
controller then translates that percentage into the output voltage.
typical analog output applications. This information will help to anticipate the voltage that is read,
given the PID output.
Table 20. Percent to voltage scaling for analog output
PID Output
0%
25%
50%
75%
100%
The troubleshooting steps in
always closed when the user believe it should be somewhat open and vice versa when closed.
Table 21. Analog output (0–10 Vdc) troubleshooting of external wiring
Step Number Action
Perform the initial troubleshooting steps described in
Step 1
operation is okay.
Inspect the wiring. Is there a good connection between the wire and the terminal blocks? Look
Step 2
for shorts or opens. Pay particular attention to wire splices.
Take your meter (set to measure dc voltage) and measure the voltage across the AO terminals
on the MP501.
Step 3 If you see a value greater than 0 V, the problem lies beyond the MP501. Is the wiring to the
equipment good? Is there a hardware override controlling the equipment?
If you see approximately 0 V, proceed to the next step.
Remove the wires from the AO terminals and measure the voltage again.
If you see a value greater than 0 V, there is a wiring or equipment problem external to the
Step 4 MP501.
If you still see approximately 0 V, the MP501 is commanding the output to be closed and you
need to investigate the MP501 further.
If the analog output is still not opening the end device, then follow the additional troubleshooting
steps in
output.
CNT-SVX08F-EN
Voltage Output
(0–10 Vdc Output)
0.0 Vdc
2.5 Vdc
5.0 Vdc
7.5 Vdc
10.0 Vdc
Table 21
Table 22, p. 50. These steps will assist the configuration and operation of the analog
Voltage Output
(2–10 Vdc Output)
2.0 Vdc
4.0 Vdc
6.0 Vdc
8.0 Vdc
10.0 Vdc
assume the end device connected to the analog output is
Table 17, p. 47 and verify general board
Troubleshooting
Table 20 lists the scaling for
Probable Cause
General board
problem.
Wiring problem.
Wiring problem.
Wiring problem.
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