Document No. 125-1902
User Guide
June 26, 2018
Page 14 of 16 Siemens Industry, Inc.
Dimensions
Figure 19. Dimensions in Inches (Millimeters).
Troubleshooting
WARNING/AVERTISSEMENT:
Do not open the actuator.
Ne pas ouvrir le servomoteur !
The Economizer Controller/
Mechanical
Cooling is not operating
Use a multi-meter to check if there is 24 Vac +/- 25% (18 Vac – 30 Vac) at
the POWER terminals.
If there is no voltage or if the voltage is significantly low, check the
transformer output voltage at the RTU. If 24 volts is not present at the
transformer secondary side, check the primary line voltage to the
transformer.
If the line voltage is not present at the transformer primary side, check the
primary power to the RTU, fuses, circuit breaker, and so on.
If voltage is below 18 Volts, the Economizer Controller may be in Brownout
Protection mode. This mode disables all of the relay outputs.
When the power is back to 18 Vac or higher, the Economizer Controller and
RTU will operate normally.
Y1/Y2 signal is missing
from the thermostat
Mechanical Cooling doesn’t run until there is cooling demand (Y1/Y2 Active).
Check the wiring from CC1, Q11 and CC2, Q21 terminals to the commercial
thermostat. 24V should present between CC1.Q11/CC2.Q21 and COM.
24 Vac~ and 24 Vac ┴
are incorrectly wired
24 Vac power supply has polarity when all devices are powered by the same
24 Vac transformer; reversing polarity may cause a short circuit that can
damage the system.
Follow the transformer polarity mark; check the wring of 24V~ (or G or 24V+)
and ensure that they are tied to the same polar of 24 Vac power supply;
while checking the wiring of ┴ (or G0 or 24V- or COM) and ensure that they
are all tied to another polar of 24 Vac power supply.
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