Installation Manual PA Pro III
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2018-03-16 Page 29 of 30
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A configured 1-wire sensor is showing -999.99°C
PA Pro III has lost connection with the sensor. Check wiring, topology and weight of the 1-
wire bus. Check section 7 for more info.
12.4
Power measurement
In case of trouble with the power measurement, please refer to the suggested actions described in
this section.
12.4.1
Supply voltage
If the power meter display does not light up, then there is no adequate voltage supply to the power
meter.
Note that the EM24 is powered from the main housing voltage supply, and the EM210 is powered
from the measured voltage on phases L2 and L3.
12.4.2
Communication
If the power meter displays measured values but the PA Pro does not show any data:
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Check that the RS485 cables are connected as shown on the provided wiring diagram, both
on the power meter and the PA Pro. Make sure that the they are connected tightly.
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Check that the Modbus address is correct and the baudrate is set to 9600. Follow sections
9.2 and 10.2 for more details.
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Make sure that there is adequate voltage supply to the power meter. The unit may be
powered on, but the Modbus communication will not function properly without correct
voltage supply.
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Make sure that the PA Pro configuration is set correctly. Contact ClimaCheck support for
more help.
12.4.3
Measurement
Experience shows that the biggest challenge for ClimaCheck users is to apply power measurements
correctly. Outmost care is recommended when applying sensors as it can often be difficult to follow
cables in confined housings.
Always compare measured currents and power with rating plates and/or nominal data at start of
measurements.
Make sure that the CT configuration is set correctly on the power meter. Check section 4 for more
details.
Check the following on the power meter display:
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Current
If current is unbalanced, check that clamps are fully closed. If wrong level, check CT
configuration and make sure that the complete compressor current and only compressor
current is measured. Typically, current per phase is not allowed to vary so that any phase
deviate more than 10% from the average for a three-phase motor.
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Voltage
Typically, voltage per phase is not allowed to vary so that any phase deviate more than
10% from the average for a three-phase motor.
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Power per phase
If the power is uneven check the above points about current and voltage. If any power is
negative but voltage and current are correctly matched, the CT is turned in the wrong
direction or wires between CT and meters are crossed.
