Industrial Climate Engineering SlimPac ECUA12 Installation & Operation Manual page 23

2. Running Amperage: Connect a clip-on type ammeter to the (common) lead to the compressor.
Turn on the supply voltage and energize the unit. The compressor will initially draw high amperage;
it should soon drop to the RLA value or less. If the amperage stays high, check the motor winding
resistances.
NOTE: Feel the top of the compressor to see if it has overheated. If it is hot, the internal overload
may be open. You may have to wait several hours for it to reset.
3. Motor Winding Resistances: Using a digital volt-ohm meter (VOM), measure the resistance
across the compressor windings as shown below.
Resistance can be measured as shown above. Any deviation from above values could indicate a
defective compressor.
4. High Voltage/Insulation Test: Test internal leakage with a megoh meter. Attach one lead to the
compressor case on a bare metal tube and to each compressor terminal to test the motor windings.
A short circuit at high voltages indicates a motor defect. Do not do this test under vacuum.
SINGLE C
PHASE
R
R
R
2 1
R
R
S
R
3
23
> R > R
3 2 1
= R + R
3 2 1
ICE SlimPac ECUA12-18 I&O Manual 03/2019 Rev.2