Danfoss Turbocor TT Series, Service Manual

Page: 74 / 294

Table 4-10 Solenoid Coil Resistance Ranges
Voltage Power Resistance
24V 9.3W 56.25Ω – 68.75Ω
Figure 4-32 Compressor Cooling Solenoid Coil Cable Connector
4.6.3.2 Output Voltage to Solenoid Coils
1. Remove the Service Side Cover. Refer to Section 4.1.3.1 Service Side Cover Removal and Installation on
page 54.
2. The compressor must be running and make a call to enable the cooling solenoid coils for the LEDs to
turn on. The SMT Cooling Mode will indicate "inverter," "motor," or "motor and inverter" when the
software is sending the signal to the coils.
3. To ensure the Serial Driver is providing power to the solenoids, look for the Cool-L and Cool-H LEDs on
the Backplane. Refer to Figure 4-33 Backplane - Cool LEDs and +24V Test Points.
4. To determine if 24VDC is present at one or both solenoid coils, use a multimeter to test the back sides
of pins 1 & 3 and pins 5 & 6 of the cooling solenoid coils WHILE they are energized. Refer to Figure 4-32
Compressor Cooling Solenoid Coil Cable Connector.
Figure 4-33 Backplane - Cool LEDs and +24V Test Points
4.6.3.3 Cooling Path Blockage Inspection
1. Isolate compressor power.
2. Isolate the compressor and recover the refrigerant according to industry standards. Refer to Section 3.1
Refrigerant Containment on page 41.
3. Remove the Service Side Cover. Refer to Section 4.1.3.1 Service Side Cover Removal and Installation on
page 54.
4. Remove the actuators, solenoids, and orifices.
Page 74 of 294 - M-SV-001-EN Rev. H 1/23/2023