HDWA-SVX001D-EN
57
AFD Mains Phase Loss
The following figure shows how the controls act in a
power interruption event that the Adaptive
Frequency
™
Drive (AFD) diagnoses as a AFD Mains
Phase Loss (MPL) diagnostic.
Figure 41.
Sequence of events: AFD mains phase loss
“AFD Mains Phase Loss” From Drive
(Controls Remain Powered)
“AFD Mains Phase Loss”
Cleared and Need to Cool
Running
Starting
Compressor
Shutting Down
Waiting to Start
Close IGV (0 to 50 Seconds)
Establish Condenser and Evaporator
Water Flow (6 Second Filter)
No Evap Pump Off Delay
for Immediate Shutdown
De-Energize
Compressor
De-Energize Evaporator
Water Pump Relay
De-Energize
Condenser Water Pump
Close Economizer EXV
Close Motor Cooling
Valve
(200 and 300 Ton Only)
Close Drive Cooling
Valve
Close IGV
Energize Evaporator
Water Pump Relay
Energize Condenser
Water Pump Relay
Evaporator
EXV Pre-position