On the display
The control center shows VSD - HIGH PHASE A MOTOR CURRENT in exactly this wording. The manuals place this message in the group of cycling shutdown messages, so it appears when the drive stops the chiller on a phase A motor overcurrent.
What it means
The message means that the phase A motor current exceeded the fault value listed for the model of drive installed on the chiller. The drive monitors the three motor currents with Hall-effect current sensors and compares their instantaneous values to the limit; a current in excess of the limit causes this cycling shutdown.
Why it appears
- Phase A motor current above the fault value listed for the given model of drive.
Setpoints and thresholds
- 776 Amps — phase A motor current fault value for drive model 490 (listed as 0490 in the second manual).
- 1086 Amps — fault value for drive model 744.
- 1317 Amps — fault value for drive model 0774; 1094 Amps and 2164 Amps are listed for the other drive models in the second manual's table.
- 90 minutes — three high motor current cycling shutdown faults on any phase within this period escalate: the third fault in the 90 minute period causes a Safety Shutdown.
Reset and restart
A single occurrence of this message is a cycling shutdown. If three high motor current cycling shutdown faults occur on any phase within 90 minutes, the third fault in that period causes a Safety Shutdown. For that case the manual states: If the safety shutdown occurs, the chiller can be restarted after the clear faults button is pressed.
No other reset for this message is described.
Questions engineers ask
What does VSD - HIGH PHASE A MOTOR CURRENT mean on a YORK YMC2?
It means the phase A motor current exceeded the fault value listed for the drive model on the chiller. The drive compares the instantaneous motor currents from its Hall-effect current sensors to this limit, and the excess current causes a cycling shutdown.
What current trips the VSD - HIGH PHASE A MOTOR CURRENT fault?
It depends on the drive model: 776 Amps for the 490/0490 drive, 1086 Amps for the 744 drive, 1317 Amps for the 0774 drive, with 1094 Amps and 2164 Amps listed for the other drive models in the manual's table.
How do I restart the chiller after VSD - HIGH PHASE A MOTOR CURRENT?
One fault is only a cycling shutdown. After a Safety Shutdown — three of these faults on any phase within 90 minutes — the chiller can be restarted once the CLEAR FAULTS button is pressed.
Why does the YMC2 go into Safety Shutdown after repeated high phase A motor current faults?
Because the third high motor current cycling shutdown fault on any phase within a 90 minute period causes a Safety Shutdown, after which the chiller restarts only when the CLEAR FAULTS button is pressed.
Messages next to this one
Source
Written from the manufacturer's manuals for the YORK YMC2; every number and designation on this page is checked against them before publication. The row of the manual this message comes from:
All YORK YMC2 messages: fault codes · YORK YMC2 documentation · YORK manuals