On the display
The YMC2 display shows Incorrect Voltage Values on the VSD Details Screen. The manual prints the message only in this wording, and it is listed under the output line voltage isolation board symptoms for this model. Separate VSD messages for the YMC2 include WARNING - VSD - DC Bus Active and VSD - DC BUS LOCKOUT - DO NOT CYCLE POWER; they are different messages and are not covered here.
What it means
The values shown on the VSD details screen are incorrect. The Phase A output voltage signal is the one used for the speed reference; Phase B and Phase C are displayed on the VSD details screen for reference only and do not impact the drive operation. All phases of output voltage should be balanced, so unbalanced or wrong readings on this screen are what the message is reporting.
Why it appears
- Phase B or Phase C transformer failure. The manual states that if one of these transformers were to fail, the result would be incorrect values on the VSD details screen, but the machine could still operate.
- The output line voltage isolation board. The manual treats this board as one possible source of the message.
- Other conditions. Multiple conditions could generate this message in addition to the output line voltage isolation board; the manual does not enumerate them here and directs diagnosis to the drive service manual.
What to check
- Use the drive service manual to help determine the source of the issue, since more than one condition can produce this message.
- Check the condition of the three fuses supplying the output line voltage isolation board
regardless of the fault experienced
. - If the output line voltage isolation board is suspected, check its primary and secondary windings as described in Tables 1-4 of the manual.
Questions engineers ask
What does Incorrect Voltage Values on the VSD Details Screen mean on a YORK YMC2?
It reports that the values shown on the VSD details screen are incorrect. Phase A output voltage is the signal used for the speed reference, while Phase B and C are displayed for reference only and do not impact drive operation; all phases should be balanced.
Can the chiller keep running with this message active?
Yes, in the case the manual describes: if a Phase B or C transformer fails, the screen shows incorrect values but the machine could still operate.
What should I check first on a YMC2 with this VSD voltage message?
The manual first refers you to the drive service manual to help determine the source of the issue. It also says to check the three fuses supplying the output line voltage isolation board regardless of the fault experienced.
Does this message always mean the output line voltage isolation board has failed?
No. The manual notes that multiple conditions could generate this message in addition to the board; if the board is suspected, its primary and secondary windings can be checked (Tables 1-4).
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