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Why does the monitored RPM not match the actual motor speed on the ATV212 drives?

Issue:
Customer is looking at the RPM value in the monitor menu and it does not match the actual RPM

Product line:
Altivar 212, ATV212, S-Flex

Environment:
all

Cause:
Parameter F856

Resolution:
The default setting for parameter F856 is 2 (4 pole motor).  You may need to change the number of motor poles to see the correct RPM value returned on the display.

F856 can be set to:
1 - 2 poles
2 - 4 poles (default)
3 - 6 poles
4 - 8 poles
5 - 10 poles
6 - 12 poles
7 - 14 poles
8 - 16 poles

Note that the displayed value is based on nominal RPM and output frequency.  It does not take motor slippage into account.  The VFD does not monitor the actual motor RPM.
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