Meter not running right?
Guide for meters used with instrument transformers
|
The problem is: |
Try this: |
| No reading |
- Check Current Transformer (CT) short circuiting devices. They may be open.
- Be sure the meter is getting voltage.
- Verify correct polarity on all CT's.
- Verify at least 5% rated current on CT's.
|
| Low reading |
- Look for 1 or more CT closed short circuiting device.
- Verify correct polarity on all CT's.
- Be sure voltage and current to each stator is from the same phase.
- Check register reading. Both last and present.
|
| Present reading lower than last |
- Look for reversed polarity on CT's or PT's.
- If disk rotation is OK, verify register readings. Maybe usage has not yet caught up with last month's too high reading.
|
