The difference b/w voltage imbalance and phase loss
The difference b/w voltage imbalance and phase loss
(OP)
members,
What is the difference b/w voltage imbalance and phase loss
What is the difference b/w voltage imbalance and phase loss






RE: The difference b/w voltage imbalance and phase loss
VOLTAGE IMBALANCE is when one or more phase voltages are significantly different. For instance 208, 208, 200. This is of course far less serious but will still result in shortened motor life if it is a chronic problem.
As you probably know you can buy Phase Monitors that allow you to set the percentage/voltage imbalance allowed between phases before triggering a motor disconnect. Of course a phase loss will be concidered a bad phase imbalance and trip out also.
RE: The difference b/w voltage imbalance and phase loss
MIL-STD-1399(NAVY)
SECTION 300A
13 October 1987
SUPERSEDING
DOD-STD-1399(NAVY)
SECTION 300
1 August 1978
(See 6.3)
""MILITARY STANDARD
INTERFACE STANDARD FOR
SHIPBOARD SYSTEMS
SECTION 300A
ELECTRIC POWER, ALTERNATING CURRENT"
RE: The difference b/w voltage imbalance and phase loss
It may be appropriate to consider phase loss as an extreme case of voltage imbalance. Further, it may be reasonable to consider phase reversal as even more extreme a case of voltage imbalance.
RE: The difference b/w voltage imbalance and phase loss
This can cause problems with loss of phase detection. Sometimes it is better to sense for loss of current than loss of voltage. Also, voltage imbalance can be detected with a negative sequence overvoltage (ANSI 47) device.
http://basler.com/php/download.php?file=practical.pdf&i...