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Power Factor Over Correction Effect On Meters
2

Power Factor Over Correction Effect On Meters

Power Factor Over Correction Effect On Meters

(OP)
What is the effect of overcorrecting power factor on meters.  

RE: Power Factor Over Correction Effect On Meters

If you're referring to a watthour meter such as a utility would use a billing meter, the power factor, leading or lagging should not have a direct impact, since the meter is designed to register only real power.

However, overcorrection has two side effects - one is to increase the current flow above what it would be at a unity power factor.  This increased current creates some additional losses in the system cabling, although this is a secondary effect and the impact is usually low.

The second issue is that overcorrection can cause your bus voltage to increase.  Resistance loads such as strip heaters, electric boilers, etc will draw more power as voltage is increased.  However, since these are generally thermostatically-controlled, the impact is generally not significant.  Incandescent lighting will also draw more power at higher voltage, but it's not used much anymore, so probably not an issue.  

RE: Power Factor Over Correction Effect On Meters

Higher voltage will cause induction motors to draw more current above about 105% of nameplate voltage (nameplate=460 then at around 483volts the current will be higher than it would be at 460 with the same load).
I am in agreement with dpc on meters if your talking about metering for the purpose of billing. However, their may be PF penalties. I have not heard of penalties for pf above one but I bet they exist like penalties for pf less than one. The utility still has to provide VAR support for pf's other than one.

RE: Power Factor Over Correction Effect On Meters

Buzzp is correct, utilities can and do charge a penalty for leading power factor as well as lagging.  Here in the Pacific Northwest, Bonneville Power Admin (a wholesaler) charges a penalty for power factor lower than 0.97 in either direction.  

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