A/C on one circuit causing voltage flicker on another (?)

Jul 29, 2008 29 Replies

Depends upon the motor and its load. Some are less. Compressors tend to be a lot more. Check the nameplate on the AC. Look for "LRA".

Momentary dimming of lights on motor starting is quite normal. If it is a 120V motor, the lights on circuits on the opposite may brighten. Some lights are more sensitive to voltage fluctuations: lights partially dimmed are much more noticeable; full on incandescents are less noticeable.

I too, have read this often on these newsgroups and yet I know in NY at least, homeowner insurance policies protect homeowners against stupid things that they do themselves. Possibly it differs elsewhere, but I've never seen any proof of it

I recently read my policy in detail and found this clause under "Cancellation":

"Failure by the insured to comply with any Federal, State, or local fire, health, safety, building, or construction regulation, law, or ordinance with respect to an insured risk which substantially increases any hazard insured against within 60 days of written notification of a violation of any law regulation, or ordinance."

There is also another clause: "Increased hazard or material change in the risk assumed which we could not have reasonably contemplated at the time of assumption of the risk."

Take a closer look at your policy. Most likely your insurance company has covered their ass somehow in the event of a disaster as a result of poor craftsmanship.

Hmmm. Lights dimming. Blinking too (let's say).

One possible reason: light got dim enough that you can see the 60-cycles (or would that be 120 both brights and dims per second?).

David

What does LRA stand for? An acronym? Name of a manufacturer?

Thanks,

David

Yup! Inductive load sarting surge can be pretty high for a split second eyes can notice. Also main panel better be big enough as well to minimize the effect. Peak surge is as high as 2.8 times of normal current draw.

Hmm, Can you show here big initial reactive load (impedance) can change frequency via math?

Hi, Your eyes and digital display panel is not good enought to catch it. Digital scope or analog scope kinda instrument will show it proper.

That should be "Locked Rotor Amps", the maximum possible current drain.

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