DIYbanter - View Single Post - A/C on one circuit causing voltage flicker on another (?)

Tony Hwang

wrote:
On Tue, 29 Jul 2008 14:49:19 GMT, Tony Hwang wrote:

wrote:
This winter I installed a 16-circuit subpanel and rewired the second
floor. The sub is fed from the main via a 60A 250v circuit over 6/3.
Everything has been working fine ever since, but I haven't really been
pulling much on these circuits until this week.

Today I'm noticing that when one of my window A/C's compressor kicks
on it is flicking the lights. But these lights are on a different
circuit (same panel). I did not expect this. The A/C is pulling
about 10A (120v) on a 20A dedicated circuit. Other power being drawn
from this panel includes:

-computer: ~5A on a dedicated 20A circuit
-computer and extras: ~5A on a dedicated circuit
-another A/C: ~8A on a dedicated circuit
-lights: ~? (1A maybe) on another circuit

So total I doubt I'm drawing more than 30A of 120V, so I can't be
maxing out the feed, right? That feed should give me 96A of 120V (80%
of 60A at 240V).

So what's the deal? Why would any lights on a different circuit
flicker when the compressor kicks on on another circuit? To be fair,
the flicker is subtle. It's not huge, but it's there.

thanks
Hi,
Two things, momentary starting surge current is much higher.
#4 wire was better choice. Doing all this work, did you you take
out a permit? Just wondering. Where I live we need a DIY permit from
city and two inspections, during, after the work is done.

What are you a building inspector, or FBI agent. It's none of your
****ing business if he got a permit or not. Permits do not make
wiring any safer.

**** Off
Hi,
Don't get upset. This is a fact. A house suffered a fire damage. Cause
was electrical. When insurance company found out some wiring was done
w/o permit, they refused to cover the damage. DIY permit does not cost
much. I know it is none of my business.