ghost in the machine

[fisbn]

A client called me today and said that every time he outs on the microwave his TV goes on mute,sometimes with the dryer too.He doesn't think the tv and micro are on the same circuit.I haven't got out there yet.
any ideas?
larry

 

[electricalperson]

edited: didnt see you said mute.

 

[electricalperson]

this sounds pretty interesting. could the current inrush of a microwave or dryer cause some kind of distortion on the lines causing it to go mute?

 

[cowboyjwc]

Check for a lose or bad phase conductor or a bad main breaker.

I can never remember when you check if you'll get 110 on one phase and 0 on the other and 220 across or if you get 110 and 110 and 0 across.

I had the same thing in a house turn on the tv then go in the bathroom and turn on the light and the tv would go off and the kitchen fan would go on. All kinds of wierd things.

 

[K8MHZ]

Check for a lose or bad phase conductor or a bad main breaker.

I can never remember when you check if you'll get 110 on one phase and 0 on the other and 220 across or if you get 110 and 110 and 0 across.

I had the same thing in a house turn on the tv then go in the bathroom and turn on the light and the tv would go off and the kitchen fan would go on. All kinds of wierd things.

That sounds like an open neutral.

 

[Lxnxjxhx]

open neutral

open neutral

I don't see what else it could be.

 

[LarryFine]

I can never remember when you check if you'll get 110 on one phase and 0 on the other and 220 across or if you get 110 and 110 and 0 across.

The former can't happen, and the latter is an open phase, with the second line voltage coming through line-to-line loads.

With an open neutral, you get almost anything between either phase and neutral, but the two phase-to-neutral voltages' total, and line-to-line voltage, are both 240.

 

[cadpoint]

Ask the client to search consumer reports for there model & year of their microwave.

All I can think about this thread is RF screaming from the microwave.

The microwave is about to die, jmo ...

 

[cowboyjwc]

Thanks Larry.

With an open neutral you can usually tell that's what it is because the lights tend to get brighter every time a load is added.

 

[Lxnxjxhx]

You can confirm an open neutral by measuring between any neutral or ground terminal at a receptacle and a cold-water-pipe earth ground. You may need to run an extension cord to pick up the nearest earth ground.

More than, let's say, 2 v between these two points means open.
This method is based on the very likely occurrence of unequal loads on both sides of neutral.

 

[Lxnxjxhx]

ghost in the machine = ?

ghost in the machine = ?

"God out of the machine" describes an artificial, or improbable, character, device, or event introduced suddenly in a work of fiction or drama to resolve a situation or untangle a plot (such as an angel suddenly appearing to solve problems).

http://en.wikipedia.org/wiki/Deus_ex_machina

Yeah, I'm sure that's what you meant. . .