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TV Screen Flickers When Turning on Fan in the Hall

05/13/2017 2:34 AM

Hi,

when i turn on my fan in the hall, the tv flicker but some time it go blackout

then come back by it own.

The fan and tv is wire in different circuit back to main distribution board.

can someone help.

thanks.

David.

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#1

Re: TV screen flickers when turning on fan in the hall

05/13/2017 2:59 AM

Your fan may have a short or you may have a loose connection somewhere....The first place to check is to wiggle the wires and breakers in the distribution box to see if anything, like the tv, flickers....you could have a loose connection on the power side or the neutral side, so basically you have to start at the distribution box and work your way to the fan and tv...If you have an infrared thermometer a loose power connection will heat up, may spark or be discolored...a loose connection on the neutral will just spark...You may want to check the amp draw on each circuit if you have an amp meter, and especially the fan circuit on startup...It's a good idea to wear some thick heavy rubber gloves when working around live wires...and eye protection doesn't hurt...

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#2

Re: TV screen flickers when turning on fan in the hall

05/13/2017 3:28 AM

Hi,

i have check the circuit wiring ,no loose connection.

The only thing i found is the ring circuit is not wire properly.

will this the issue?

thanks

David

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#3
In reply to #2

Re: TV screen flickers when turning on fan in the hall

05/13/2017 12:21 PM

Yes possibly the wire size is too small for the load, what do you mean by improperly? In any case you need an amp meter to check the amp draw against the wire size....you may need to reduce the load, reconfigure the wiring, or increase the wire size....

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#7
In reply to #3

Re: TV screen flickers when turning on fan in the hall

05/14/2017 5:45 PM

I suggest that a clip-on ammeter would be easiest to use--I wish I had one. This would avoid breaking the connections for the test. But breaking the connections would help ensure that they were clean and not corroded.

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#10
In reply to #3

Re: TV screen flickers when turning on fan in the hall

05/15/2017 3:21 AM

Ahem, er, the Original Poster has already indicated that the two loads are on different circuits. Just sayin'.

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#11
In reply to #2

Re: TV screen flickers when turning on fan in the hall

05/15/2017 4:12 AM

<...the ring circuit is not wire properly...> Then correct it.

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#4

Re: TV Screen Flickers When Turning on Fan in the Hall

05/14/2017 5:03 AM

“The only thing i found is the ring circuit is not wire properly.”

In what way is the wiring wrong?

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#12
In reply to #4

Re: TV Screen Flickers When Turning on Fan in the Hall

05/15/2017 9:54 AM

Hi tony,

if is ring circuit when i take out one wire at the mcb should not give me a power supply cut off at that ring.

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#13
In reply to #12

Re: TV Screen Flickers When Turning on Fan in the Hall

05/15/2017 12:20 PM

You could just plug a 100watt lightbulb lamp where the tv is plugged in and see if it dims when fan is energized....this would tell you if it's an RF interference or a power deficiency situation...

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#5

Re: TV Screen Flickers When Turning on Fan in the Hall

05/14/2017 8:02 AM

I too, wonder what is improper in the wiring. facts would help.

It was stated that the two devices are on different circuits but is there any "sneak connection" that affects both, such as common ground or neutral?

Several suggestions have considered the supply voltage but no one has asked about the RF signal to the TV. I have found many problems in my home, due to poor installation of old cable/satellite prior to my purchase of the home. The original Cable installer had not made up the RG connectors correctly and the shield was not continuous. I went for an over the air antenna with amplifier when I bought the house. It would work most of the time, but had a lot of interference when various electrical loads switched on and off due to odd frequencies generated. Occasionally the TV would go black except for text that said "digital signal lost." The 120 volt wiring to the TV and other circuits was fine, but the RG cable was so bad, I finally cut off all the connectors and put on new terminations. The last problem I found was when, because some arms of my antenna had blown off, I ordered a new, cheap antenna with a Rotator to pick up some close by channels. and had intended to order a new large fringe antenna. When I plugged the tiny antenna in it not only picked up the local stations perfectly, but when properly oriented, it picked up the stations I normally watch, about 100 miles away. The initial test was with the antenna set on the roof in a plastic bucked with a few bricks for support. Rube at his best, and the antenna wire looped through a window and direct connected to the TV. proving the tiny antenna would work, I removed it and plugged the cable from my existing, properly installed, but wind damaged large antenna and the signal was great, for about 90 minutes. I got up and reached back and wiggled the cable and d the signal came back. I cut off the cable end and installed a new one, even though it was one I had replaced earlier. The problems persisted, off and on. I finally traced it to a cold solder joint in the back of my almost new Sony digital flat screen,. Again the shield side of the connector. A simple fix except for the exercise of taking the unit off of the bracket and back on again. The tiny antenna, even though it worked, is sitting in my crawl space. The local stations were not worth watching.

I have now had great reception and the only problem lately was a device I had just bought that caused interference lines. The manufacturer replaced that without any problems and all is well now.

The point I am trying to make, is that the symptoms the OP gave could be signal rather than supply voltage, and the fan could be generating an interference RF signal that is somehow getting to the TV. What is source of standard RF signal: Cable, Satellite, Roof antenna, or indoor antenna?

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#6

Re: TV Screen Flickers When Turning on Fan in the Hall

05/14/2017 10:12 AM

For any ambient induced, related noise problems such as yours;

The very first thing I will do is to check and validate the integrity of all input signal connection(s). Tracing it starting From the signal sources, like cable, antenna, etc. to the TV set.

Making sure that all coax cables are properly terminated, intact (no breaks /interruptions) with the shields, (ground wire), properly grounded to the tv chassis!

Properly grounded coax cable shields to either thru the cable box, main water supply pipe, sharing same polarity with power ground..

A note of caution on safety:

Depending on the vintage of the TV, some make / models may still have a two prong polarized power plug! TV chassis not wired directly to the "hot" power side, minimizing shock hazards!

Good luck!

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#8

Re: TV Screen Flickers When Turning on Fan in the Hall

05/14/2017 5:54 PM

I'm not an electrical person at all. However I have heard that all electric motors are pretty much a dead short at the instant they are started, thus sucking a lot of amps when starting which causes a sag in system voltage, thus the flicker in the TV. But both very soon return to normal when the motor gets up to speed--quite rapidly for small motors. But I wouldn't expect much effect from a small fan motor.

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#9

Re: TV Screen Flickers When Turning on Fan in the Hall

05/15/2017 3:17 AM

<...can someone help...> Yes, indeed: engage a qualified local Electrician. These people have the experience and qualifications to effect remedies. One is also buying a warranty that comes with the final test record document that will satisfy the building's fire insurance company.

Many of them advertise.

They can even be found in the local area telephone directory.

http://cr4.globalspec.com/thread/112363/Residential-Wiring

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