How to reduce EMI noise in power line caused by electric welding

[prince213]

hi,
i have a single phase power supply coming to home & several welding shops are there in my locality using the same line so EMI noise & minor voltage fluctuation are there on the power supply when they are working which is affecting computer. ups seems to jitter (avr) almost all the time due to this.

can i do something to solve this issue using some electronic circuit like filter or something like that placing before power enters to computer ?

thanks

 

[hamidmoallemi]

I think you dont have EMI noise problem because the computer hardwares has good immunity against that,and also the metal case of pc reduces it
I think your problem is fluctuations and your pc power supply shuld manage it if they are small,
but you may need Stabilizer circuit before your power supply of pc,or you can change your power supply of pc and get a better one,

 

[prince213]

Thanks for the reply, the problem is due to the annoying heavy switching action of ups which is probably due to voltage fluctuations caused by that welding transformer. i tried to place a voltage stabilizer (digital one) before the ups but at that time both stabilizer & ups keeps on switching due to their internal automatic voltage regulation. ups sensitivity is higher than voltage stabilizer. i also tried using a analog voltage stabilizer by manually step upping voltage to higher levels in this case too its not solving my issue.

 

[dick_freebird]

Call your power company and complain about brown-outs.
Maybe the line is not up to the load and one of your
neighbors needs to get their own feed. The power
company will take care of that, they like money.

Or get a UPS that advertises a continuous operation (not
"off mains when able", but full time inverter output) and
a wider line range.

 

[prince213]

i have repeatedly filed complaints to them & they told to ignore such things as its a goverment electricity board and we have no other electric companies to switch like different mobile companies.

can circuit like this solve this issue to some extent

in this circuit is the x2 capacitance value marked .15 uF ?

thanks a lot for all the replies

 

[neutrino]

Yes, the X2 capacitor is 0.15uF (150nF). This is an AC power line filter, and in gereral is used in opposite direction, to limit the conducted emission from devices to AC mains (opposite direction). It may not work peroperly.