RF (?) Interference

[Jimbo]

Ok, so not on a Landy - but on my TV at home !

I changed the shower and pump, used the same fused spur and now when the pump runs I get flickering marks running across the TV screen. The interference was not present with the old pump.

Anyone got any suggestions ?

I've spoken to the manufacturer, they suggested 'uncrossing any crossed cables'...... :roll: , but nothing is crossed !

Ta,
Jim

[Wanderer]

I don't have the answer for you but the avenue you need to be going down is EMC.
ElectroMagnetic Compatibility
The shower should be EMC compatible and there are regulations.
It could be a poor connection but with X KW running to the shower I'd doubt it unless it's on the pump side of things.

Is everything earthed properly.
Laws that came out in January this year mean that you can't fit it yourself so your comeback should be with the manufacturer or the installer.

Ed

[muddysteve]

I don't have the answer for you but the avenue you need to be going down is EMC.
ElectroMagnetic Compatibility
The shower should be EMC compatible and there are regulations.
It could be a poor connection but with X KW running to the shower I'd doubt it unless it's on the pump side of things.

Is everything earthed properly.
Laws that came out in January this year mean that you can't fit it yourself so your comeback should be with the manufacturer or the installer.

Ed

As a sparky ive seem loose conections cause this lots of times, make sure the fuse spur connections really tight

as far as you not being able to do it yourself i think you'll find that connecting to a fused spur isnt classed as working on the "fixed wiring installation" and therfore can be done by anyone

Steve

[Jimbo]

Cheers for the replies, I too was thinking along the lines of EMC - the new pump is CE marked, and the spur is fused at 3A (as per the instructions) - it's not a 'power shower', just a pumped hot and cold system.

I'm going to double-check the wiring today, and run a temporary (plug on the shower and extention lead) supply in case the problem is with the wiring to the spur.

What concerns me slightly is that when I spoke to the manufacturers 'helpline' yesterday, they mentioned about checking for 'crossed wires' and said that they may have to raise a field call and get an engineer to fit a cage.......I'm assuming that they have had this problem before, and have some sort of Faraday cage thing that bolts around the pump - not what SWMBO wants in her airing cupboard  :(

Jim

[Hightower]

I changed the shower and pump, used the same fused spur and now when the pump runs I get flickering marks running across the TV screen.

You're a bit posh aren't you Jim, having a TV in the shower ? ? ? ?

[Jimbo]

Simon,

You jest - SWMBO did initially want a TV in the bathroom, but when I saw the prices, I suggested that a battery powered portable would be more suitable  

Anyone know how to build a Faraday cage  :?


Jim

[Miniman]

Simon,

You jest - SWMBO did initially want a TV in the bathroom, but when I saw the prices, I suggested that a battery powered portable would be more suitable  

Anyone know how to build a Faraday cage  :?


Jim

The front door on an old Microwave is The Faraday Screen. which would be a good Idea for the screen on the tv. All you have to do with the rest is case it in with a tin box. I can see some Garage time coming in...

[Jimbo]

I was planning (if nothing easier works !) on building a cage around the shower pump - is it just a metal box thats bonded to earth ?

Jim

[Miniman]

I was planning (if nothing easier works !) on building a cage around the shower pump - is it just a metal box thats bonded to earth ?

Jim

Yes that is correct. GOOD EARTH. Have you not thought that the shower may be faulty. It may be worth taking it back and getting it exchanged. There is nothing to lose besides the shower for an hour. May be worth a try.

[NeilWilson]

Faraday cages have a mesh size relative to the frequency you are trying to shield from - ie at a particular freq a bit of chicken wire fence does not work as well as microwave door screen etc .

One of the main disturbances we found on a tv/radio in our first house was the central heating motorised valve controller had a relay where the internal contacts were breaking down & becoming resistive thus sparking each time the motor reversed.

There are some filters/shunts that can go across terminals - bit like car ignition suppressors - I think Maplin/RS had some.  Cheers.

Neil

[Jimbo]

Agreed, the shower may be faulty - but the bathroom shop it came from did an overnight flit the other week, but then it is from a well known manufacturer so I may well go down that route if nothing else works !

The type of interference - 'sparkles' running horizontally across the TV screen - would appear (according to the t'interweb) to be mains borne, so I suspect that the pump motor is the cause, perhaps not enough suppression or something !!!

Jim

[Wanderer]

You could try a ferrite rod or ferrite ring and wrap the mains lead to the TV around the rod or ring. It might take it out.
Using a ferrite ring on the mains supply to the shower might be a bit more difficult.