• IMPORTANT: The thread you're reading / posting in, could be in a DIY electrical advice area. Please be aware of your local laws. You're not allowed to provide advice to, or seek advice from, DIYers and fellow professionals in some States, Countries, Countys etc with regards to some types of electrical installations or repairs. Keep that in mind. If it's against the law where you are - always get a professional electrician in to carry out the works instead of doing it yourself. The forum will not be held responsible for any outcome of any applications of any advice sought from it.
Advertisement - Content continues below
Advertisement - Content continues below

Discuss RCD Tripping Randomly When PC Plugged In in the DIY Electrical Forum area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:  American Electrical Advice Forum

Hi everyone

I have a frustrating problem which has recently developed.

I kept finding that my power was tripping. I could just reset it then everything was fine for a while then it would happen again. It might happen once per day or it might happen a few times or it might not happen at all for many days.

After many weeks of trying to find it I am sure I have narrowed it down to my PC. I used to leave this PC on most of the time and I had it on a smart plug that I could turn on remotely to boot it up if I ever needed to access it remotely. I have found that when the PC is plugged in (doesn't have to be on) there is a good chance the fuse will trip. This does generally, but not always tally with something else running, such as my saniflo kicking in within a downstairs bathroom. Again, this does not happen all the time, it could be fine for days.

So I though it could be overloading the circuit but this happens with the PC off. I have turned other plugs off within the same room and I still get the issue. However with the PC switched off at the wall, there has so far never been an issue.

When the power trips the smart plug defaults to off and this is why I initially did not see the fault for some days or even weeks. However, the PC can also be powered or at least plugged in for days withouth issue. I tried plugging into another non-smart plug socket to see if this solved it. It didn't. I replaced the PSU in the PC as I thought this was the only likely thing to cause it. It ran fine for a few days but unfortunately the problem has reoccurred and continues to do so.

It does trip the main trip (rather than the individual one for that circuit) which is a Hager CD284U.

Anyone have any clue what could be going on here?

Thanks a lot!
 
Instyle LED Lighting Specialists UK
This official sponsor may provide discounts for members
Advertisement - Content continues below

Spoon

-
Mentor
Arms
Esteemed
It does trip the main trip (rather than the individual one for that circuit) which is a Hager CD284U.
Welcome to the forum mate.
The above device is a RCD which detects earth leakage. It is not tripping the breaker so there is no current overload.
Do you just have the 1 RCD in your consumer unit? It sounds like you do.
If you have lots of chargers plugged in at the same time the these might just tip the balance of the RCD and make it trip.
You would try to see if you can fix the issue yourself, by removing all unused chargers from the sockets.
Another option is to get an electrician round who could test the circuits and see which is causing the problems.

If you could, please post a pic of your CU showing the breakers & RCD.
 

James

-
Mentor
Arms
Supporter
Esteemed
This is sounding suspiciously like a neutral to earth fault somewhere.
Check outside lights for signs of water ingress
Same for any outdoor sockets

Any evidence of mice, they have been known to cause this sort of fault by chewing the insulation off a cable that can become damp.

Immersion heaters can cause a similar fault but normally they destroy themselves internally after a short time if water has got in and they will trip constantly.

Once you have checked the basics, if you have not found anything obvious, I would suggest you get an electrician in who is good at fault finding.

Insulation resistance checking should be able to narrow down the fault to a particular circuit.
 
  • Thread Starter Thread Starter
  • #4
Hi

Thanks for the warm welcome!

Glad to hear it isn't overloading. I do have just the one RCD by the looks of things.

I probably do have a more than average amount of things plugged in however it doesn't seem to matter how many items I have plugged in at once as long as this particular computer is turned off at the wall. Like I mentioned, it doesn't have to be even on, just turned on at the plug.

There is only the computer plugged into this socket. I do have sockets with many other appliances in the same room. However with all of these on and the computer turned off at the socket, no problem. Computer on, or just on at the plug, and all other plugs turned off, the issue can and will most likely occur.

I am clearly not an electrician but in my basic understanding I would question if it were anything else - i.e chargers, immersion heaters, outside lights etc etc, where would the relevance of the PC being plugged in come into play? And would this issue not occur whether this PC was present or not?

One thing I wondered is if maybe it could be one of the many USB devices plugged into the computer and maybe the fact that these ports could be "live" without the computer actually being on but still plugged in. Having scoured Google, I can't seem to find any reference to this happening though. Could a USB device cause these RCDs to trip?

The majority of times I have seen the power go off is when the saniflo kicks in and maybe this is the real culprit but it still seems extremely strange to me that it never causes a problem without the computer being in the mix!

I have requested an electricican come out to inspect next week but of course, if I could find the fault before hand then it would be ideal!

Thanks again.

IMG_9474.jpg
 

Spoon

-
Mentor
Arms
Esteemed
One thing I wondered is if maybe it could be one of the many USB devices plugged into the computer and maybe the fact that these ports could be "live" without the computer actually being on but still plugged in. Having scoured Google, I can't seem to find any reference to this happening though. Could a USB device cause these RCDs to trip?
None of the USB sockets should be live if the computer is switched off.

The majority of times I have seen the power go off is when the saniflo kicks in and maybe this is the real culprit but it still seems extremely strange to me that it never causes a problem without the computer being in the mix!
As a test, if you can switch off the saniflo then do so and put the computer on for the day. See if it trips then.
 
  • Thread Starter Thread Starter
  • #6
It actually just happened when I switched the oven on. So I don’t think it is saniflo related but more like when something that is using a higher amount of power.
 

James

-
Mentor
Arms
Supporter
Esteemed
It actually just happened when I switched the oven on. So I don’t think it is saniflo related but more like when something that is using a higher amount of power.
Without going in to technical details, there are some types of fault that will only show themselves when higher loads are applied to the circuit or other circuits on the same rcd.

I seem to remember a similar one with a kettle that was assumed faulty but it was in fact something else entirely.

Like I said, the fault is likely to be elsewhere, likely suspects are anything outside such as lights, pond pumps, sockets etc.
 
Advertisement - Content continues below

Reply to RCD Tripping Randomly When PC Plugged In in the DIY Electrical Forum area at ElectriciansForums.net

Wetroom Store - Network Wetroom Suppliers
This official sponsor may provide discounts for members
Advertisement - Content continues below
Top Bottom