Priority Switch Problems

Shefwedfan

Ok, I have a setup at the moment with two electric shower. Shower A and shower B. They are on a priority switch. So if Shower B was on and shower A was turned on then shower B would turn off till shower A finished


All good. Got a car charger about 3 years ago. This was installed as well. No problem. It would turn off as well once Shower A or Shower B was turned on


Last few months I have a problem. I can't seem to rectify. If I have car plugged in, doesn't even need to be charging. Shower B is not been used. If shower A is used then power is cut to shower B.


Check the switch board and nothing tripped, I need to pull the switch down and put back up and then bang shower goes again. This is just happening randomly and I have tried all combinations myself and nothing then 20 mins later I go in and its gone.

Asked electrician and he said could be charger cable so I swapped it and same problem.



He mentioned it could be high moisture in the bathroom with the shower????



Any idea? and why would it not fully trip down the switch but cut the power off??? Thanks

meercat

Shefwedfan wrote: »

Ok, I have a setup at the moment with two electric shower. Shower A and shower B. They are on a priority switch. So if Shower B was on and shower A was turned on then shower B would turn off till shower A finished


All good. Got a car charger about 3 years ago. This was installed as well. No problem. It would turn off as well once Shower A or Shower B was turned on


Last few months I have a problem. I can't seem to rectify. If I have car plugged in, doesn't even need to be charging. Shower B is not been used. If shower A is used then power is cut to shower B.


Check the switch board and nothing tripped, I need to pull the switch down and put back up and then bang shower goes again. This is just happening randomly and I have tried all combinations myself and nothing then 20 mins later I go in and its gone.

Asked electrician and he said could be charger cable so I swapped it and same problem.



He mentioned it could be high moisture in the bathroom with the shower????



Any idea? and why would it not fully trip down the switch but cut the power off??? Thanks

What switch exactly is tripping or what switch do you have to pull down to reset. Post a pic if possible. Sometimes the rcd on electric showers have to be replaced over time.

Shefwedfan

Picture attached

The writing with Shower 1 & Shower 2 was originally put on it prior to charger

The switch I have to flick is the one with the blue button on it.

meercat

That’s the rcd.
My advice is to get a rec to investigate

Shefwedfan

meercat wrote: »

That’s the rcd.
My advice is to get a rec to investigate

Had electrician in.....


He said they never break .....said it was condensation



I am just wondering what it might be?

meercat

Shefwedfan wrote: »

Had electrician in.....


He said they never break .....said it was condensation



I am just wondering what it might be?

I’ve replaced numerous rcd’s
If it’s condensation,where is it getting in and causing a trip.
You need a competent rec to come in and test

Bruthal

Shefwedfan wrote: »

Had electrician in.....


He said they never break

I sometimes wonder how humanity made it.

kramer1

They break all the time

Shefwedfan

meercat wrote: »

I’ve replaced numerous rcd’s
If it’s condensation,where is it getting in and causing a trip.
You need a competent rec to come in and test

He said condensation at the shower not at the trip switch

Sounds dodgy to me

meercat

Shefwedfan wrote: »

He said condensation at the shower not at the trip switch

Sounds dodgy to me

Did he do an insulation resistance test to confirm this or just a visual inspection. A notice of potential hazard should have been issued
Get a competent rec in as this is a safety device and should be functioning correctly

Shefwedfan

meercat wrote: »

Did he do an insulation resistance test to confirm this or just a visual inspection. A notice of potential hazard should have been issued
Get a competent rec in as this is a safety device and should be functioning correctly

Visual


It was strange because the switch is not tripping but it is still stopping power. It was happening every so often a few months ago...nothing has changed and now regular occurrence.



Based on that I took it that it was failing. The electrician was onsite for another installation so I threw him a few quid to look at it, said nothing was wrong. Had to be condensation in the shower or something which was bridging the electricity and that was causing it to short out....I thought the answer was suspect but he didnt end up charging anything so left it.....windows wide open, no condensation in bathroom and still same random issue


I have checked interior of shower, all the switch's to make sure nothing looking dodgy and all ok....so only thing I can think is the trip switch is failing

Will need to ring someone else :P

Sleeper12

Shefwedfan wrote:

He said they never break .....said it was condensation

As a shower repair company we have to replace dozens of RCBOs per year. Most seem very healthy but some can become over sensitive. You can put an electric shower in a steam room in a gym & it shouldn't suffer from the condensation. I have seen a shower needing the RCBO replaced three or even four times before everything settles down. I have seen a brand new RCBO trip on a shower & have to be replaced. The same RCBO could then work perfectly with another shower of the exact same make & model.

Sleeper12

Shefwedfan wrote:

Based on that I took it that it was failing. The electrician was onsite for another installation so I threw him a few quid to look at it, said nothing was wrong. Had to be condensation in the shower or something which was bridging the electricity and that was causing it to short out....I thought the answer was suspect but he didnt end up charging anything so left it.....windows wide open, no condensation in bathroom and still same random issue

What piece of equipment did he use to determine this?

Pay a good REC to replace the RCBO that is tripping. This should resolve the issue.

Xwebstar2

Sleeper12 wrote: »

As a shower repair company we have to replace dozens of RCBOs per year. Most seem very healthy but some can become over sensitive. You can put an electric shower in a steam room in a gym & it shouldn't suffer from the condensation. I have seen a shower needing the RCBO replaced three or even four times before everything settles down. I have seen a brand new RCBO trip on a shower & have to be replaced. The same RCBO could then work perfectly with another shower of the exact same make & model.

Sounds more like black magic than electrical work

I haven't seen massive numbers of faulty Rcbos over the years

Shefwedfan

Thanks guys, I was thinking it was the issue

Like last night I turned on everything I could to see if I could over the switch, showers and all going and it worked like it should do

Then in middle of night, no load and get up this morning and it’s tripped, now unless a f**ker of a ghost needed a shower I have nonidea

Bruthal

Xwebstar2 wrote: »

Sounds more like black magic than electrical work

I haven't seen massive numbers of faulty Rcbos over the years

Neither have I. That does not mean they do not go faulty.

Bruthal

Another thing with RCDs and water, in a sort of matter of interest type way, it certainly can cause trips. But it is nothing like the conductor most seem to think it is.

Here is a photo with meter set in the 2 amp scale, one probe on a socket phase, the other in a stream of water from a tap. Not a broken droplet spray such as with a shower, but a continuous unbroken stream.

6.8ma for the length of stream in this particular moment.

Sleeper12

Xwebstar2 wrote: »

Sounds more like black magic than electrical work

I haven't seen massive numbers of faulty Rcbos over the years

Why would you? You don't work on a thousand or more electric showers per year so I wouldn't expect you to come across massive amounts of them. We'd replace more pull cord switches in a year than most electricians would in a lifetime. I've an electrician that earns more than the average industrial wage just from the RCBO & pull cord switch work I hand him each week alone.

Xwebstar2

And there's thousands of homes out there with Rcbos and they'd be calling registered contractors to replace them, which they're not ime

It seems to me that you advocate Rcbo trial+error replacement as a quick fix to solve issues external to the shower

Pull-cord replacement is a major issue , no dispute there

Sleeper12

Xwebstar2 wrote:

And there's thousands of homes out there with Rcbos and they'd be calling registered contractors to replace them, which they're not ime

No homeowners rarely do this. They call in shower repair companies who determine the issue and replace the RCBO with success.

Xwebstar2 wrote:

It seems to me that you advocate Rcbo trial+error replacement as a quick fix to solve issues external to the shower

Not trial and error. General Rule of thumb in shower repair is if it trips instantly & every time then the issue is likely to be the shower. If it trips intermittently then the issue is most likely not the shower.

Xwebstar2 wrote:

Pull-cord replacement is a major issue , no dispute there

With respect, your attitude here is not unlike OPs electrician. He believes that an electric shower intermittently tripping definitely isn't a faulty RCBO. He actually suggested that an electric shower that's designed, tested and passed to operate in a bathroom, with not just steam but with water splashing on it, was tripping the RCBO (even when not in use) because there was steam in the bathroom. Because he hadn't come across faulty and over sensitive RCBOs before he believed that they don't exist. He'd rather believe the improbable than entertain the idea that the RCBO could be at fault. This sounded ridiculous, even to OP, who then started the thread to try get to the bottom of the problem.

Just because you never or rarely see over sensitive RCBOs doesn't mean that they don't exist. You limit your ability to successfully diagnose a problem if you automatically reject the most likely cause. I'd be pretty certain if OP reports back here when problem is solved that he has a faulty RCBO/priority sw switch

Xwebstar2

I've been called out to faulty showers and RCD/Rcbo trips for 20 years

Faulty Rcbos has never been a major issue

Sure, if you swop it out 3-4 times the problem may go away

Xwebstar2

I'd also dispute that homeowners are calling shower repair companies for Rcbo trips and rarely electricians

Sleeper12

Xwebstar2 wrote: »

I've been called out to faulty showers and RCD/Rcbo trips for 20 years

Faulty Rcbos has never been a major issue

Sure, if you swop it out 3-4 times the problem may go away

Well working on 1000 plus shower every year for 30 years I would expect to see faulty RCBS much more often then you do. The beauty with the RCBO is that isnt designed to be over sensitive rather than under sensitive

Xwebstar2 wrote: »

I'd also dispute that homeowners are calling shower repair companies for Rcbo trips and rarely electricians

Dispute all you want. Fact is shower breaks people call a shower repair company. How do you suppose we make a living doing nothing else but electric & power showers? How do we work on 1000 shower pr year & you get a handfull of shower calls?


You understand this is my specialty right? I work at this & only this all day everyday?





I'll leave you with whatever beliefs you want. I'm not going to keep replying to what is really tunnel vision.


Best advice for OP is to get a good REC in to investigate. I assume OP has learned a lesson with the sparks he called & wont be using him again. Fingers crossed OP will report back with the answer to the mystery

Shefwedfan

I know this has taken a life of it own

In reality I probably would have called a shower person only for the fact the electric car charger was on the same priority switch so I thought an electrician would be able to cover both. If the issue existed and it was only the shower I think Sleeper would be getting a shout :-)

Xwebstar2 I am open to all idea what might be causing the issue? as I said nobody was having a shower in the middle of the night and when I woke it was gone again. Plus it is tripping but the switch doesn't go down. So when you look at the board everything looks normal. Now even that alone suggest to me something is not right with the switch but I am no expert and woudl be grateful for any explanation......

Thanks everyone for the help.....

meercat

It’s time to get a competent rec in and do some proper testing. Ask for the test results and a certificate
I’d expect it to be a faulty rcbo as I’d agree with sleeper12 and I’ve replaced many over time.
Let us know how you get on.

Shefwedfan

meercat wrote: »

It’s time to get a competent rec in and do some proper testing. Ask for the test results and a certificate
I’d expect it to be a faulty rcbo as I’d agree with sleeper12 and I’ve replaced many over time.
Let us know how you get on.

Will do, my usual electrician in Aus so that’s why I used the other plonker, looking out to get a good one now

Xwebstar2

Sleeper12 wrote: »

Well working on 1000 plus shower every year for 30 years I would expect to see faulty RCBS much more often then you do. The beauty with the RCBO is that isnt designed to be over sensitive rather than under sensitive




Dispute all you want. Fact is shower breaks people call a shower repair company. How do you suppose we make a living doing nothing else but electric & power showers? How do we work on 1000 shower pr year & you get a handfull of shower calls?


You understand this is my specialty right? I work at this & only this all day everyday?





I'll leave you with whatever beliefs you want. I'm not going to keep replying to what is really tunnel vision.


Best advice for OP is to get a good REC in to investigate. I assume OP has learned a lesson with the sparks he called & wont be using him again. Fingers crossed OP will report back with the answer to the mystery

Are you actually testing when issues arise?

Ramp tests

IR tests

Leakage current

Or as I suspect merely swopping out RCBOs when intermittent issues arise?

meercat

Sleeper12 wrote: »

I've an electrician that earns more than the average industrial wage just from the RCBO & pull cord switch work I hand him each week alone.

Sleeper 12 uses a rec to do his electrical work for him .why would you suspect him to merely swap rcbo without testing them. If a rcbo is replaced then a Cert 2 needs to be issued along with test results.ive said in an earlier post that I’ve replaced numerous rcbo,do you suspect me from swapping without testing too?

Sleeper12

Xwebstar2 wrote:

Are you actually testing when issues arise?

Leave it. I can't talk reason to someone who believes that if they don't see something that it doesn't happen. Other posters have already stated that they come across plenty of faulty RCBOs yet because you don't come across them they don't exist. I'm not saying that you are wrong in your experience. It's just that your experience in shower repair is extremely limited compared to mine. I don't expect you to see large amounts of faulty RCBOs as you aren't working on large amounts of showers.

Time to move on. OP has gotten good advice from meercat about getting it all checked out by a good REC

Sleeper12

meercat wrote:

Sleeper 12 uses a rec to do his electrical work for him .

I have to. I'm a plumber by trade originally. I've never taken the cover of a fuse box in my life.

Xwebstar2

Sleeper12 wrote: »

What piece of equipment did he use to determine this?

Pay a good REC to replace the RCBO that is tripping. This should resolve the issue.

By the way I'm not disputing that Rcbos give trouble

My issue is with the blanket type of statement you're making above

2011

Xwebstar2 wrote: »

By the way I'm not disputing that Rcbos give trouble

My issue is with the blanket type of statement you're making above

I don’t think Sleeper has made a “blanket statement”. I believe that he is simply sharing his knowledge based on a wealth of experience in a particular area. I suspect that nobody else on this forum has dealt with half as many electrical shower issues as him.

I also see that he is fully compliant in terms of restricted work, he uses a REC when required.

Xwebstar2

Sleeper12 wrote: »

. I have seen a shower needing the RCBO replaced three or even four times before everything settles down. I have seen a brand new RCBO trip on a shower & have to be replaced. The same RCBO could then work perfectly with another shower of the exact same make & model.

This would suggest to me that the Rcbos are not being tested, merely replaced as a quick fix

How can an Rcbo possibly be needing to be replaced 4 times to "settle down?" if it is tested after replacement

2011

Xwebstar2 wrote: »

This would suggest to me that the Rcbos are not being tested, merely replaced as a quick fix

Wouldn’t you expect the REC to test the RCBOs?

Sleeper12

Modern elements don't really leak any more due to improvements in design. Modern Pumped electric showers have low voltage motors. The only part in the shower with earth connected to it is the element. If someone tells me over the phone that the shower is tripping intermittently I ask has anyone literally held the shower head over the shower running water over it. If the answer is no then I don't go out. I send a REC. I know that the issue is most likely to be the RCBO. Less often its the pull cord switch in this particular situation. It's even possible to be a damaged cable but almost always it is the RCBO. I know this without ever visiting the home. If I'm wrong I'd have to pay REC for wasted visit. This doesn't happen though.

Had a call from a lady in a council house two weeks ago. Shower was intermittently tripping. I said it's not the shower, it's likely to be the RCBO. She said no, the council sent out a REC & he already replaced the RCBO. I told her that he needs to change it again. He wouldn't come back because he put in a new RCBO so it has to be the shower. I sent my REC out to replace the new RCBO. Shower hasn't tripped since. It doesn't happen often but I don't lie when I say I've seen the RCBO needing replacing several times

Xwebstar2

Sleeper12 wrote: »

Modern elements don't really leak any more due to improvements in design. Modern Pumped electric showers have low voltage motors. The only part in the shower with earth connected to it is the element. If someone tells me over the phone that the shower is tripping intermittently I ask has anyone literally held the shower head over the shower running water over it. If the answer is no then I don't go out. I send a REC. I know that the issue is most likely to be the RCBO. Less often its the pull cord switch in this particular situation. It's even possible to be a damaged cable but almost always it is the RCBO. I know this without ever visiting the home. If I'm wrong I'd have to pay REC for wasted visit. This doesn't happen though.

Had a call from a lady in a council house two weeks ago. Shower was intermittently tripping. I said it's not the shower, it's likely to be the RCBO. She said no, the council sent out a REC & he already replaced the RCBO. I told her that he needs to change it again. He wouldn't come back because he put in a new RCBO so it has to be the shower. I sent my REC out to replace the new RCBO. Shower hasn't tripped since. It doesn't happen often but I don't lie when I say I've seen the RCBO needing replacing several times

Shower trips Rcbo

Council change Rcbo

Rcbo still tripping

Send your rec to replace Rcbo again

2011

Xwebstar2 wrote: »

Shower trips Rcbo

Council change Rcbo
REC does not bother testing replacement RCBO

Rcbo still tripping

Send your rec to replace Rcbo again
This replacement RCBO is ok

Perhaps what I added in bold is correct? It would be quite unlucky but it is possible.

Personally I have not seen many faulty RCBOs but I have come across them.

Xwebstar2

2011 wrote: »

Perhaps what I added in bold is correct? It would be quite unlucky but it is possible.

Personally I have not seen many faulty RCBOs but I have come across them.

Could be the case here

However this is not a standard methodology when troubleshooting

2011

Xwebstar2 wrote: »

Could be the case here

I would suspect so.

However this is not a standard methodology when troubleshooting

We don’t know what methodology Sleeper’s REC used.
Whatever he did it appears to have worked.
I think we should give him the benefit of doubt.

Sleeper12

Xwebstar2 wrote:

Send your rec to replace Rcbo again

And the shower repair company did what DCCs electrician couldn't or wouldn't do. DCCs electrician couldn't fix the problem because he had tunnel vision. He'd never come across a new faulty RCBO before. He blamed the shower, walked away and wouldn't come back. Because we see this problem very regularly we were able to fix it.

I deliberately didn't quote or tag you in my comment because this back & forward is going nowhere. You are flogging a dead horse here.

Risteard81

The fact is that it is very rare for the RCD to be at fault in spite of the many (spurious) claims.

Xwebstar2

Risteard81 wrote: »

The fact is that it is very rare for the RCD to be at fault in spite of the many (spurious) claims.

I'm investigating RCD issues for as long as I can remember, circa 30 yrs

I'm amazed to hear that a faulty Rcbo is the cause of the majority of intermittent faults

If this was the case RECs would need a constant supply of RCBOS and RCDs for replacement of same

Sleeper12

Risteard81 wrote:

The fact is that it is very rare for the RCD to be at fault in spite of the many (spurious) claims.

How many showers do you repair in a year that you base that statement on? How many showers in your life time?

Risteard81

Sleeper12 wrote: »

How many showers do you repair in a year that you base that statement on? How many showers in your life time?

I base the statement on fact and good engineering judgment.

It is of course possible for RCDs to fail, but it is the least probable outcome when diagnosing tripping.

Xwebstar2

Off the top of my head the majority of RCD/Rcbo issues ime

1) RCD not passing all trip tests when fitted new

2) " Stiction "from test button not being pressed or RCD not tripping at all

3) Overload, loose connections or rcd contacts causing burnout at RCD

4) misc wiring faults/issues downstream causing tripping

I'm not aware of this phenomenon of over-sensitive Rcbos requiring replacement in the majority of cases of intermittent faults.

Sleeper12

Risteard81 wrote:

It is of course possible for RCDs to fail, but it is the least probable outcome when diagnosing tripping.

With the shower ruled out due to it being intermittent tripping that leaves pull cord switch damaged cable or RCBO. Statistically it is much more likely to be the RCBO compared to the pull cord switch or damage cable. More times than not the pull cord switch will trip instantly.

Sleeper12

Xwebstar2 wrote:

I'm not aware of this phenomenon of over-sensitive Rcbos requiring replacement in the majority of cases of intermittent faults.

Other electricians here have already said that they come across them ofter enough. We're not all telling lies you know

Sleeper12

Off topic but something that I can't recall coming across before happened this morning.

Before we touch a shower we check live neutral voltage and live earth voltage. Often with power showers we'll find bad earth readings. Id almost never get a bad earth reading on an electric shower. This morning (first time ever for me as far as I remember) I got a L N of 239v making the 9kw shower closer to a 10kw but the Earth had a reading of one. I'm sure many here can tell me I don't get out enough & that this is common but I pretty sure I haven't seen such a reading on an electric shower before. Like the News of the world reporter "I made my excuses and left". It'll have to be made safe before I can return to it.

Xwebstar2

239v would be highly unusual

2011

I don't think that there is any benefit to keeping this thread open any longer, it is just going around in circles.

A few things to consider:

Many domestic electricians spend an entire career during which they work almost exclusively on wiring new installations. Assuming they are good at what they do then troubleshooting could be something they rarely have to do. All the equipment they install is new so is less prone to failure. Many industrial electricians could spend years without installing any RCDs or RCBOs.

Both of the above types of electrician may be highly skilled and very experienced but may never (or rarely) come across a faulty RCD or RCBO. I am in this game a long time and I can only remember 2 (off the top of my head).

I am going to guess that the above applies to both Xwebstar2 and Risteard81. If so they have probably dealt with less faulty showers in their entire career than Sleeper12 has dealt with in the last month. The obvious reluctance to put a number on how many tells its own story.

Then we have a poster that works in a business in which they only get a call if there is an issue with a shower, which seems to be around 1000 such calls a year. These units are (or should) only be fed from RCDs / RCBOs in every case this is in stark contrast with many of the circuits that most electricians work with. As shower units are becoming less and less prone to failure and are frequently fed from old ELCBs / RCDs /RCBOs it increases the likelihood of encountering faults with these devices. I would also imagine that many of these devices were not tested properly in the first place.

If anyone has anything new or constructive to add please PM me and I will unlock.

2011

If the OP would like to respond with how things worked out I’m sure we would all be very interested. Obviously the thread could be reopened.