Removing a relay

[boris1]

Thanks everyone for the advice. It was invaluable in diagnosing the situation.

The owner thought that the whole relay was broken and wanted to replace it. It turned out it was a broken 12 year-old Schneider Connect wireless switch. It was actually a different relay (the one next to it) that was controlled by the wireless switch. I guess the original electrician installed a relay because even though there were just a few of these lights, they were in different parts of the premises and were wired across three phases. If the original installed had just ran the wiring through one more wall (there was already a hole) he could have installed an ordinary wall switch.

How long do these Schneider Connect switches usually last? The owner wanted to spend as little money as possible, so I recommended replacing it with a NEXA wireless switch (the 433MHz one-way system) but even the 35€ was above their budget so we re-routed the relay to be controlled by a specific control circuit breaker. They only use these lights once a week and wanted to use the circuit breaker as a switch instead of wiring a regular/wireless wall switch.

The funniest part is they tried to turn the power on by sticking a pen/pencil into the I 0 part of the relay to try turning it on. After everything started shaking they took the pencil out and understood that that was a bad idea!

 

[timhoward]

The funniest part is they tried to turn the power on by sticking a pen/pencil into the I 0 part of the relay to try turning it on. After everything started shaking they took the pencil out and understood that that was a bad idea!

You now have me worried - is there no cover of any description over those terminals?
There's 400v sitting there!

 

[boris1]

You now have me worried - is there no cover of any description over those terminals?
There's 400v sitting there!

Well no, there are no covers, this is how it sits in the consumer unit. You can see some of the marks on the plastic from whatever they tried sticking in there. I told them not to do that anymore, ever.

 

[timhoward]

Well no, there are no covers, this is how it sits in the consumer unit. You can see some of the marks on the plastic from whatever they tried sticking in there. I told them not to do that anymore, ever.

I can't comment on the regs in Finland, but if that were here in the UK I wouldn't feel I could just walk away from that.

 

[boris1]

I can't comment on the regs in Finland, but if that were here in the UK I wouldn't feel I could just walk away from that.

What would you do? They are all like that: LC1K09 - Recherche Google - https://www.google.com/search?q=LC1K09&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ved=2ahUKEwji18On4uTwAhXjCRAIHa9BBvAQ_AUoAXoECAEQAw&biw=987&bih=689

This is the consumer unit, it’s out of reach of children and I think most people know not to mess around in there. If someone really wanted to, they could stick a fork/knife into the screws and get all those 400 volts. The screws are not covered either (just depressed when they are screwed in.

 

[DPG]

What would you do? They are all like that: LC1K09 - Recherche Google - https://www.google.com/search?q=LC1K09&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ved=2ahUKEwji18On4uTwAhXjCRAIHa9BBvAQ_AUoAXoECAEQAw&biw=987&bih=689

This is the consumer unit, it’s out of reach of children and I think most people know not to mess around in there. If someone really wanted to, they could stick a fork/knife into the screws and get all those 400 volts. The screws are not covered either (just depressed when they are screwed in.

'It's kind of out of reach'
'Most people know not to mess with it'

Not phrases I would expect to hear relating to 3 phase 400V equipment that people are using to switch some lights on and off!

 

[timhoward]

What would you do? They are all like that

This is the consumer unit, it’s out of reach of children and I think most people know not to mess around in there. If someone really wanted to, they could stick a fork/knife into the screws and get all those 400 volts. The screws are not covered either (just depressed when they are screwed in.

In terms of UK regulations "Basic Protection" is first on the list, and I'd be looking at moving the relays into an enclosure, or very carefully weighing up the requirements of using the "placing out of reach" method of basic protection, which probably wouldn't be appropriate in this case and is often hard to meet.

(I made the mistake 20 years ago of naively thinking that just because a consumer unit uses a DIN rail, anything designed for a DIN rail could go in it. In that it was case a contactor for storage heaters in a commercial workshop. It also poked out of the front, exposing live parts. I showed someone a photo of it, proud of my work, and got torn to shreds, and did 16th edition soon after)

Anyway, I'd be quite surprised if the current installation meets local requirements and unless you are 100% sure it is compliant I'd seek a second opinion.

 

[boris1]

In terms of UK regulations "Basic Protection" is first on the list, and I'd be looking at moving the relays into an enclosure, or very carefully weighing up the requirements of using the "placing out of reach" method of basic protection, which probably wouldn't be appropriate in this case and is often hard to meet.

(I made the mistake 20 years ago of naively thinking that just because a consumer unit uses a DIN rail, anything designed for a DIN rail could go in it. In that it was case a contactor for storage heaters in a commercial workshop. It also poked out of the front, exposing live parts. I showed someone a photo of it, proud of my work, and got torn to shreds, and did 16th edition soon after)

Anyway, I'd be quite surprised if the current installation meets local requirements and unless you are 100% sure it is compliant I'd seek a second opinion.

There may be a misunderstanding because I didn’t show the picture of the enclosure.
It has a lid like any other and they even added a lock to it. It passed the local regulations and has been installed like this for about 12 years (when that wireless Schneider Connect switch was implemented).
I don’t think anyone would go trying to switch a contractor indicator switch but I suppose it would be good to put that little switch and the screws behind some plastic covers. Hint to the electric manufacturers?

 

[DPG]

Ah, so there is a lid fitted which requires a screwdriver to open it? But how do they operate the MCB to switch the lights on and off?

 

[timhoward]

There may be a misunderstanding because I didn’t show the picture of the enclosure.

Yes, in my mind that is a "cover of any description" and considerably safer than I was fearing.