Removing a relay

[boris1]

I'm trying to learn more about relays.
Can someone link to a resource that describes how they work? I mean like a wiring diagram of 1L1 3L2 5L3 2T1 4T2 6T3...
Here is a LC1K09 that is connected to a lighting circuit.
What are the alternative ways to remove/disconnect it and instead have the switching done manually?
By manually I mean either with a circuit breaker or wall switch.

 

[boris1]

I'm trying to learn more about relays.
Can someone link to a resource that describes how they work? I mean like a wiring diagram of 1L1 3L2 5L3 2T1 4T2 6T3...
Here is a LC1K09 that is connected to a lighting circuit.
What are the alternative ways to remove/disconnect it and instead have the switching done manually?
By manually I mean either with a circuit breaker or wall switch.View attachment 85987

According to this:

Wiring Diagram For Schneider Contactor

Wiring diagrams help technicians to see how the controls are wired to the system. Fr a820 04750 fr a840 00023 fr a842 12120 fr a846 00023 f...

wiringdiagramall.blogspot.com

I could theoretically connect an independent switch to A1/A2 and have the lights controlled manually that way?

 

[westward10]

1L1, 3L2 and 5L3 correspond to 2T1, 4T2 and 6T3 respectively so 1L1 switches to 2T1. A1 and A2 are the coil connections which energise the relay by way if a coil, apply voltage to them and the switch closes. 13NO and 14NO are auxiliary contacts normally used as part of the control circuit, NO meaning they are Normally Open when the relay is not energised.

 

[westward10]

According to this:

Wiring Diagram For Schneider Contactor

Wiring diagrams help technicians to see how the controls are wired to the system. Fr a820 04750 fr a840 00023 fr a842 12120 fr a846 00023 f...

wiringdiagramall.blogspot.com

I could theoretically connect an independent switch to A1/A2 and have the lights controlled manually that way?

Yes you can providing the coil and your switch voltage are compatible. You also need to consider if the auxiliary contacts are being used although a manual switch is likely to override this but again you need to know the voltage of the control circuit.

 

[westward10]

I assume this follows on from your other thread. I see you are a trainee and if this is a work situation are your superiors not able to give you some guidance.

What are these relays in the fuse box?

Hello, can someone explain to me what these are and how they work? I suspect these are relays that control the electro heaters because the heating dials have an On and Night setting. Or because there is a dial in another part of the house where I assume some kind of schedule can be programmed...

www.electriciansforums.net

 

[boris1]

1L1, 3L2 and 5L3 correspond to 2T1, 4T2 and 6T3 respectively so 1L1 switches to 2T1. A1 and A2 are the coil connections which energise the relay by way if a coil, apply voltage to them and the switch closes. 13NO and 14NO are auxiliary contacts normally used as part of the control circuit, NO meaning they are Normally Open when the relay is not energised.

Thanks, I understand the L & T switching. Thanks for explaining the NO and A. I'll measure the voltage on A. I don't understand Finnish so well and my superiors like to have their weekends undisturbed. I just want to learn more on my own in English and to be more independent.
I would like to simplify this and am wondering if removing this relay entirely (or one of the three circuits) and replacing it with a switch/breaker would be foolish or wise.

 

[telectrix]

the purpose of a relay or contactor is to power a load which is greater than the capacity of the switch and/or it's associated circuitry. also to be able to control the relay /contactor using a lower/safer voltage to energise it, and with a multipole contactor, yo can use 1 switch to switch 2/3/ separate circuits.

 

[boris1]

the purpose of a relay or contactor is to power a load which is greater than the capacity of the switch and/or it's associated circuitry. also to be able to control the relay /contactor using a lower/safer voltage to energise it, and with a multipole contactor, yo can use 1 switch to switch 2/3/ separate circuits.

Thank you for explaining, that makes sense. What doesn't make sense is if there are three phases for "cleaning lights". I haven't visited yet and only have this photo from the customer. I assume it's only a lighting circuit so should be 10A (maybe 16 amps if there's something extraordinary going on). If that's the case, or even 16A, then a simple switch should do.
Is it safe to assume that one of these three circuits can be disconnected from the relay and the other two will remain functioning as before?

 

[westward10]

Thank you for explaining, that makes sense. What doesn't make sense is if there are three phases for "cleaning lights". I haven't visited yet and only have this photo from the customer. I assume it's only a lighting circuit so should be 10A (maybe 16 amps if there's something extraordinary going on). If that's the case, or even 16A, then a simple switch should do.
Is it safe to assume that one of these three circuits can be disconnected from the relay and the other two will remain functioning as before?

May be may be not. It is not uncommon for lighting circuits across three different phases to share a neutral provided they are protected by way of a triple-pole linked device, but this would be for the UK. They other two would remain functional but in my example disconnecting the outgoing conductor from the relay will leave a live conductor. It all depends on how the three are connected.

 

[timhoward]

My sixth sense is saying that someone went to the extra trouble of designing it with a relay for a reason in the first place. It might be to use a single switch for 3 higher current loads as Tel said. It might also be to allow automation e.g. a time clock etc.
The size of the conductors used might be a further clue, of course as well as looking at the current draw of whatever it is switching. Basically it comes down to understanding what it is switching.

 

[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.