Panel Wire

[Scrappy042]

Afternoon guys,
Quick question, if I run out of panel wire (trirated), can I use the middle of a T&E cable as a temporary fix? E.g. Strip of grey outer sheath and use the brown/blue sheathed cable.

 

[stillp]

What's the panel? What are you doing to it? How 'temporary' is this fix?

 

[Scrappy042]

Panel is a simple home automation (HA) relay to a Volt-free relay to switch boiler on/off.
Temporary is a week or 2.

Boiler power feeds the HA relay, this then signals for the volt-free relay to switch NO for boiler to fire up.

Setup is ok and advised by HA company, but I've run out of panel wire and not free to get any for a week or 2. Figuring as its all below 5amp, the Live and Neutral of T&E obviously rated at 13amp might be sufficient for testing?

 

[stillp]

Should be OK for testing. It won't have the same temperature rating as tri-rated, but should be OK to operate a relay. Keep it clear of other conductors.

 

[Scrappy042]

Yeah. It's the temp I was worried about. I'll install and run for a bit to get some idea.
I assumed it would be alright as surely it can lose more heat of grey sheath is removed?

It will be in a standard din rail CU so casing isn't conductive and all other components are insulated as industry standard.

 

[Spark123]

I doubt it will be an issue like that permanently. Twin and earth has unsheathed conductors in a consumer unit anyway. What sort of temperature are you looking at, normal PVC is 70ºC max.

 

[Scrappy042]

Well it will be wall mounted (replacing the Hive controller) next to the gas boiler. Boiler exterior never gets hot (as you'd expect), slightly warm, would guess 20-ish degrees.
Air temp is around 20-25 as the expansion radiator is in the same room.

The volt-free relay is rather warm to the touch, but i'd expect that given its job. Cables aren't too close to that.

 

[Scrappy042]

4mm, 600v max tri-rated should be fine for this. 6mm seems a bit too much i think...

 

[Iggifer]

4mm, 600v max tri-rated should be fine for this. 6mm seems a bit too much i think...

for 5amps?

 

[EFLImpudence]

the Live and Neutral of T&E obviously rated at 13amp might be sufficient for testing?

1mm² is 16A

 

[JohnW2]

I think I must be missing something here. Are we not talking about 'wires' to a couple of relays which, in turn, switch a boiler on and off?

Kind Regards, John

 

[Spark123]

What current is in the wiring? I'm thinking you're going way over the top. A bit of 1mm is probably way bigger than needed.

 

[JohnW2]

What current is in the wiring? I'm thinking you're going way over the top. A bit of 1mm is probably way bigger than needed.

Exactly my point. ... and assuming that this counted as a "signalling and control circuit", then 0.5mm² would be allowed by BS7671.

Kind Regards, John

 

[EFLImpudence]

if I run out of panel wire (trirated), can I use the middle of a T&E cable as a temporary fix?

Yes.

 

[securespark]

if I run out of panel wire (trirated), can I use the middle of a T&E cable as a temporary fix?

Only if you do a special dance and swear allegiance to the cable fairy.