rotary isolator

[Jackflash]

When an air con installer asked for a 25A isolator are they expecting a 20A or 32A supply to it?

 

[Plonker 3]

Why didnt you ask when you asked for the spec of the isolator?

The size of supply is dependant on the load not on the size of isolator fitted.

 

[telectrix]

what he said. ^^^^^. also, i'd not expect to see a 25A isolator with a 32A load,...unless it was on a farm. :uhoh2:

 

[Jackflash]

Yes you are correct Dillb, in an ideal world i would have totally asked that and they would have given me the answer but all they ever know is that they need a 25A isolator.

 

[Jackflash]

Is it because they don't produce a 20A rotary isolator?

 

[Plonker 3]

As its AC on a dedicated circuit Iwould expect overload isnt a problem so you could have 25 amp isolaotor and 32amp MCB.

 

[Plonker 3]

Yes you are correct Dillb, in an ideal world i would have totally asked that and they would have given me the answer but all they ever know is that they need a 25A isolator.

When you go to survey the job look ar what the Ib Is of the AC unit and install accordingly

 

[Jackflash]

When you go to survey the job look ar what the Ib Is of the AC unit and install accordingly

I would have but the unit is not installed yet

 

[Plonker 3]

Well seeing as you can do nothing before obtaining the Ib you are pretty much stuffed on everything then aren't you.

 

[Jackflash]

Well seeing as you can do nothing before obtaining the Ib you are pretty much stuffed on everything then aren't you.

Hahahah ok thanks, i guess i'l have to try and get in contact with them and press harder for the information needed. Just wanted to know if anyone else comes across this situation as much as me. Thanks for your help.

I think they think they're being helpful specifying the isolator as opposed to the Ib but it's really annoying.

 

[Octopus]

Is it because they don't produce a 20A rotary isolator?

Hum..... 20A, 32A

Know which one I would fit!

 

[Jackflash]

IP65 Isolator Switch 25A | Control & Pushbutton Stations | NoLinkingToThis

@murdoch ……. you do?

 

[Octopus]

IP65 Isolator Switch 25A | Control & Pushbutton Stations | NoLinkingToThis

@murdoch ……. you do?

That would depend on the load on the end of the circuit, the cable and the OCPD. My design "instinct" would be to install 32A


What is the spec of the load?

 

[123]

When an air con installer asked for a 25A isolator are they expecting a 20A or 32A supply to it?

Why not give them a 25A supply?

 

[Jackflash]

Why not give them a 25A supply?

Have you ever bought a Hager 25A mcb? Are they produced?

 

[Plonker 3]

What like one of these?

Hager MCB 25 Amp Single Pole Circuit Breaker Type B 25A B25 462125 NB125 | eBay

 

[Jackflash]

What like one of these?

Hager MCB 25 Amp Single Pole Circuit Breaker Type B 25A B25 462125 NB125 | eBay

No way!!!!!!!!

 

[Octopus]

So are you going to run in the supply using 2.5mm or 4mm cable?

 

[Plonker 3]

So are you going to run in the supply using 2.5mm or 4mm cable?

Without the design current he can not calculate anything yet.

 

[Jackflash]

So are you going to run in the supply using 2.5mm or 4mm cable?

…….Might see if i can get some 3.5mm.

But seriously its a bit of a run so it's going to be 4mm SWA.

I still can't get over their 25A mcb business, Are they commonly stocked?

 

[Plonker 3]

Well a internet search engine thinks so. maybe you need a new wholesaler

https://www.google.co.uk/webhp?sour...25GB625&ion=1&espv=2&ie=UTF-8#q=hager 25a mcb

 

[davesparks]

…….Might see if i can get some 3.5mm.

But seriously its a bit of a run so it's going to be 4mm SWA.

I still can't get over their 25A mcb business, Are they commonly stocked?

Will 4mm be big enough if it is a bit of a run?

What is there to get over? Most decent manufacturers offer a 25A mcb

 

[123]

Have you ever bought a Hager 25A mcb? Are they produced?

Yes!
Also recall having to buy 1A MCB's before. IIRC Hager make 0.5 MCB's as well

 

[Jackflash]

Well a internet search engine thinks so. maybe you need a new wholesaler

https://www.google.co.uk/webhp?sour...25GB625&ion=1&espv=2&ie=UTF-8#q=hager 25a mcb

Yea i checked out 'tlc' and a couple of other online shops which only displayed the 'standard' rated mcbs. I can't think I've ever come across a 25A mcb. Perhaps it's the 'go to' mcb for air con units!

 

[Plonker 3]

Yea i checked out 'tlc' and a couple of other online shops which only displayed the 'standard' rated mcbs. I can't think I've ever come across a 25A mcb. Perhaps it's the 'go to' mcb for air con units!

That depends on the size of AC units, I have been wiring quite a few up recently that are rated at 12 amps.

 

[Jackflash]

Will 4mm be big enough if it is a bit of a run?

What is there to get over? Most decent manufacturers offer a 25A mcb

yea 4mm is plenty, thats why i say its a bit of a run and not a hell of a run. I will be checking appendix F though.

yea 25A mcb makes total sense now, thanks

 

[Jackflash]

That depends on the size of AC units, I have been wiring quite a few up recently that are rated at 12 amps.

Yes of course, thanks

 

[Octopus]

…….Might see if i can get some 3.5mm.

But seriously its a bit of a run so it's going to be 4mm SWA.

I still can't get over their 25A mcb business, Are they commonly stocked?

Just stick a 32A one in if the load and cable are OK.

Just saying!

 

[uksparks]

Here's a 40A isolator i fitted today when I put a 32A circuit in for the hot tub.

 

[davesparks]

Surely that's not SY cable installed outdoors?