3 phase water heater

[Soulsurfer]

Quoting a 3 phase water heater, would you fit a 3 pole or 4 pole isolator at appliance end ?

 

[DPG]

What's the supply type? Daz

 

[Pete999]

Quoting a 3 phase water heater, would you fit a 3 pole or 4 pole isolator at appliance end ?

Is it TP or TP&N??

 

[Soulsurfer]

Hey Daz, just been down to see the site it's a 3 phase 100A TN-C-S mate. 18-27kW adjustable instantaneous water heater. @ max 27 setup 39A load

 

[Soulsurfer]

I'm thinking by means of OSG & regs that as its TNCS it only requires 3 pole isolation not switched neutrals in 5.11.

 

[Pete999]

Ref post 3 is it a balanced load heater?

 

[snowhead]

Ref post 3 is it a balanced load heater?

Late / Early N ??

 

[Simlec]

I would say seeing as it a 3phase water heater it will not require a neutral unless the controls need it.

 

[Soulsurfer]

Looking at the spec I'm thinking it does not require neutral as shows 3/PE on spec, it is a DEX 18-27 model top line of sheet, hope link works ? http://www.spatec.co.uk/files/Download/zipinlinedexanddbx.pdf

 

[Soulsurfer]

Sorry Pete, not 100% but I think so.

 

[Soulsurfer]

Sorry for my lack of knowledge on this but I haven't done much in the way of 3 phase except HVAC systems for years before going on my own and undertaking mostly domestic works due to time constraints & young family, school runs etc..

 

[Pete999]

Looking at the spec I'm thinking it does not require neutral as shows 3/PE on spec, it is a DEX 18-27 model top line of sheet, hope link works ? http://www.spatec.co.uk/files/Download/zipinlinedexanddbx.pdf

Looks like a 3 pole isolator controlling the heater already installed for you, or are they just saying it's all you need?

 

[Soulsurfer]

Think just need my cable from d/b to an isolator with 3 pole min 3mm contacts separation. You can lock it down to say 18 or 21 kW otherwise I need to buy a 40A triple pole MCB from lad in UK who had some for around £150 ! If they want it run at full 27kW that is. Old polestar d/b so was going to feed into a new enclosure encasing an RCD then out to isolator.

 

[Deleted member 9648]

Think just need my cable from d/b to an isolator with 3 pole min 3mm contacts separation. You can lock it down to say 18 or 21 kW otherwise I need to buy a 40A triple pole MCB from lad in UK who had some for around £150 ! If they want it run at full 27kW that is. Old polestar d/b so was going to feed into a new enclosure encasing an RCD then out to isolator.

Does it need an RCD and why don't you feed it from the existing DB?....Polestar MCB's are still obtainable

 

[Pete999]

Think just need my cable from d/b to an isolator with 3 pole min 3mm contacts separation. You can lock it down to say 18 or 21 kW otherwise I need to buy a 40A triple pole MCB from lad in UK who had some for around £150 ! If they want it run at full 27kW that is. Old polestar d/b so was going to feed into a new enclosure encasing an RCD then out to isolator.

Just googled polestar mcbs £99 for a 63 Amp think your guy is pulling a fast one (EBAY SORRY)

 

[Leesparkykent]

The manufacturers instructions say it should be on an rcd.

 

[snowhead]

It doesn't use Neutral, the control voltage is derived from 2 phases, so a 3 pole isolator is all that's required.

http://www.spatec.co.uk/files/Download/zipinlinedexanddbx.pdf

 

[Soulsurfer]

Thanks all of you, yes def needs an Rcd but lad on Facebook was saying had loads of obsolete breakers 40A TP for £140-£150 that's why as was at 39A / phase full stack

 

[davesparks]

Sorry for my lack of knowledge on this but I haven't done much in the way of 3 phase except HVAC systems for years before going on my own and undertaking mostly domestic works due to time constraints & young family, school runs etc..

Then keep out of things you aren't experienced until you've got some time working with someone who can teach you under your belt.

 

[davesparks]

Thanks all of you, yes def needs an Rcd but lad on Facebook was saying had loads of obsolete breakers 40A TP for £140-£150 that's why as was at 39A / phase full stack

Here's a tip, don't buy tat from people on Facebook. Buy your materials from a reputable wholesaler or similar if you want to actually have a warranty on the parts and for your insurance to actually cover you for the job.