New Circuit

[soulman]

Hi,

I have a job to connect up a Single phase sunbed in a salon.  I have telephone the manufacturer for the spec of the sunbed.  They have told me I must use the following; 63A type c circuit breaker, 10mm cable into 63a rotary isolator & the circuit is to be protected by a 100ma rcd.  I have asked for these instruction to be e-mailed to me.  They said they do not give out exact spec's as they have a problem with electricians quoting much higher starting currents.  Also the 100ma rcd must be used & dont be tempted to put in a 30ma.

The DNO have installed a new meter especially for the sunbed.  100A fuse.  TNCS

I intend to do the following; from suppliers isolator 25mm tails into an 80a switched fuse.  Out of the switched fuse with 16mm 3 core swa for 16 meters to ccu.  I will earth the armour & also use the 3rd core as an earth.  I have used 63a as design current, the cable will be clipped direct which gives me 77Amps & volt drop of 2.41v.  (which I got from pages 334 & 335 of the brb).  I will go from the ccu with 16mm T&E straight into a rotary isolator.  Then connect the bed

Does the above sound o.k, have I missed anything. (be gentle)

Cheers

 

[steptoe]

Is that a sunbed!?

Or an actual artificial SUN!!!!?

Its must be a big one, Ive not seen one that large a load before,

 

[Andy™]

why do you need a cooker control unit, and where is the RCD?

 

[Blue Duck]

Good luck getting 10mm into a rotary isolator.

 

[Sidewinder]

Blue,

I've put 50 into a rotary isolator before now, you simply get one big enough for the cable, not the rated current!

 

[soulman]

Andy consumer control unit, & rcd is to go into consumer protecting the bed.  Blue duck can you suggest another isolator.

 

[soulman]

I am also concerned about the efli, which is 0.29 for 63a type c circuit breaker.  Any advice

 

[Evans Electric]

Is that a sunbed!?

Or an actual artificial SUN!!!!?

Its must be a big one, Ive not seen one that large a load before,

:slap :Applaud

Yep !  thats some sunbed  , get someone else to switch it on ...you get 1st degree burns from that!!!

 

[Sidewinder]

What's the Ze on the new supply?

 

[soulman]

Sidewinder, I haven't measured it yet, i only had a brief look as i was waiting for the manufacturers specification.

 

[Sidewinder]

Hi,

...

I intend to do the following; from suppliers isolator 25mm tails into an 80a switched fuse.  Out of the switched fuse with 16mm 3 core swa for 16 meters to ccu.  I will earth the armour & also use the 3rd core as an earth.  I have used 63a as design current, the cable will be clipped direct which gives me 77Amps & volt drop of 2.41v.  (which I got from pages 334 & 335 of the brb).  I will go from the ccu with 16mm T&E straight into a rotary isolator.  Then connect the bed

...

Cheers

So, as the cable can only carry 77A, I trust you are not fusing the sub main @ 80A?

 

[soulman]

Thank you sidewinder

 

[sparkytim]

Is this not a fixed load then? (See regs on OVERLOAD PROTECTION EXEMPTIONS).

FAULT current protection is ALWAYS required but NOT OVERLOAD protection if its a fixed Load.

So it is ok to have a CPD size in excess of the cable rating IF THE FIXED LOAD can not overload the cable. 

i.e  a 0.75mm pendant flex is protected by a 16 Amp MCB because the LOAD it will carry will never exceed the flex rating.

 

[ProDave]

63A  @ 230V = 14.49KW

Stand WELL clear when you turn it on. It's going to get HOT.

Please take a clamp meter with you and measure the ACTUAL current drawn when the sunbed is on.  I'm curious to see just how over rated the supply they are asking for really is.

Also please tell is what it says on the rating plate when you see it.

 

[Evans Electric]

Hi,

I have a job to connect up a Single phase sunbed in a salon.  I have telephone the manufacturer for the spec of the sunbed.  They have told me I must use the following; 63A type c circuit breaker, 10mm cable into 63a rotary isolator & the circuit is to be protected by a 100ma rcd.  I have asked for these instruction to be e-mailed to me.  They said they do not give out exact spec's as they have a problem with electricians quoting much higher starting currents.  Also the 100ma rcd must be used & dont be tempted to put in a 30ma.

The DNO have installed a new meter especially for the sunbed.  100A fuse.  TNCS

I intend to do the following; from suppliers isolator 25mm tails into an 80a switched fuse.  Out of the switched fuse with 16mm 3 core swa for 16 meters to ccu.  I will earth the armour & also use the 3rd core as an earth.  I have used 63a as design current, the cable will be clipped direct which gives me 77Amps & volt drop of 2.41v.  (which I got from pages 334 & 335 of the brb).  I will go from the ccu with 16mm T&E straight into a rotary isolator.  Then connect the bed

Does the above sound o.k, have I missed anything. (be gentle)

Cheers

I'd guess it will trip out at 30mA    .   How many prisoners...erm...customers do they cook in this thing at one go ?

 

[Sharpend]

Look we have 5ww courses the sun tan industry have the 1hour deep brown/red tan, keep up!

 

[Blue Duck]

Sidewinder... Sorry it wasn't a very constructive post, I was thinking of a job where a cheapie 63a iso was supplied for 10mm t&e, Thought ohh well, how hard can it be?!

Soulman try find one with a decent size enclosure

http://www.ebay.co.uk/itm/63A-30kw-4-POLE-ROTARY-ISOLATOR-SWITCH-IP65-SSRI-63A-/270623280575?pt=UK_BOI_Materials_Supplies_Electrical_ET&hash=item3f02678dbf 

Thinking about it that is one hell of a a sunbed!

 

[Jono Pashley]

AVOID Newlec Rotary isolators like the plague. They are a absolute nightmare to terminate cables into and earlier this year i had two faulty units back to back. IMO are my current prefered brand for Rotary Isolators.

 

[Andy™]

last 63a isolator i done i had no problem getting a 4c10 SWA in & out of it, so should be plenty space for a 10 / 16 T&E

 

[Bruspark]

There are indeed some pretty fierce "tan you in 10 minute" types about . . . this one has 48 225W tubes FFS

http://www.solansunbeds.co.uk/alisun-xxl.html

FWIW this supplier says say this about installation generally   (Hey don't shoot at me !!)

"Power requirements

Most people underestimate this, even some electricians if they haven’t installed a sunbed previously. As a

rough guide, a 200 Watt lamp uses about 1 Amp of electrical current, so a 40 tube 200 watt sunbed uses

around 40 Amps, which equates to 9.6 Kilowatts. This means that the cable supplying power from your

fuseboard to your sunbed room needs to be 10mm (size in cross sectional area) which is thicker than most

shower or cooker cables. A 60 tube sunshower needs 16mm cable. Its amazing how many people think

that the sunbed can be simply plugged in to a conventional socket! A 13 Amp plug has a maximum power

capability of 3 Kilowatts before the fuse will blow.

What’s more, a sunbed is what’s called an inductive load. This means that when it starts up, it draws around

10 –20% more current during the first few seconds, just like an electric motor. Many electricians do not realise

this, and although it does not affect the cable size required, it does affect the size of the circuit breaker (fuse)

in your fusebox. If the 40 tube (40 Amp) sunbed in the example above was supplied via a 45 Amp circuit

breaker, it would trip out on start up, giving the impression that the sunbed was faulty.

There are two solutions: one is the obvious, to fit the next size up circuit breaker. Unfortunately, this is either

50 Amps, or 63 Amps. The wiring regulation do not recommend a 63 Amp breaker to protect a 10mm cable,

as it results in a mismatch that can be potentially a fire hazard, so a 16mm cable would be required, which is

much more expensive, and cumbersome to route through your shop due to its larger physical size.

The other option is to use a Type “C” circuit breaker in the fuseboard. Electricians call these ‘motor start

breakers’ and these allow a higher initial start-up current to flow without tripping, as used on industrial electric

motors. Problem solved!

Leisure Centres and hotel chains may also insist on having what is known as an RCD, or Residual Current

Device fitted, also called RCB. This is similar to a circuit breaker and provides additional electric shock

protection to the sunbed user. Whilst this is not yet mandatory in the Wiring Regulations, larger companies

(and most suppliers of new commercial sunbeds) tend to insist on installing them to reduce the potential of

electrocution. In our current litigation-crazy society, this is likely to become more common in the future, and so

fittng a RCDis recommended"

Taken from http://www.solansunbeds.co.uk/How_to_Set_up_a_Successful_Tanning_Salonv1.2.pdf