National Homebrew Club Ireland

Brewing Discussions => Equipment & Chemicals => Topic started by: Jacob on January 02, 2014, 10:17:25 AM

Title: Immersion heaters - electrician advice needed
Post by: Jacob on January 02, 2014, 10:17:25 AM
Going to convert my brewery to electric soon but not sure how safe is it?

The plan is to use following:
MT - 2x 2.5kW, HLT - 2x 2.5 kW, pump ...

Can I plug it all to one socket on extension cable? :P



Title: Re: Immersion heaters - electrician advice needed
Post by: Will_D on January 02, 2014, 10:50:32 AM
NO!

An extension cable plug will have a 13 amp fuse.

A 2.5 kW heater will pull 10 Amps ( Amps = Watt / Voltage approx then is 1000/250 )

If you plug in two on a lead it may work for a short time but everything will get plenty hot.

So you decide to use 4 extension leads?

Next problem is where to plug them. Not into the same room!

The sockets are also protected by fuses or mini-circuit breakers. It then depends on if the sockets are off a radial or spur design.

A true ring main will be fused at 30 amps. Radials to to be at 20 Amps

You need to check how many socket circuits are in your house and what capacity they are.

You should find at least 3: Upstairs, Downstairs and Kitchen

So as a minimum you have 3 sockets.

Hope this helps Jacob. This is why most people get a sparks in to wire the brewery up with a separate fuse board and sockets designed to take the load.

Title: Re: Immersion heaters - electrician advice needed
Post by: brenmurph on January 02, 2014, 11:07:28 AM
good man will, lots to think about there.

Im in the middle of a complete revamp on the house. The electrictian was here before christmas going room to room.

When I suggested what I wanted in the brewery he recomended at least 4mmsq armoured cable ( much higher capacity)  which is equal to about a 6mmsq T&E ( standard cable) and suggested it should be on a 30 amp supply feeding 2 sockets for my two proposed 2.5 kw boilers.

There a lot to consider when loading up a socket with 30 amps ( keeping in mind lads and lassies that a 13 amp socket/ line may take 13- 30 amps(maybe up to 30 amps b4 tripping quickly) for quite a while with just a small overload).  if your cabling is in good nik all should be well as the cable is designed to tak e temperature up to a point, but if you have a very old house with a broken ring circuit then the ring cables could be well overloaded already so dont push it.

If your doin  brewwery pay the 30 quid ( standard labour 1-hr) and get the electrician to assess your supply and make recomendations.
In the meantime use one boilder on a circuit and run an extension cable ( fully unwound) to feed the other boiler from a different part of the house.
And if in dought about your fuseboard safety you can get a portable RCD just to be sure, which I recomend if u dont know that your fuseboard protectors are up to spec and functioning
Title: Re: Immersion heaters - electrician advice needed
Post by: Jacob on January 02, 2014, 11:30:15 AM
:( That's exactly what I was afraid of. Looks like I wont be able to convert to electric any time soon.
Not going to fix installation in the rented house just to get my keggle working.
Title: Re: Immersion heaters - electrician advice needed
Post by: Will_D on January 02, 2014, 12:39:12 PM
Just use 3 extensions as I suggested and you prolly will be OK.

Worstcase is a 13 amp fuse will blow or a plug/socket may get warm. Also always uncoil an extension lead if you are going to pull max current.
Title: Re: Immersion heaters - electrician advice needed
Post by: brenmurph on January 02, 2014, 12:53:36 PM
! am open to correction on any of this, however my recent experience bringing my centuryold house into the current standards offered me  numerous valuable insights:

The design of a household electrical installation is really aimed at having numerous sockets supplying radios,  mobile chargers and so on so there could be 10 sockets in a room each in theory capable of 13 amps but not several together.

The kitchen would have a seperate high capacity supply for say a cooker, as would a bathroom supplying showers, or a garage extension,  which would be equivalent to what we need in an electric brewery.
Therefore having 2 boilers is just a little more than one electric socket supply is aimed at. I stand corrected but from my research a standard cable (2.5mm T&E) supplying a socket is capable of 30 amps maximum (in free air) while in walls and where many cables run together this reduces/scales right down to 18.5 amps. 18.5 amps CANNOT take two boilers safely. Therefore, 2 scenarios.

Scenario 1. Electrical installation in your house is modern and works properly
The cable will tale the overload safely untill the tripper dis-engages

Scenario 2. The electrical installation is not up to standard, has had improper modifications, has had an original ring circuit damaged or  unringed. The cable will NOT take the overload before the tripper dis-engages and the risult is the well- recognised 'cable fire risk'

My simple recomendation is:

never plug 2 x kettles, 2 x electric boilers  or 2 electric heaters or combination of any into one socket outlet.

For our many brewers using electric kettles this is an issue. Boiling a kettle for a cup of tea is not an issue however having a brew kettle boiling for 90 minutes gives the cables plenty time to overheat


Really the only simple safe solution is 2 x quality extension leads ( fully unwound) taking one from an upstaire socket and one from downstairs).
Title: Re: Immersion heaters - electrician advice needed
Post by: Ciderhead on January 02, 2014, 06:47:04 PM
I'm sure JD will weigh in here.
But get away with running a 2.2Kw on full blast on one socket and the other 2.2Kw on 50-75% depending how cold it is on the same ring main but different sockets.
She can't run the tumble drier but I have 2 fridges a 200W heat bulb and a freezer also running on the same ring at the same time.
Probably just as well all that lots in the garage!
Title: Re: Immersion heaters - electrician advice needed
Post by: brenmurph on January 02, 2014, 07:00:05 PM
@ tube

they also discovered that if for example if the ring broke, the house now has a 30 amp circuit on a 2.5.. cable.... dangerous. so run 2 x boilers will work till the wires go on fire
Title: Re: Immersion heaters - electrician advice needed
Post by: brenmurph on January 02, 2014, 07:24:34 PM
the upgrade on an older house like ,mine is to change the 32 a ring tripper with 20a to ensure safety. :)
Title: Re: Immersion heaters - electrician advice needed
Post by: Jacob on January 02, 2014, 07:41:21 PM
Ok, here are pics of my fuse box

https://www.dropbox.com/s/7xofro9kl95f67r/IMG_20140102_193554.jpg (https://www.dropbox.com/s/7xofro9kl95f67r/IMG_20140102_193554.jpg)
https://www.dropbox.com/s/bxm8iru1hlfdwbx/IMG_20140102_193600.jpg (https://www.dropbox.com/s/bxm8iru1hlfdwbx/IMG_20140102_193600.jpg)

Good, bad? :)
Title: Re: Immersion heaters - electrician advice needed
Post by: brenmurph on January 02, 2014, 07:47:48 PM
theres only one 32 a which is prob goin to kitchen or shower

ur row of 20a trippers suggests ( but im not an electrician) that your prob not on ring main rather the more modern.

In ur case it looks like ( but im not an electrician) all your sockets are protected with 20a mcb (tripper) which means all should be safe.

If you use 2 x 2.5kw boilers on a double outlet it is likely that it will go for a while and then just trip out.

Title: Re: Immersion heaters - electrician advice needed
Post by: Jacob on January 02, 2014, 07:55:41 PM
Yep, all sockets are on B20 and cooker is on B32.

Quote from: brenmurph on January 02, 2014, 07:47:48 PM
If you use 2 x 2.5kw boilers on a double outlet it is likely that it will go for a while and then just trip out.
In other words, no good :/

Thanks for the info lads!
Title: Re: Immersion heaters - electrician advice needed
Post by: DEMPSEY on January 02, 2014, 08:00:27 PM
You can always add another 32 to the fuse box and get it spurred to a socket then have a heavy duty cable for plugging into that socket for brew day.
Title: Re: Immersion heaters - electrician advice needed
Post by: brenmurph on January 02, 2014, 08:09:21 PM
thats why as we said earlier the only way is to take power from  sockets that are on different circuits with an extension lead ( fully uncoiled)

you are fine then for 2 x boilers

but u cany use just one double socket for the lot :) :) ;)

dont worry ur brewing career is safe :)
Title: Re: Immersion heaters - electrician advice needed
Post by: Jacob on January 02, 2014, 08:42:52 PM
For the moment I'll stay with gas. Once I'll get my own place will prep all.
Title: Re: Immersion heaters - electrician advice needed
Post by: brenmurph on January 02, 2014, 08:48:31 PM
another happy customer :)
Title: Re: Immersion heaters - electrician advice needed
Post by: Jacob on January 02, 2014, 09:52:25 PM
Quote from: brenmurph on January 02, 2014, 08:48:31 PM
another happy customer :)
Not so happy, had some big plans for brewery updates.
Those will have to wait :(
Thanks again for all the info!
Title: Re: Immersion heaters - electrician advice needed
Post by: Will_D on January 03, 2014, 01:41:23 AM
Just think outside the box or in your case "Think next door neighbour". Have a nice word and drop the extension cables over the back wall.

When we first moved in to an old terraced house in Salford(think Coronation Street - that was only about 4 streets away - really) that had been disconnected a simple length of cable with a plug on each end and a friendly neighbour did the trick a treat!

It allowed us the lights and the power tools to do the rewire.

Just as well as the T&E was lead sheathed over rubber! Looked just like the modern(then) grey plastic T&E!
Title: Re: Immersion heaters - electrician advice needed
Post by: JD on January 06, 2014, 10:19:53 AM
Quote from: CH on January 02, 2014, 06:47:04 PM
I'm sure JD will weigh in here.

92Kg last time I looked. :)
Title: Re: Immersion heaters - electrician advice needed
Post by: JD on January 06, 2014, 10:43:18 AM

In my old setup I had one element in the HLT and two in the BK and none in the MLT. I used to brew 40L batches with this setup with only a little extra time needed to get things up to temperature. I insulated each vessel in a  number of layers of aluminized bubblewrap and each vessel had an insulated lid to keep the heat in.

My new system, when I eventually get around to completing it, will have two elements in the HLT to get the ball rolling a bit quicker, one in a heat exchanger pot for the HERMS and two in the kettle. With five elements I will only ever need to use power from two 13A sockets (each on a separate mains circuit). Why? Because I will only ever power a maximum of two elements at any one time. MY HLT will use both until strike temperature is reached. Then one of them will be switched to the HERMS pot until the mash is over. When sparging is completed, both will be switched to the kettle to finish it all out. Once the kettle is rolling, only one element is needed to keep it there. Power used by pumps, controllers, etc. can be ignored as insignificant in the overall calculations.

Switching can be as simple as disconnecting the leads and reconnecting to the other elements. Fancier systems based on relays could be set up too as long as a crossbar switching system is used (basically your'll need as many relays as you have elements times the number of sockets you plugin into).



Title: Immersion heaters - electrician advice needed
Post by: Ciderhead on January 06, 2014, 11:53:27 AM
Quote from: JD on January 06, 2014, 10:19:53 AM
Quote from: CH on January 02, 2014, 06:47:04 PM
I'm sure JD will weigh in here.

92Kg last time I looked. :)

Christmas pud? ;)
Title: Re: Immersion heaters - electrician advice needed
Post by: JD on January 06, 2014, 12:36:48 PM
Quote from: CH on January 06, 2014, 11:53:27 AM
Quote from: JD on January 06, 2014, 10:19:53 AM
Quote from: CH on January 02, 2014, 06:47:04 PM
I'm sure JD will weigh in here.

92Kg last time I looked. :)

Christmas pud? ;)

Last time I looked was before the pud.  :-X Sayin' no more