The thing is the Acti9is designed for industrial & commercial loads, not domestic, so it is much more robust, mind it is not 100% 125A rated, it does have a diversity factor.
Reccomend me a CU please
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Hi ProDave,
There seems to be one hell of a load on the existing box, but presumably diversity will bring the max load to a reasonable level, ie within the capabilities of a Domestic CU.
Presumably the Live Busbar is holding up, even though it may at times be handling more than it should be.
If I was lobbying for some business, I would suggest one of my LiVE boxes, say 16-mod at 390mm wide x 252mm high, with 11 x Standard RCBOs (do B50 but not C50)
I would use a 125A Main Switch and double up on the Live Busbar, which would solve any overload there. I would configure the neutral bar as 2 separate ones, each fed from the Main Switch by 2 x 16mm Blue Neutral links, thereby splitting the neutral load and minimising the overheating.
I could do the lot for around £150.00 + VAT, but, to be honest, this is just a top-of-my-head idea, without a serious thought having gone into it, so it may be possible to shoot it down in flames. On the other hand, Dave, you may be looking for ideas outside the box, if you pardon the pun.
SBS Dave
There seems to be one hell of a load on the existing box, but presumably diversity will bring the max load to a reasonable level, ie within the capabilities of a Domestic CU.
Presumably the Live Busbar is holding up, even though it may at times be handling more than it should be.
If I was lobbying for some business, I would suggest one of my LiVE boxes, say 16-mod at 390mm wide x 252mm high, with 11 x Standard RCBOs (do B50 but not C50)
I would use a 125A Main Switch and double up on the Live Busbar, which would solve any overload there. I would configure the neutral bar as 2 separate ones, each fed from the Main Switch by 2 x 16mm Blue Neutral links, thereby splitting the neutral load and minimising the overheating.
I could do the lot for around £150.00 + VAT, but, to be honest, this is just a top-of-my-head idea, without a serious thought having gone into it, so it may be possible to shoot it down in flames. On the other hand, Dave, you may be looking for ideas outside the box, if you pardon the pun.
SBS Dave
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Thanks Dave, that's well worth considering.
I am sure a B50 would be okay for the electric boiler. It is after all just a 12KW resistive heating element, so there shouldn't be a high inrush current.
I would have to "over order" the selection of rcbo's as I am sure some are just completely wrong (the unlabelled ones that I honestly don't know what they actually feed yet) Would you do a sale or return to let me order a few extras and return the ones I don't end up needing?
I like the idea of a 125A incomer and doubled up busbar, and the split neutral arrangement.
I will put that to the customer as a possibility and if he is okay I will contact you to firm up a proposal.
Dave
I am sure a B50 would be okay for the electric boiler. It is after all just a 12KW resistive heating element, so there shouldn't be a high inrush current.
I would have to "over order" the selection of rcbo's as I am sure some are just completely wrong (the unlabelled ones that I honestly don't know what they actually feed yet) Would you do a sale or return to let me order a few extras and return the ones I don't end up needing?
I like the idea of a 125A incomer and doubled up busbar, and the split neutral arrangement.
I will put that to the customer as a possibility and if he is okay I will contact you to firm up a proposal.
Dave
Hi Dave,
No problem. I could ship what you think you might need and Invoice you what you use, after you send back what you don't need.
You don't have an Account with me, but I am happy to deal with you on an open Account on this job.
It would be best to communicate via e-mail, as I don't visit the Forum on a daily basis.
SBS Dave
[email protected]
No problem. I could ship what you think you might need and Invoice you what you use, after you send back what you don't need.
You don't have an Account with me, but I am happy to deal with you on an open Account on this job.
It would be best to communicate via e-mail, as I don't visit the Forum on a daily basis.
SBS Dave
[email protected]
Sharpend
"It Just Is"
I will just say, that's a great service once again from you Dave, it doesn't go unnoticed. :Applaud
I hadn't seen a 50A in your range Dave, which was why I didn't suggest your solution, sorry.
Going to have to re-aquaint myself.
I have the same sort of senario, although this is an office refurb & change of use to domestic abode...no gas everything lectrikery
They have spec'd:
relocate cu some 6 meters away from its current location & upgrade from the 2way unit currently in use that powers 1x20a radial & 1x6a lighting for a unit to power the new loads......
8kw of electric rads
12kw redring instantaneous water heater
13kw range
10.8kw Mira sports shower
1x 32a ring
1x 20a radial for saniflo/2x extractors/cooker hood
1x 6a lighting
Their plan was to just extend the supply (submain) from the switch fuse located in the shop at the front some 20 meters away......I took a look last night :| not an easy route as the front shop is in fact offset to the left of the rear office, so they share the centre wall but only the last 15" of it anything forward of that & I'm into the estate agents office next door............currently a mem 60amp SF with the sub being 16mm² T/E that is sandwiched between the old brick wall & a stud wall.
I haven't heard back yet after quoting
They have spec'd:
relocate cu some 6 meters away from its current location & upgrade from the 2way unit currently in use that powers 1x20a radial & 1x6a lighting for a unit to power the new loads......
8kw of electric rads
12kw redring instantaneous water heater
13kw range
10.8kw Mira sports shower
1x 32a ring
1x 20a radial for saniflo/2x extractors/cooker hood
1x 6a lighting
Their plan was to just extend the supply (submain) from the switch fuse located in the shop at the front some 20 meters away......I took a look last night :| not an easy route as the front shop is in fact offset to the left of the rear office, so they share the centre wall but only the last 15" of it anything forward of that & I'm into the estate agents office next door............currently a mem 60amp SF with the sub being 16mm² T/E that is sandwiched between the old brick wall & a stud wall.
I haven't heard back yet after quoting
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I have sent an email.
I asked in that email if you had thought of doing a doubled up neutral bar, and suggested one way I thought it may work. If you find a solution that would work it would be worth posting it here.
My gut feeling is that a single 50A load that's on for a long time frame is pushing the limits for anything that is intended as a domestic board.
I think for me it would have to be one of the two answers that has come up in the thread in various ways:
A) Fit a commericial type A board, such as schneider.
B) Use your preferred brand of consumer unit (such as SBS compact RCBO based board) and sit a separate switchfuse for the 12kw of water heating. At one time I would have suggested a wylex 160CM, as they have twin terminal screws, plus you can loop 25mm² tails in and out of the supply side so avoids henley blocks. However they have replaced it for Amd3 (why? - it was mainly metal anyway, plus the plastics in the standard range never did go all drippy when hot!) The replacement I think still features twin terminal screws but you cant loop in and out
I think for me it would have to be one of the two answers that has come up in the thread in various ways:
A) Fit a commericial type A board, such as schneider.
B) Use your preferred brand of consumer unit (such as SBS compact RCBO based board) and sit a separate switchfuse for the 12kw of water heating. At one time I would have suggested a wylex 160CM, as they have twin terminal screws, plus you can loop 25mm² tails in and out of the supply side so avoids henley blocks. However they have replaced it for Amd3 (why? - it was mainly metal anyway, plus the plastics in the standard range never did go all drippy when hot!) The replacement I think still features twin terminal screws but you cant loop in and out
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If I do adopt the SBS solution, as well as dual busbars, high current main switch etc, I would configure it so the 50A rcbo has a clear vacant space either side of it as well.
In another time and another place SW confirmed my views on the age old practice of putting the MCB’s in ascending order from the isolator.
Grouped together the heat from higher rated MCB’s s is going to influence the ones around it. Interspersing high/low current MCB’s is a far better method when it comes to heat dissipation.
Should traditional convention or sound logic prevail?
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The solution I am discussing wth Dave will have 3 spare ways, so I am thinking:
Main switch
space
50A for boiler
space
40A for cooker
space
40A for shower
rest of mcb's small / larger ratings intermixed.
that gets the two that are likely to draw big loads for a long time out in the open.
Main switch
space
50A for boiler
space
40A for cooker
space
40A for shower
rest of mcb's small / larger ratings intermixed.
that gets the two that are likely to draw big loads for a long time out in the open.
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That 12KW heater certainly sounds problematical .
The advice about placing a 50A breaker in space is sound .
I had a customer who said that every summer the lighting went off in a printer's warehouse , had loads of sparkies in but every summer was the same .
There were three plug-in lighting tracks with twin fluorescent fittings , switched via contactors . Three 16A MCBs in the contactor enclosure.....tracks pulling 16A each.
I concluded that the summer heat was pushing the breakers over the edge so seperated them on the dinrail , problem solved.
The advice about placing a 50A breaker in space is sound .
I had a customer who said that every summer the lighting went off in a printer's warehouse , had loads of sparkies in but every summer was the same .
There were three plug-in lighting tracks with twin fluorescent fittings , switched via contactors . Three 16A MCBs in the contactor enclosure.....tracks pulling 16A each.
I concluded that the summer heat was pushing the breakers over the edge so seperated them on the dinrail , problem solved.
Sharpend
"It Just Is"
Whilst it's a good idea, I'm always concerned that the leaving of space between heavy loaded mcbs is tempting fate in itself? If an additional circuit was to be added then the likely hood is that it will be a radial to a relatively high load, such as hot tub, garage/workshop? Which would then substabtially increase the problem you are eliminating?
Just thinking out loud................
Just thinking out loud................
maybe, but if this is one of dave's boards, then it wont simply be a case of fitting another breaker due to busbar design
Rob_the_rich
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Sharpend
"It Just Is"
Fair point, well made, but not impossible.
True, but would the average 5ww understand the importance?
Rob_the_rich
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Maybe, if other ways further along were labelled "spare", you can only do your best.
Edit; the label names would also be on the cert, so it would be documented
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