3 phase conundrum

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Awful those Proteus hex terminals, the last ones I had to fit were in a load of 100a blocks (which I later took out and replaced) the 3mm hex ranged from 3mm to about 3.4mm so an allen key only fit some of the screws, the larger holes it just spun round! I had to bash in a torx screwdriver to get them to turn. The heads were all wonky and misshapen, total rubbish.
 
If there are 2 MCBs (one in the 3 phase board and one in the smaller CU for the individual circuit), when a fault occurs it's anyone's guess as to which one will disconnect. Perhaps it will be the one in the CU so only a single circuit is disconnected. Or the main one in which case the entire CU has been disconnected because of a single fault.
………….. but if the TP board has a 63 amp and the CU a 50 (electric shower - and the max I'm ever likely to need), then won't the CU go first and leave the TP alone?

PatsPatter
 
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WPD fit Proteus DP Isolators too. The ones with the stupid 3mm Allen key terminals. Why 3mm? Snappy snap snap.

Bet they're a boat-load cheaper than Wylex

Wishing you were installing Wylex instead says heaps about Proteus!!
 
Awful those Proteus hex terminals, the last ones I had to fit were in a load of 100a blocks (which I later took out and replaced) the 3mm hex ranged from 3mm to about 3.4mm so an allen key only fit some of the screws, the larger holes it just spun round! I had to bash in a torx screwdriver to get them to turn. The heads were all wonky and misshapen, total rubbish.
Ah ha!! Mechanical. Nearer my skillset. Might I suggest trying a backup of an old fashioned, imperial 1/8" allen key.
It's actually 3.17mm and might just make all the difference and save you digging about for a torx bit and bashing it in. If you do try it, gently grind the ends of the hex to remove any radiusing on the flats and make sure there are no burrs left. The radius is only there to make fitting it to a well-sized socket easier - and prevent you removing bits of flesh. ;)

PatsPatter
 
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If you shop around well enough, you can pick up schnieder RCBOs for MUCH less than the list price.

eBay is great, if you're careful. Only go for new ones, ………………...

Make sure if you go that route to only buy the new style (with the curved white is test button around the toggle) or the old style (with a grey test button under the toggle) it'll look proper gash if you mix the two

Got that, ta.
As you say a quick look at fleabay brings up lots - both this (older?) type:

Older.jpg


….and this (newer?) type:
Newer.jpg


As you say, it'll look pretty gash with them mixed…………….. and I've already got plenty of that in stock :(

PatsPatter
 
Go with the newer ones. I'm not 100% sure the older multi9 breakers and RCBOs properly fit the new acti9 boards.
 
Have not tried old Rcbos in the new Acti 9 boards.
Due to the fact, the old style are obsolete, we do have problems fitting the new rcbo,s in the older boards, mainly they dont seem to clip in right, though occasionally do fit.
physically the fitting looks identical, so it seems odd, we recently reused the mcbs in a damaged board and the old style mcbs fitted the new board fine, the issue seems only with the rcbos.
So yes I would agree that its possible you could have rcbo problems
As per others id get the latest cream colour ones so all looks neat
Also , im not sure you intended to, that them ones in the pic fit Easi 9 boards and only fit the Acti 9 boards
 
Have not tried old Rcbos in the new Acti 9 boards.
Due to the fact, the old style are obsolete, we do have problems fitting the new rcbo,s in the older boards, mainly they dont seem to clip in right, though occasionally do fit.
physically the fitting looks identical, so it seems odd, we recently reused the mcbs in a damaged board and the old style mcbs fitted the new board fine, the issue seems only with the rcbos.
So yes I would agree that its possible you could have rcbo problems
As per others id get the latest cream colour ones so all looks neat
Also , im not sure you intended to, that them ones in the pic fit Easi 9 boards and only fit the Acti 9 boards

Thanks for the warning.
The images I used were just to illustrate the difference between the two types, after reading/responding to iggifer's post - and they're second hand to boot. Not the route I'm going.

PatsPatter
 
I'm preparing to bite the bullet, so have I got this anywhere near the mark?

First: the plastic Schneider CU will be going. It's not Amd 3 compliant and I'll just have to swallow the probable waste of the MCBs/RCBOs in there. Some of the MCBs may find a use in the shed/garage/workshop, where appearance isn't a consideration.

I suspect from the reactions, the idea of using three, smaller CUs for the domestic side each with a RCBO and MCBs and one taken from each phase in the Acti 9, is not viable. The idea was to balance the load but from what I can now see that it may be better done by taking each domestic circuit directly from the Acti 9 board on a RCBO and balance the load across the phases that way.

Is the following safe/compliant/sensible.

1. Use only "the lovely Schneider 12 Way TP+N board", with RCBOs on each way for the domestic circuits, and …...

2. Will that option dictate the use of individual RCBOs on each phase of a TP circuit going to, say, a TP machine tool and the TP heating system?

Regardless of the above, what connection would be made to the incoming side of the TP board? a TP-type RCBO, individual RCBOs. or just a MCB?

As I said before, I want to understand what's needed for this little lot to be safe and sensible.
I'm extremely grateful for all the advice so far and certainly don't wish to cause any offence to the professionals on here - but:
I've had one, quite expensive, experience from someone who ought to know better and I don't want another.

PatsPatter

ps I've just found a circuit in the garage that's live, even with it's MCB tripped…………..:(
 
My advice would be to utilise single phase before your domestic wiring. Having three phase in a domeati installation is pointless. Furthermore it is likley to cost more and perhaps more worrying more dangerous due to the elevated fault currents in a three phase system.

Consider this. If somehow you cause a fault in your home on a single phase you only have 230V between phase and ground. Do that on a three phase system and you will have up to 415V, depending on how you are wired.
415V is an entirely different ball game in terms of potential damage that can cause!

Continue to use the three phase before your workshop only and stick to standard single phase for your domestics.
 
. but if the TP board has a 63 amp and the CU a 50 (electric shower - and the max I'm ever likely to need), then won't the CU go first and leave the TP alone?
For a moderate overload it would.
For a short circuit where 100s or 1000s of amps will flow, both devices will disconnect in approximately the same time (a tiny fraction of a second), so there is no way to know which will disconnect first.
 
For a moderate overload it would.
For a short circuit where 100s or 1000s of amps will flow, both devices will disconnect in approximately the same time (a tiny fraction of a second), so there is no way to know which will disconnect first.
Ta, flameport, I understand that, now.
Are you saying that as a resulting of reading my post from 9.00 am Monday (3rd Oct) ?
I had thought that my wrong assumptions were corrected by the summary I wrote at 10.26am, yesterday - three posts back.
I'd appreciate your views again, if any different, after reading it.

PatsPatter
 

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