Overall main switch where the installtion has off peak heating ?

[spud1]

What is everyone's general procedure for provision of an overall installation main switch isolator where an installation has two DB's - one off peak, one on peak? Is it crucial a linked 4 pole main switch be installed to isolate both sets of tails or can a dispensation be made with some clear labelling?

 

[Pete999]

What is everyone's general procedure for provision of an overall installation main switch isolator where an installation has two DB's - one off peak, one on peak? Is it crucial a linked 4 pole main switch be installed to isolate both sets of tails or can a dispensation be made with some clear labelling?

Using a 4 pole isolator, would isolate both CUs causing unnecessary disruption for your clients, not sure if a 4 pole isolator would be compliant anyway.

 

[Des 56]

edited

 

[Richard Burns]

Obviously the ideal is a four pole isolator, however there is some consideration that the post Des56 has just made is the point I was to make! Too slow.

 

[PEG]

The suppliers must consider them to be compliant,as they fit them,albeit under some duress...due to cost and fitters lack of training,i would guess.

I would not judge any disruption,as a good enough reason,not to.

There is a very easy to understand,risk assessment,when considering the skills of a possible individual,and their possible reasons for needing to isolate,which the suppliers hear once,and simply fit one.

A great deal of the properties round here,are dual rate,from the sixties,and have all manner of "additions" and cross-overs,which include other circuits and single sockets,which are fed from the low rate meter.

The issues this can present,can best be mitigated against,by having an obvious,single point of isolation,an uninstructed person,can find easily.

 

[FatAlan]

Interesting question. I have a scenario with a DB split with RCD protected and non RCD protected circuits, a second separate DB with two further RCD protected circuits plus a third off peak board. See attached photo. How would folks organise in respect of isolators?

 

[MJPD29]

Not relevant but I do love where the water/heating pipes come out really intelligent plumber

 

[Taylortwocities]

How would folks organise in respect of isolators?

2-pole isolator between meter and henley block. Simples

 

[FatAlan]

What about the live feeds from the cut out that go to that off peak control unit?

 

[Deleted member 26818]

What is everyone's general procedure for provision of an overall installation main switch isolator where an installation has two DB's - one off peak, one on peak? Is it crucial a linked 4 pole main switch be installed to isolate both sets of tails or can a dispensation be made with some clear labelling?

That would be two installations, so two main switches.
Could link the two installations together with one switch if you want.

 

[Wilko]

Hi - that’s a bit of a mad person’s breakfast ... Perhaps ask DNO to supply an isolator? Or use a 4 pole yourself.

 

[Midwest]

edited

Obviously the ideal is a four pole isolator, however there is some consideration that the post Des56 has just made is the point I was to make! Too slow.

What was his/your point?

 

[Midwest]

Perhaps in the confusing set up that FatAlan posted, one isolator would a consideration. But in a simple set up with DB's side by side and clearly labelled, I see no need for one point of isolation.

And I know this has been argued before, i.e. disconnection of supply.

 

[Charlie_]

2 DP isolators side by side in an enclosure.. 1 labeled DB1 the other DB2?

 

[Richard Burns]

What was his/your point?

It is two installations

 

[FatAlan]

Hi - that’s a bit of a mad person’s breakfast ... Perhaps ask DNO to supply an isolator? Or use a 4 pole yourself.

DNO is UKPN who won’t provide isolator. Apparently I have to speak to supplier which may make sense if also dealing with an off peak supply as well.

 

[Des 56]

What was his/your point?

Nothing worthy of note.
Sorry it was unfortunately quickly deleted,thats after I became aware I was possibly once again going on one of my regrettable rants

 

[spud1]

I confirmed your helpful answers with some good old fashioned book wormin! Guidance note 2 section 4.2 page 48 (in the 18th edition version). TWO MAIN SWITCHES IN DIFFERENT CUs is FINE SO LONG AS APPROPRIATE LABELLING IS PRESENT. Thanks for all your replies.