Hybrid circuits

[Pete999]

Morning all, been pondering quite a bit lately about Hybrid circuits,especially 13amp socket circuits, the likes of lolly pop rings etc.

I don't want to get into arguments about the pros and cons and why people install them, that's been done to death, whether, I personally agree with this method is neither here nor there, no, my question is, " how are these circuits tested, and how are the results entered on the installation certificate?" for example if you have installed a lolly pop ring how is that described? as a ring or a radial.

 

[VoltzElectrical]

That's because you're a electrical trainee, you can't see any further than what's covered in BS7671 and the picture book OSG and the like!!

From a bloke that won't stand looping in at switches and would have them ripped out if installed on 'his' job?

You can LOL your way off this thread, the double standards are that laughable.

 

[7029 dave]

30 Amp switch. Never used them myself.

 

[VoltzElectrical]

30 Amp switch. Never used them myself.

I have. To isolate a cooker, for example, i.e. a single point. I've just never heard of using them to isolate a whole bunch of sockets. Oh well, every day's a school day I suppose. Thanks for the education.

 

[davesparks]

Sorry guys, I have worked on projects that have included 2 hospitals, 3 student accommodations, 1 cinema/ theatre, fire station, various domestic, 2 schools lalalalala.

I'm no Electrical Trainee, but I'll put my hands up, I haven't seen everything. Now I'm flummoxed on two things in one day.

1. Lolipop rings. Sound yummy, but on further investigation, not so nice.
2. Using 32 amp switches to isolate socket circuits? Not in my experience.

I must be lacking. Luckily not in the trouser department!

There's an College local to me where every classroom has a 6mm feed to a 32A switch then a ring after that which is used for all of the classroom electronics, they get switched off every night.
Also the same in the 2x recording studios in that college.

Most theatre installations I have done have included both general and specific socket circuits controlled by DP switches, some 20A and some 32A.
Again this is so that sockets can be switched off at night/when not needed.

As a user of such facilities it really winds me up when the designers/installers don't think to provide such facilities.
By all means fit lots of sockets in the orchestra pit, but give us a switch to turn them off with! Fighting your way through the music stands and instruments to switch off the stand lights every day is not cool.
As for going round the stage switching off every smoke/haze/snow machine, fan, TV monitor, props table etc etc, it gets ridiculous!

 

[VoltzElectrical]

There's an College local to me where every classroom has a 6mm feed to a 32A switch then a ring after that which is used for all of the classroom electronics, they get switched off every night.
Also the same in the 2x recording studios in that college.

Most theatre installations I have done have included both general and specific socket circuits controlled by DP switches, some 20A and some 32A.
Again this is so that sockets can be switched off at night/when not needed.

As a user of such facilities it really winds me up when the designers/installers don't think to provide such facilities.
By all means fit lots of sockets in the orchestra pit, but give us a switch to turn them off with! Fighting your way through the music stands and instruments to switch off the stand lights every day is not cool.
As for going round the stage switching off every smoke/haze/snow machine, fan, TV monitor, props table etc etc, it gets ridiculous!

That's a very interesting input, and obviously something I haven't yet come across in all the projects I've been involved with. I think the OP was referring to a domestic setup though.

 

[VoltzElectrical]

There's an College local to me where every classroom has a 6mm feed to a 32A switch then a ring after that which is used for all of the classroom electronics, they get switched off every night.
Also the same in the 2x recording studios in that college.

Most theatre installations I have done have included both general and specific socket circuits controlled by DP switches, some 20A and some 32A.
Again this is so that sockets can be switched off at night/when not needed.

As a user of such facilities it really winds me up when the designers/installers don't think to provide such facilities.
By all means fit lots of sockets in the orchestra pit, but give us a switch to turn them off with! Fighting your way through the music stands and instruments to switch off the stand lights every day is not cool.
As for going round the stage switching off every smoke/haze/snow machine, fan, TV monitor, props table etc etc, it gets ridiculous!

On the original thread though, are these circuits you are describing 'lollipop' rings, or locally isolated radials? As surely that is the point of this discussion? I'm not arguing against local isolation!

 

[davesparks]

On the original thread though, are these circuits you are describing 'lollipop' rings, or locally isolated radials? As surely that is the point of this discussion? I'm not arguing against local isolation!

In the college they are all lollipops as I described.
Not my design or installation though, and probably not the way I would have done it.

 

[Leesparkykent]

That's because you're a electrical trainee, you can't see any further than what's covered in BS7671 and the picture book OSG and the like!!

a bit uncalled for!!!

 

[andyelectric]

a bit uncalled for!!!

Seconded.

This Electrical Trainee can see nothing against a lollipop circuit. Domestically I can see the advantage of reusing a cooker point to save for example floors being ripped out. But I'm with HHD in that I'd run a radial if possible, though if 4mm cable can't be accomodated as Murdoch has said why not lollipop.

Industrially Davespark has made some v good points as he usually does. Might it also be used for volt drop reasons just installing a switch as opposed to a sub db if only one cct.

 

[Knobhead]

BS7671 is a set of Regulations, not a How to do book.
It is also produced by a committee.
As such only standard circuits are shown, as they are the only circuits everyone on the comitee agree about.
I take it that you have not experienced Spider circuits, or Spider Rings?
I have no idea who came up with such a circuit, but they need a good spanking.

Spider web is properly called Octopus wiring. In some situations like lollipop wiring it is the most suitable.

As E54 pointed out, just because it’s not in the join the dots comic (OSG) doesn’t make it wrong. If you don’t understand the theory who’s fault is that?

Say you were come across either system on a EICR what would your reaction be?

 

[Knobhead]

a bit uncalled for!!!

Totally called for and perfectly true.

 

[davesparks]

Industrially Davespark has made some v good points as he usually does. Might it also be used for volt drop reasons just installing a switch as opposed to a sub db if only one cct.

Yes it can be used for volt drop reasons.

But a switch cannot be used in place of a DB! And I don't see why you would want to put a DB in the middle of a final circuit????

 

[Pete999]

That's a very interesting input, and obviously something I haven't yet come across in all the projects I've been involved with. I think the OP was referring to a domestic setup though.

No not really, just hoping for some thoughts, got plenty so far thanks

 

[andyelectric]

Yes it can be used for volt drop reasons.

But a switch cannot be used in place of a DB! And I don't see why you would want to put a DB in the middle of a final circuit????

I was just using a the analogy of a db supplying more than 1 final cct as opposed to a switch supplying the lollipop head in the middle of a final cct.

A spider/octopus circuit is just a radial with multiple spurs from the same point so just a pain for testing.

I can't get my head round a 'spider ring'. Sounds like a lollipop with a figure of eight ring to me, which surely can't be compliant.

Spider ring??

 

[Flanders]

Back to how to certificate it I would use 2 lines on the circuit scheduled one for the radial to the switch a one for the ring and then write it up as information on the observation page