13a rcbo's - a rare beast?

[Kram]

there is no way around your problem.

This house was rewired just before covid and I requested RCBO's, however the Wickes contractor fitted a small CU with a single RCD and MCB's. I was rather pee'd off about that.

When my metal melter project started tripping the whole house, the suggestions on here were to use one of these:

https://www.screwfix.com/p/carroll-meynell-3000va-intermittent-isolation-transformer-230v-230v-blue/320HV?srsltid=AfmBOopebTfJCZt5E_sQmJ3F5qw-cX8Wzf6dE7s1tdBH3CG_N_-M15yNmMY

I never got one due to lack of storage space., instead I double isolated the faulty SCR unit which was casuing the leakage.

 

[MetalMonkey]

I dont think a caterer, plugging im some extension leads and devices to a supply, could be held responsible for the sites electrical safety. That would fall to the event organiser and persons responsible for the generators.

A ring of looped consumer units doesn't sound like a couple of extension leads to me...

Any business is going to have a duty of safety to it's employees and members of the public under the electricity at work regulations. He is providing the electrical installation which they are using, and in this case also assuming the role of designing it.

Im not sure if portable kit is covered by BS7671? (I got bored of the sparky course about a month in..)

Section 717 covers mobile and transportable installations for events etc. BS7909 may also apply.

 

[hotponyshoes]

Dont trip the power off!
I am not a sparky. I assume there must be some kind of wiring standard for temporary installations and generators for event use?

Problem is, if the gen has a 30mA RCD covering everything, that has equal chance to trip as an RCBO that is downstream.

You need a unit at the generator with an RCD/RCBO for each circuit or area. I dont know if bigger generators have that.. never used one.

I wouldnt want any unprotected cables outside at an event. I have seen the state of some event cables.

My mates guitar amp had bare wire showing and some very old, unsticky electrical tape dangling from it.

It's not usually us that trips it out, I'm primarily interested in protecting people if a bit of kit gets smashed while it's plugged in.
There is always one drunk at a wedding who will climb over the barriers and fall into our table...

Most common issue I see is due to everyone wanting pretty uplighting around the sides of the marquee. After the meal the chairs get pushed to the sides of the marquee, the rubber feet are normally missing, someone sits down and the chair leg chops through the cable.

The supplied generators vary massively.
A good setup has a series of 32a outlets each protected by a 100mA rcb,
Our boxes at 30mA tend to trip out first.
Generally (for noise reasons) the generator is quite a way from the marquee so that saves us a walk..

At the other end of the scale I've seen everything. Farmers running tractors with pto mounted units held together with string is a common one.. also one occasion where the bottom of a streetlight had been opened up...

A lot of mid-size generators just have a load trip on the outlet, no protection. If that's the case I have a board to add the rcd close to the generator to protect the cable run.

 

[dobbslc]

Depending on the load of the equipment you are using you could use 10 amp RCBO'S, no good for a 3kw deep fat fryer but 2kw gear with be fine on 10 amps.
As some of the others have said it does sound like you are making yourself the 'designer, constructor, tester' of this system if it has dist boards etc.
Plug and play extension leads maybe less onerous if they are PAT "test" on them.
You can get 10ma RCBO'S and they will give you the discrimination you need to prevent tripping out the whole site.
Depending on the size of the generator they can have adjustable earth leakage sensors but this will need setting up by someone that knows what they are doing and each event will probably be different.
Personally I wouldn't get too involved with this unless you have it tested and designed properly.

 

[Hotstuff]

If you are connecting onto someone else’s installation or generator, you are still responsible for the safety of your installation.

If you connect to a dodgy electrical installation, jury rigged from local street furniture, as designer & installer, you are still responsible.

The installation (including your part) should be tested & certificated by a competent person prior to being put into service.
Correctly rated RCDs are good life saving devices but do fail, hence the need for testing.