VRF Equipment fed off local Lighting Circuits

It's our policy that we isolate power before entering voids due to an historical issue therefore we design out the risk at design stage. If isolators are below ceilings then power is killed before entering the void above to service ny equipment - this is where I'm at - cheers

So the problem is isolating the lighting circuit before entering the void, actually you really should throw the main switch to be sure.


Andy B

Fandango:

It's our policy that we isolate power before entering voids due to an historical issue therefore we design out the risk at design stage. If isolators are below ceilings then power is killed before entering the void above to service ny equipment - this is where I'm at - cheers 

But don't appear to have done so in this case ?


I guess you are stuck with complying with policy, adding double pole lockable isolation on all sources of supply into a ceiling void  (perhaps at the Dist. Bd. location) and living with the disruption of having the floorplate unusable for any relamping activity or for the routine checking/swapout of the FCU filters and the inspection of their condensate drain traps.


To avoid the above, then you are likely to need a lot more circuits adding, or change the policy to include a "where present" circuits in voids will be isolated before access to the void is made.


Or re do the RAMS to reflect the actual risk of accessing equipment within the void


Regards


OMS

That's correct it does read where present. Also a partial isolation policy is in place which reflects the appropriate RAMS - Thanks ?

Is it not possible to make the installation within the void safe?


If this is a space above a suspended ceiling what is there to stop anyone lifting a ceiling panel to access the void?


I was in a bank in Hereford on Monday, whilst the money I was paying in was being counted there was an electrician stood on a stepladder behind the cashier with his head above the suspended ceiling undertaking some work, the bank electrical installation had not been isolated and the lights were still on, it was business as usual, working in the void is presumably not deemed potentially dangerous due to the presence of electrical cables.


Andy B.

Many years ago a plumber working for the Gas Board in Worcester died whilst working in a house whilst installing a new central heating system, he simply pushed a length of copper pipe under the floor board s into the void below them and the pipe went into an electrical junction box which did not have a lid on it.


Is that the type of risk that is present, something like that would not be found and recorded by an electrician preparing an electrical installation condition report, the report also carries a disclaimer saying that issues such as that may not have been found and recorded.


Should a domestic electrical installation be shut down and isolated every time someone enters a loft space or accesses the underfloor voids, because there are plenty of damaged and incomplete junction boxes in peoples homes as well as choc strip connectors without anything to enclose them.


In commercial and industrial installations should not such issues be dealt with?


Andy B.

Sparkingchip:

 it was business as usual, working in the void is presumably not deemed potentially dangerous due to the presence of electrical cables.


Andy B.

There are plenty of safety requirements that would disagree with you - based on a few decades of absolutely shite installers throwing stuff into ceiling voids it's not that uncommon to see all sorts of shoddy stuff that often has readily accessible exposed terminals, joints etc


A contractor working on a project for one of our banking clients actually had an operative killed, as in the process of lifting a ceiling tile (which was clipped) an exposed chock block managed to contact a suspended ceiling suspension wire and livened up the grid  - the resulting fall from no significant height from a step ladder proved fatal


Some 6 month earlier, the existing lighting system had been replaced for LED panels - difficult to fathom why, but the existing lighting marshalling boxes fed the existing luminaires via klix type sockets in 3 core flex - the contractor seemed to have decided that the LED panels only needed 2 core flex so extended the 3 core with 2 core and left all the luminaires (and consequently the grid) unearthed. Easy to see how it happens, give the apprentice a pile a fittings, a coil of the wrong flex and a box of chock blocks and tell him to flex up every fitting with 1.0m of flex - get the rest of the guys to chop off the old fitting and remove - strip the flex back and then connect up to the tail end already on the luminaire - rinse and repeat.


OMS

That's correct we had similar issue with an AC Unit years ago with a lid left off. For that reason power should be isolated before entering voids and an RA carried out. We also dont allow junction boxes unless labelled and ocated below ceilings and are accessible. This minimises the risk and was a consequence of the historical issue.

Ah! Every day I am visually risk assessing absolutely dreadful electrical installation work.


Some years ago I walked out of a job and lost two days pay to work In a bungalow, because the customer had another guy who was moonlighting from a major electrical company who had installed lights and a new shower in such a dangerous condition that I refused to finish the work I was doing and simply walked away announcing that I was not going to be involved with taking any assumed responsibility due to being there at the same time.


It sounds to me that the isolation of single items of equipment is the least of your worries, the installation just needs shutting down, even to do something as simple as changing a light fitting, because you have recorded  safety issues.


You are going to be popular!


 Andy Betteridge

It is interesting (bad word in these circumstances I know) to hear of such accidents that have actually happened. We all see potential dangers and correct/evade them at all times but knowing someone has actually come to grief under such circumstances is another thing. We see it and know the potential dangers and I`m sure we get a bit blaise about it until we know someone who knows someone then it gets a bit more eek! about it. Sad