No power to CU or meter after resetting RCD

[Msitekkie]

I was working on a lighting circuit connected to a 3 phase board. The board has a single RCD effectively acting as the main switch. After tripping the RCD by cutting a wire (the old circuit isolated via MCB but Neutral still connected reason), I found that the power to the board didn't come back on after resetting the RCD. The meter was also dead.
The service head is in another premises (where the power was still on) and I found that cycling the power off & on from the upstream premises seemed to reset something & power was restored to the DB & meter where I was working. This is a TT system. The owner of the other premises was unaware of any other infrastructure in-between. I found this to be repeatable.
I would like to understand what happened here.
Has anyone else come across this scenario who could suggest why this happened and how cycling the power brought ?

 

[Andy78]

What device did you cycle off and on in the upstream premises to reinstate power ?

 

[Msitekkie]

I was afraid someone was going to ask that question. The owner of the premises was talking confidently about it as if it was an RCD, saying it hadn't tripped, but it looked more like some form of isolator to me - a square grey metal box with a white up down switch. (He was a bit dismissive & the situation didn't encourage me to linger). The box was quite large in proportion to the size of the switch.

 

[James]

What device did you cycle off and on in the upstream premises to reinstate power ?

Was it an rcd that had tripped to the mid point?
Turn off reset it, turn on re energised supply

 

[James]

@Msitekkie
I think you have answered your own question.
(In your head, not on here)

 

[freddo]

Perhaps an MCCB with a tripping coil? Turning it off moved it from the tripped position to off and then back on to reset?

 

[Andy78]

Was it an rcd that had tripped to the mid point?
Turn off reset it, turn on re energised supply

Exactly what I was thinking.

 

[PEG]

Or an old VOELCB?

 

[Msitekkie]

Many thanks guys for your replies, which I will research further. I hadn't heard of an MCCB with tripping coil before - I wonder if this is something that you are more likely to see in a 3 phase scenario.

 

[freddo]

I wonder if this is something that you are more likely to see in a 3 phase scenario.

Yes fairly common, you can buy add on earth leakage kits for when you need earth leakage protection on supplies >100A
I did have a photo of one in the dodgy trade pics thread but it is gone now.

 

[westward10]

Or an old VOELCB?

I'm intrigued is it you on the unicycle.

 

[PEG]

I'm intrigued is it you on the unicycle.

....thought i was off,on a 4 pole voelcb debate.....?
Yep,it's me,many years previous,demonstrating balance,strength,and the dangers of weird company and too much free time?

I can still do that,but at 55,you have to realise the change, in things like responsibility and healing times.

I could do the same foolishness,with an old full size acetylene bottle,which is quite a bit heavier,than an oxy bottle,but did have a pedal shear off,on one occasion?

...come VERY close,to needing the unicycle,surgically removing,from me lower colon ??