P
pt elec
Hi guys, I am looking for a bit of info on an installation I have recently been to look at that has puzzled me because I dont understand how it works. Hope someone can give me the answer to this one as it has going through my mind for months trying to figure it out. The situation is this.
It is a block of quite new appartments, all have electric panel heaters (on average 6 x 2.5kw) in each appartment.
Each appartment has its own supply (1 x con unit for power and lighting etc, I will call this BD1 and another con unit for electric heaters DB2)
My question is:-
Con unit DB2 (heaters) has a contactor and 6 x 16 amp MCB's, each feeding electric panel heaters as you would expect, but this Consumer unit is fed from DB1 on a 16amp MCB with 2.5mm twin & earth cable into the supply side of the contactor in DB2.
The contactor is switched from a programmer (no problem, all works fine).
What I need to know is why the 16 amp MCB in DB1 feeding the contactor in DB2 on 2.5mm Twin & Earth cable does not trip due to the overload when all 6 heaters are running ??
There is no other supply i.e tails etc in DB2 taking the load after the contactor has kicked in !! It is all on the 16amp MCB and the 2.5mm cable from DB1.
How is this possible ??
Not that it makes any difference to my question but there are about 30 appartments within this block, I have been into maybe half of these and all are wired the same and work fine.
Thanks in advance.
It is a block of quite new appartments, all have electric panel heaters (on average 6 x 2.5kw) in each appartment.
Each appartment has its own supply (1 x con unit for power and lighting etc, I will call this BD1 and another con unit for electric heaters DB2)
My question is:-
Con unit DB2 (heaters) has a contactor and 6 x 16 amp MCB's, each feeding electric panel heaters as you would expect, but this Consumer unit is fed from DB1 on a 16amp MCB with 2.5mm twin & earth cable into the supply side of the contactor in DB2.
The contactor is switched from a programmer (no problem, all works fine).
What I need to know is why the 16 amp MCB in DB1 feeding the contactor in DB2 on 2.5mm Twin & Earth cable does not trip due to the overload when all 6 heaters are running ??
There is no other supply i.e tails etc in DB2 taking the load after the contactor has kicked in !! It is all on the 16amp MCB and the 2.5mm cable from DB1.
How is this possible ??
Not that it makes any difference to my question but there are about 30 appartments within this block, I have been into maybe half of these and all are wired the same and work fine.
Thanks in advance.
