Hi All

I have another question about splitting the damn DB.

Essentially, I have 3 sources coming to my DB. These are Eskom, Inverter, Generator. I have figured out the way I want to connect these and looking at examples I will need 3 DBs.. minimum.

However, SANS also emphasises the importance of "turning of the entire DB Bord". So Im not sure...

1. I put each supply's double pole isolator at the start of each DB. This seems the normal way to do it... But a little silly.

2. I have a single DB called "Main" which has the 3 supply isolators next to each other. I mean, logically this seems the safest option to me. Just flip everything off on this DB and everything is safe. However, in this case, I will have all 3 supplies in 1 DB which doesn't sound legal.

3. Get a 6 pole rotary main isolator. Just flip this off, it can even be mounted outside the panel per SANS, and you are safe.

Any opinions? I still can't find the SANS regulations for splitting DBs I think its absurd.

Thanks

 

14 hours ago, ec.brink said:

Hi All

I have another question about splitting the damn DB.

Essentially, I have 3 sources coming to my DB. These are Eskom, Inverter, Generator. I have figured out the way I want to connect these and looking at examples I will need 3 DBs.. minimum.

However, SANS also emphasises the importance of "turning of the entire DB Bord". So Im not sure...

1. I put each supply's double pole isolator at the start of each DB. This seems the normal way to do it... But a little silly.

2. I have a single DB called "Main" which has the 3 supply isolators next to each other. I mean, logically this seems the safest option to me. Just flip everything off on this DB and everything is safe. However, in this case, I will have all 3 supplies in 1 DB which doesn't sound legal.

3. Get a 6 pole rotary main isolator. Just flip this off, it can even be mounted outside the panel per SANS, and you are safe.

Any opinions? I still can't find the SANS regulations for splitting DBs I think its absurd.

Thanks

 

Although this might not help you but I think the reason for SANS calling a main switch in each DB as it is not very normal (before PV) to have 2 or more DB in close proximity. 

Also my thinking is each source must have a MCB as cable protection and think if your 3 AC sources have MCB and labelled as A B and C main switch it is fine. Also a note that the DB is fed from 3 AC sources.