Phase rotation

[Rikki]

Hey guys just wanted opinions.....

I am adding a 3ph 63a switch fuse into the main DB in a warehouse.... now I tested phase rotation, and on the left handside of board I am getting L1/L2/L3. 

on the right handside of the board I am getting L1/L3/L2! so I guess there has been a crosss within the bars behind somewhere. 

I know previously they had problems with some 3ph motors, so they swapped phases at load ends. I believe I should install my equipment in the correct sequence as at the board (Br/Gy/Blk) to match L1/L3/L2 and mark up correctly at board. Do you guys agree with this? With regards good practise my head is telling me that I should resolve the problem at board and also at motor isolators too. 

 

[Andy™]

sounds like an MCCB panel in which case its completely normal since the L1L2L3 termianls are set by the MCCB (and so if its on the LHS L1 is on the top, same MCCB on the RHS and L3 is at the top) and not the busbar like an MCB...

 

[Rikki]

Hi Andy, yes you are right it is an MCCB panel. Looking at photos of panel I have, it is wired r/y/b on left and b/y/r on the right. 

This has been very helpful thank you. 

 

[poni]

so if its on the LHS L1 is on the top, same MCCB on the RHS and L3

is this true? i thought that if L1 at the top on the right it would L1 at the top on the left as well, maybe i have just not seen this type of board 

getting L1/L3/L2

are you sure its like this ? do you have a photo?

 

[Andy™]

is this true? i thought that if L1 at the top on the right it would L1 at the top on the left as well, maybe i have just not seen this type of board 

are you sure its like this ? do you have a photo?

yep. at least it is on every MCCB panel ive worked on.  so if you were to connect RHS in this pic as L1L2L3 from the top then you would get reverse rotation  since youve swapped L1 & L3

 

[poni]

Yes I see it's the pickups are on the breaker, and I have fitted this type before,the contacts are steped back from each other ,also when you need single phase ones you have to ask for the phase you want ,why did I not remember this?

Old age is a terrible thing

 

[Andy™]

Yes I see it's the pickups are on the breaker, and I have fitted this type before,the contacts are steped back from each other ,also when you need single phase ones you have to ask for the phase you want ,why did I not remember this?

Old age is a terrible thing

yep. each position has all 3 phases available, the SP breakes are ordered with what phase you want

 

[Phoenix]

Its not so much an MCCB thing as a schneder mccb thing, most other makes of panelboard just have tabs that the breaker goes onto like a normal MCB board, hager and dorman smith certainly are and I think wylex too

 

[Andy™]

Its not so much an MCCB thing as a schneder mccb thing, most other makes of panelboard just have tabs that the breaker goes onto like a normal MCB board, hager and dorman smith certainly are and I think wylex too

 guess its just schneider boards im used to working with. thinking about it i think the wylex i done an EICR on a few weeks ago was L1L2L3 on both sides