Surge Arresters on dual feed 5kV Switchgear

[allsgo]

I have a dual (primary and emergency) fed 5kV Switchgear that powers several pumps, fans, and transformers. The surge arresters are located on the load side of the primary and emergency breakers. These breakers can't be closed at the same time. The secondary side of the 2 transformers feeding this gear don't have surge arresters, the primarys do. It has been brought up that it would be best to move the surge arresters to the line side of the breakers to protect the secondary side of the offline transformer while that breaker is open. The switchgear and the secondary side of the online transformer would be protected with the closed breaker. Long question short, is it best to have surge arresters on the line or load side of switchgear main breaker(s)?

 

[odlanor]

it depends of distance between scary trasnfer ann load. make a sketch of xmtr, CB ,arester, load and distance

 

[odlanor]

it depends of distance between secondary transformer and load. Make a sketch of xmtr, CB ,arester, load and distance

 

[odlanor]

1-it depends of distance between secondary transformer and load. Make a sketch of xmtr, CB ,arrester, load and distance
2- Why to protect the secondary side of the offline transformer that is not in operation?