Old double-throw switch

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tonype

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Home connected to a WWII army surplus generator (Willy's engine). Cable from the generator is connector to the top "on" postion; power grid connected to the lower "on" position. This way, the generator is isolated from the public grid.

Switch is rated for 100-amps; however, main breaker and SEC (outside) are 200-amps (and was represented by Seller as 200-amps). However, this switch is the weak link and I am calling this a 100-amp system.

If this switch is replaced, can this be swapped out with a 200-amp rated switch, or will a whole host of updated code requirements have to be met? My feeling is the latter will be required at a big expense.
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tonype said:
Home connected to a WWII army surplus generator (Willy's engine). Cable from the generator is connector to the top "on" postion; power grid connected to the lower "on" position. This way, the generator is isolated from the public grid.

Switch is rated for 100-amps; however, main breaker and SEC (outside) are 200-amps (and was represented by Seller as 200-amps). However, this switch is the weak link and I am calling this a 100-amp system.

If this switch is replaced, can this be swapped out with a 200-amp rated switch, or will a whole host of updated code requirements have to be met? My feeling is the latter will be required at a big expense.
View attachment 6151View attachment 6152
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Is the main breaker before the switch?
Are you switching the neutrals? The switch must be changed to the large amp load.
 
Feed from the main panel comes in at the lower left - connects to the bottom set of lugs; generator feed comes in at the bottom and routed to the top lugs.
 
From what I see you need to replace the switch with a 200amp rated switch.
Unless you are running the gen. as a separately derived system the neutrals need to be bonded together and isolated from the can.
Then you need an EGC from the service disco, generator, (where the neutral and EGC are separated) bonded to the can then a EGC ran to the MDP where grounds and neutrals are separated.
 
I think Square d still makes those switches, I have several laying around my shop. Depot used them as a isolation switch between their Sola power conditioner, and the redundant back up transformer for the computers and registers. They have since done away with them and installed a single UPS unit.
 
Little Bill said:
What are the smaller wires in the switch?
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Two armor-clad circuits - also calling that a potential problem. Don't know where they go (no indexing). There is no visible overcurrent protection other than the 200-amp main outside (could be something local at a piece of equipment.
 
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