Do you ever size your generator conductors and 125% for continuous load possibility?

[marmathsen]

If you don't know the complete load to be supplied by a generator because some of that load includes general use outlets and lights, does anyone ever oversize conductors with the theory that it might be run at 100% capacity for more than 3 hours?

I'm thinking specifically about a portable generator feeding a residence, but I assume the same question could be asked about other scenarios. If the permanent heating system can't be powered by the generator one would assume that portable space heaters would be used and likely could be running for 3+ hours.

I you don't oversize, do you leave instructions with the user stipulating no more than 80% for 3+ hours?

 

[ActionDave]

If it's a permanent generator there is no way I would size a generator too small to carry the central heat.

If it's a portable generator I would size the conductors for the generator, maybe add a little headroom for some future expansion. If for some reason the HO decides to turn on every light and plug in every space heater, curling iron, blender and microwave in the house while the utility is out then the generator is going to bog down and the party will have to be scaled back.