for working clearances do you use the 150v+ row in the 110.26 table for 208v and 240v ?
No, you use 0-150V. Notice it says "nominal voltage to ground." 208 and 240V systems are 120V to ground (nominal)
I cant beleve how many get this wrong ontests.I know sme who dont agree with Nick. can 240 go throgh you to ground?
Becareful if the 240 is 120/240 4 wire delta. Then the voltage to ground is 208.
Don