Electric power jacks

[jonesjax]

trying to calculate the load and conductor size for a sub panel for 6 electric pallett jacks these are the one's that you walk with. I am comming off of a 3 phase 120/208 panel. I am installing a new panel out behind where the trailers are about 50 feet away.around the plant they just plug them into any receptacle they can find. these are going to be one per tractor trailer. the jack will ride with the truck in the trailer. maint. man said they pull 12 amps on the internal battery charger.
thanks

 

[iwire]

I am not great at calculations but here is how I would do it.

Should be interesting to see if it works.

6 - 12 amp, 120 volt chargers.

6*12*120=8640 watts.

8640/208/1.73=24 amps needed per phase.

If we think the chargers are continuous and simultaneous loads we should add 25%

24*1.25=30 amps

So it appears load wise a 30 amp 208Y/120 feeder to a 30 amp rated panel would cover it.


Where are you mounting the panel?

If it is on it's own rack it will be required to have a service rated (225.36) disconnecting means no less than 60 amps (225.39.(D))along with a grounding electrode system.(250.32(A)

The receptacles will need bubble covers (406.8 (B) and if accessible to the public may need to be GFCI (210.8(B)(4)

Considering 225.39(D) and 225.36 I recommend using 6 AWG and installing a 60 amp feeder to supply a service rated 60 amp main breaker panel.

 

[jonesjax]

Electric lift

Electric lift

thanks Bob my my partner stuck his hand in front of a sizzer lift Fri on this job so i am solo for about 8 weeks just in time for Christmas. He broke his hand while putting it back on the trailer. Crazy he just got out of the air force as a arabic interpeter then this job gets him.

I am feeding from a sub panel on site at the guard shack going to put another panel on the building in site of the outlets for safety reasons. from there i am simply going to run individual lines.

thanks for the help my mind is not all on the job calculations righjt now...