couple of quick questions

[rickl]

i have a little project that needs to be finished this weekend & i have a couple of question that i can't find the answer for in the nec
i need to run 3 300' straight runs of 1 1/4" pvc conduit , in 2'- 3' ditch all 3 will 90 up at both ends & will not be securely mounted on either end,with a pull string in each, question should i or would you install expansion joints in this situation? once its covered i don't think the temperature will change that much ( pacific northwest)
also HO has a 60 amp temp power pole installed by transformer now he wants power to his temperary well shed about 50' from transformer ( after the house is built the shed will be move to another location) the shed will also house a computer & security cameras so he can monitor the contactors from his home 100 miles away. question can i feed a 30 amp sub panel to the outside of the shed from the temp power, 4 wire uf buried 2' deep all exposed wiring in conduit, also if i can will i need a main breaker at the sub panel or can i use main lug panel. there will be 1-2pole breaker & 1 or 2 single pole breakers in sub panel.

thanks for your input

 

[bradleyelectric]

i have a little project that needs to be finished this weekend & i have a couple of question that i can't find the answer for in the nec
i need to run 3 300' straight runs of 1 1/4" pvc conduit , in 2'- 3' ditch all 3 will 90 up at both ends & will not be securely mounted on either end,with a pull string in each, question should i or would you install expansion joints in this situation? once its covered i don't think the temperature will change that much ( pacific northwest)
also HO has a 60 amp temp power pole installed by transformer now he wants power to his temperary well shed about 50' from transformer ( after the house is built the shed will be move to another location) the shed will also house a computer & security cameras so he can monitor the contactors from his home 100 miles away. question can i feed a 30 amp sub panel to the outside of the shed from the temp power, 4 wire uf buried 2' deep all exposed wiring in conduit, also if i can will i need a main breaker at the sub panel or can i use main lug panel. there will be 1-2pole breaker & 1 or 2 single pole breakers in sub panel.

thanks for your input

no expansion fittings, run the temp to the shed as described, use a MLO panel with a 30A breaker backfeeding the panel, remove the main lugs, put the lock down screw or whatever the manufacturer has to secure the breaker for this application. check with authority having jurisdiction outlining this plan before proceeding, he may want a ground rod at the sub panel also.

 

[rickl]

so i need a main disconnect at the sub panel even if its within sight & within 50'(mounted outside of shed)

 

[bradleyelectric]

so i need a main disconnect at the sub panel even if its within sight & within 50'(mounted outside of shed)

They might let you get away without it. Ask the AHJ. It is a seperate structure by itself. Not as if it is in the same structure.

 

[e57]

the shed will also house a computer & security cameras so he can monitor the contactors from his home 100 miles away.

Sounds like Big Brother - but I say this as can see my truck on the same monitor I'm typing on to from a camera mount in a flower pot out front.:wink:

FYI a 2-pole 3-wire circuit counts as one via 225.33B, but sounds as if you would want a main at that panel anyway IMO

 

[Dennis Alwon]

The panel is being fed with a feeder not a mwbc therefore you would need to drive a 2 ground rods at the building unless you get the 25 ohms to ground on one rod. Since you only have less than 6 breakers then, IMO, no main is need at the structure.

 

[bradleyelectric]

The panel is being fed with a feeder not a mwbc therefore you would need to drive a 2 ground rods at the building unless you get the 25 ohms to ground on one rod. Since you only have less than 6 breakers then, IMO, no main is need at the structure.

If it was more than a 6 circuit panel, ie 4/8, they would want a main in my home county. They also except 1 rod. That is why I like to preface the things I say with "Tell the AHJ your plan and have him ok your plan". They are very good about having things bounced off of them on the phone, and if its got some teeth to it, they will let you pull the permit and schedule an investigation inspection before you start, or a progress inspection if you've already started.