ryan_618
Senior Member
- Location
- Salt Lake City, Utah
How do you do a ground-fault calculation if you are using a raceway as an equipment ground? Is there somewhere that you can find the resistance properties of a particular type of conduit?
If you are a code geek what the heck does that make me.Originally posted by ryan_618:
in fact I'm just a code geek
A code geekOriginally posted by iwire:
If you are a code geek what the heck does that make me.Originally posted by ryan_618:
in fact I'm just a code geek
So, the rest of article 250 would allow the installation described in my previous posts.250.4 General requiremwnts fro grounding and bonding.
The following general requirements identify what grounding and bonding of electrical systems are requied to accomplish. The presciptive methods contained in Article 250 shall be folowed to comply with the performance requirements of this section
It does not say it must be capable of operating the OCPD, only that it must safely carry all the current likely to be imposed on it.a permanent, low-impedance circuit capable of safely carrying the maximum ground-fault current likely to be imposed on it
Why is that?a permanent, low-impedance circuit capable of operating the over current protective device
edited to include Pierre's quoted text!For a 500 foot run, one will most likely increase the size of the phase conductors. With that increase, a proportionate increase in the EGC as well. The raceway itself does not change in resistance, but the increased size of the EGC will have less resistance. Ohms Law tells us most current will travel through the least resistance, with some current flowing on the smaller resistance as well - no??