egc

[four]

I have seen several 200 amp panels that are wired accordingly:
# 6 bare copper ran from ground rod to meter can and from meter can to 200 amp panel in house
#6 bare copper ran from panel in house to first five feet of water pipe in house
My question is should the wire ran from panel to water pipe be #4 instead of #6
250-52 A1 states the 5 ft rule for being used as aEGC
250 53D2 states need for supplemental electrode
250-53E states sole connection to ground rod need not be bigger than #6
250-66 says go to t250-66 for size of EGC except as permitted in 250-66A thru 250-66C
I can see how the Egc going from ground rod to panel is #6 but I cant get out of this how the EGC going from panel to water pipe is also a #6. Shouldn?t be a #4. Any help on this one is greatly appreciated

 

[dereckbc]

Re: egc

I think you have your terms confused. Table 250.66 is for a ground electrode conductor (GEC), and bonding jumpers, not EGC. The GEC is selected from table 250.66 based on the service entrance conductor size. Simply determine what the SE conductors size is by looking at them. There is no requirement for the bonding junpers to be any larger than GEC.

Equipment grounding conductors (EGC) are based on the OCPD size per table 250.122.

Hope this helps.

Dereck

 

[four]

Re: egc

dereck:
thanks for the correction i was typing this real fast and had a brain fart. it just seems confusing to me when i see a #6 going to water pipe from panel and t250-66 to me says that should be a #4 according to service entrance conductor sizing. I wasent sure if i was reading something wrong or the AHJ says this is alright. I was just wondering what was up to code . thanks for the help

 

[alex winkler]

Re: egc

Four,
Dereck is correct that the grounding electrode conductor (GEC) is sized useing 250.66 based on the service-entrance conductors.

The service conductors for a 200amp dwelling per 310.15(B)6 should be 2/0 copper or 4/0 al minimum.

The connection to a rod electrode does not need be larger than #6 CU per 250.66(A).

The connection to a water pipe 250.52(A)1 is sized per 250.66 useing table 250.66.

The GEC for a service with 2/0 CU service conductors (200 amp)to the water line per 250.66 would need to be #4 copper or #2 Al. Note: I never use AL for a GEC.

 

[dereckbc]

Re: egc

Four, you need to check your service entrance conductor size. Should be a minimum of a 2/0 AWG copper or 4/0 AL.

As Alex pointed out the GEC from panel to water pipe should be a # 4 AWG, and bonding jumper to ground rod a # 6 AWG.

 

[four]

Re: egc

Alex:
That is what i thought it should be according to code, but i see #6 ran from panel to waterpipe alot and i was tring to find exception or reasoning behind why this seems to be legal. The AHJ seems to except #6 and i cant figure out why. I quess i'll have to ask to find out.