I work in an industrial plant that just does whatever when it comes to electrical. They don't really have to follow code because they fall under MSHA. Recently they had to install a temporary generator to feed an mcc bus for some pumps. The engineers (one who supposedly has a journeymans license) had the electricians install 4/0 cable from the generator to the mcc. Not parallel either. The generator has a 1000 amp breaker. So they put a 400 amp breaker at the mcc before the buss to protect the 4/0 cable. I think they said it was 30 to 60 feet run. This engineer said that the tap rule allowed this by code. I know what rule he is refering to about outside taps but in my opinion this isn't a tap. Plus the 400 amp breaker I don't believe is correct to protect the 4/0 cable either. Is this considered a tap? Any opinions on this? Thankyou
Tap Rule???
- Thread starter tpd
- Start date
- Status
kwired
Electron manager
- Location
- NE Nebraska
Without even going into tap length requirements, the 4/0 conductor is not a 400 amp conductor.
- Location
- Massachusetts
The short answer is they are just doing whatever the heck they want to.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
IMO, this is not a tap and does not fall under the tap rule. However, it seems there is not much you can do about it.
Your right that there is not much I can do about it other than point it out that this is an unsafe installation. I know MSHA did give a citation a few years ago for putting a small temporary cable on a large breaker. But I think this is up to the inspector and his knowledge of electrical. So the next inspector might not even see a problem with it!! Very frustrating for people that believe in electrical safety!! Thanks for verifying what I thought about this problem.
Not excusing the installation, but, in that you mentioned cable and mining it is possible that the cable is a 4/0 type W, and with a motor load situation, a 400 amp breaker might be acceptable. Once you look at the actual load and consider the type cable and the "outside" tap rule the
tempo ray install might not be that grievous a situation.
tempo ray install might not be that grievous a situation.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Now I see-- I wondered what MSHA was.....
Dopey me.- Status