Tap conductors for three AC units

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Genuine

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The existing installation consists of this:
200 A 120/240 V single phase residential electrical service, installed circa ~1970.

200 A Fusible disconnect located Back to Back with the electrical meter.
The load side of the disconnect feeds ~4/0 AL to a 200 A load center panel (~40' away) with a 200 A main breaker, AND also via additional lugs on the load side #2 AL through a 30' run of 1" EMT to an exterior mounted 100 A fusible disconnect switch with 100 A fuses.

The load side lugs feed three sets of conductors (all less than 25' in length) to three fusible disconnects.

Unit #1 has #8 fused according to the AC's Max of 50 A with 50 A fuses
Unit #2 has #8 fused according to the AC's Max of 25 A with 45 A fuses
Unit #3 has #10 fused according to the AC's FLA of 9.5 with 20 A fuses

A few concerns exist...
1) The length of the #2 AL conductors to the 100 A fusible disconnect.
2) Sizing of the fuses for the #2 AL.
3) Triple lugging of conductors on the load side of the 100 A fusible disconnect.
4) Is this considered a tap of a tap? Or does the second set of fuses permit this?

Obviously the AC fuses need to be properly sized.

Are there any other code concerns regarding this installation?

Thanks!!
 
Genuine said:
A few concerns exist...
1) The length of the #2 AL conductors to the 100 A fusible disconnect.
2) Sizing of the fuses for the #2 AL.
3) Triple lugging of conductors on the load side of the 100 A fusible disconnect.
4) Is this considered a tap of a tap? Or does the second set of fuses permit this?

Obviously the AC fuses need to be properly sized.

Are there any other code concerns regarding this installation?

Thanks!!
Click to expand...

#1 Nothing wrong with the length of the #2 conductors.
#2 Change the breaker to 90 amps to the Fuse Disco
#3 Triple lugging would not be legal since I doubt the terminal is listed for triple lugging
#4 I am not sure

The fuses to the AC are more than likely appropriately sized even though the wire size does not match the fuse size. Read art. 440.22
 
Clarifacation to my original post and additional question

Clarifacation to my original post and additional question

Just to be clear...
The 1" EMT conduit runs inside through the unfinished basement.
The 200 A fusible disconnect is located indoor, in the basement.
The 100 A fusible disconnect is located outdoor.

Also, was this original installation (circa ~1970's) done according to the code of the day?

Thanks!
 
The tap that is indicated is installed inside the structure and the conduit is 30 ft in length. Therefore the conductors must be 30 ft plus. I do not see a tap rule that complies with this length and on the inside. NEC 2008 240.21(B) (2)Taps not over 25 ft is the length of the conductor. 240.21(B) (5) Outside taps of unlimited length. This appears to be a violation in the 2008, 2005, and 2002 codes.
 
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