Temp. Gen. Connection

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session88

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The Facility has two separate 60kW 208 3-Phase 4-Wire Generators. They do not sync. One of the two gen.'s feed entire facility. No utility power. Remote site.

Both generators feed the MDP thru a Manal Transfer Switch:
Manual Trans. Switch Position 1: Gen. 1
Center Off
Manual Trans. Switch Position 2: Gen. 2

What would the safest, simplest and code compliant way be to feed this system with a portable temporary generator from outside the Gen. Building thru a Pin & Sleeve (Appleton Powertite or similar) Plug and Receptacle. Once everything is installed and built the Temp. Portable Gen. will most likely have to be connected by a non-electrician at 2:00 A.M. on a weekend.

I have personally never engineered or installed a Manual Trans. Switch that can accept three separate 3-Phase Sources....

I would like to replace the existing Trans. Switch with a Manual 4-Position Trans. Switch. Three separate positions for three separate generators and an off position.
Does something like that exist in a 225 Amp Range ? or will I have to install another Manual Trans. Switch between the MDP and the existing Manual Trans. Switch ?
 
Ok I plan to "cut-in" another 400 Amp MTS between the existing 400 Amp MTS for this new temp. portable outdoor generator since I cannot find a manufacture that makes a NEMA 1 MTS between 200A and 400A. 400A is way overkill but I guess that is what I will need to use.

Do I use Table 400.5(A)(2) to size the outdoor temporary flexible cord (Type SOOW, Type G, or similar) from the Temp. Portable Gen. to the new Inlet Reverse Service Pin & Sleeve Outlet I will mount to outside of building ?

As stated above the Gen.'s are 60KW with 225 Amp Main Breakers on the Gen.'s.
We will use a similar size Temp. Portable Gen. if / when needed in an emergency if both of our permanent 60KW Gen.'s go down.

The way I read Table 400.5(A)(2) I will need 3/0 Four Conductor Flexable Cable from the Outdoor Portable Gen. to the new Inlet Pin & Sleeve Receptacle. Is that correct or is there an exception allowing for smaller Flexable Cable ?
 
Yes, 400.5(A)(2).
No exception that I know of, but pay attention to the all temperature ratings involved, you could be at 1/0 (75 deg, column D, or maybe even 90 deg column D) for this specific connection. Partly depends on whether you want a 5 wire cable or if 5 single leads will do.

Also, you're looking at $$$$ for a pin-and-sleeve connector of that rating. Is there a reason you can't use Camloks? As long as the people aren't color-blind, they're easier and cheaper to use.
 
session88 said:
The way I read Table 400.5(A)(2) I will need 3/0 Four Conductor Flexable Cable from the Outdoor Portable Gen. to the new Inlet Pin & Sleeve Receptacle. Is that correct or is there an exception allowing for smaller Flexable Cable ?
Click to expand...
The language in 110.14(C)(1) "shall be based on Table 310.16 as appropriately modified by 310.12." has always made be avoid the tables such as in 400.5.
 
Ok I will use Tabe 400.5(A)(2) to size the flexible cord between Temp. Portable Gen. and building.

Good point with the Camlocks. We have always use Pin & Sleeve type (Appleton Powertite or similar) connectors for our Temp. Gen. connections, but I have seen and CAT, Kohler and other Gen. companies us the Camlocks for Temp. and Permanent installations. I will get $pricing$ for a set of Camlock plugs and receptacles to compare against the super high cost of the Pin & Sleeve equipment. Thanks for the recommendations.
 
FWIW, I usually get Camlok stuff from Trystar in Minnesota, and usually as pre-assembled units (e.g. a set of 5 female cam's on 10' 1/0 copper cable).

Also, if you use P&S, you'll need to keep spares of them or maybe be un-powered if there's a problem.
 
110.14 deals with connections, and (C)(1) applies to the termination temperature ratings and how that affects ampacity, it also contains the magic words "Unless the equipment is listed and marked other‐wise". And check out (1)(b), there.

You will also find that types W and SC are often prominently marked on the jacket to use Table 400.5, and that's on the spec sheets. If the jacket of the listed cable says to use 400.5 for ampacity, I will. (You still have to pay attention to termination temperature, but 315.16 probably won't be relevant.)
 
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