Generator AC output wiring

[Perdiem]

I am installing a used Northern Lights 673 6kw generator. 6kw at 120 volts works out to 50 amps and that's the size of the breaker I have on the generator side of the gen / shore power switch. That means 6 gauge wire and that's what was run to the old 7.5 Onan but it is very stiff. My plan was to put a terminal strip near the generator and tie down the existing wires to one side and continue on with new more flexible cable.

My problem is - and I thought this when I first laid eyes on the generator - the control box is very crowded and there's not much room for 3 #6 wires. Would it be permissible to run two 10/3 cables for the short distance (~6 ft) to the terminal strip? It's about 15 ft the rest of the way to the panel.

#6 is 26251 CMs and 2 x #6 is 20766 or the equivalent of a #7 wire.

[Manateeman]

I’m confused as to the plan but concerned about the condition of the wire.
The condition of the insulation is very important. Some cable is stiffer than others but I’ve seen cable exposure to heat, oil or diesel turn stiff which in some cases means the protection is compromised.
If you can post some photos or a little hand drawn diagram, I’m sure it will help.
Happy trails to you.
Mark and the manatees

[smac999]

no 10/3 is for 30a. (sorry just noticed you said two of them, but still no)

6awg marine wire is very flexible

make sure you have a breaker on the output of the gen. either internal or directly outside it

and make sure the ground and neutral get connected together inside the gen if it does not come with it pre jumpered.

[GordMay]

Originally Posted by Perdiem

... Would it be permissible to run two 10/3 cables for the short distance (~6 ft) to the terminal strip?...
... #6 is 26251 CMs and 2 x #6 is 20766 or the equivalent of a #7 wire.

Not under the National Electrical Code (North America).
NEC Section 310.4 permits conductors that are at least 1/0 AWG or larger to be connected in parallel, if these parallel conductors are electrically joined at both ends to form a single conductor, where the circular-mil areas of these conductors are added together, to provide the total cross-sectional area, for the overall size of the parallel conductors (as you’ve calculated).
All of the paralleled conductors, in each phase, neutral or grounded set, must be the same length and be made from the same conductor material. They must be the same circular mil area and have the same type of insulation.
There are exceptions to this (1/0 min), which don’t apply to your application.

[oleman]

AWG 6 ANCOR marine wire is not very rigid.

Could be a good opportunity to upgrade your wiring.
My opinion is based on Ancor PN 111910 which is AWG 8 but 6 is very similar.

[Cadence]

Originally Posted by GordMay

Not under the National Electrical Code (North America).
NEC Section 310.4 permits conductors that are at least 1/0 AWG or larger to be connected in parallel, if these parallel conductors are electrically joined at both ends to form a single conductor, where the circular-mil areas of these conductors are added together, to provide the total cross-sectional area, for the overall size of the parallel conductors (as you’ve calculated).
All of the paralleled conductors, in each phase, neutral or grounded set, must be the same length and be made from the same conductor material. They must be the same circular mil area and have the same type of insulation.
There are exceptions to this (1/0 min), which don’t apply to your application.

Is the NEC still published in a little book with yellow covers?

[GordMay]

Originally Posted by oleman

AWG 6 ANCOR marine wire is not very rigid...

Indeed.


What you want to use is tinned copper boat cable, with type 3 stranding (or class K or M).
I recommend wire and cables by Pacer Group or Ancor Products (but there are others):
Pacer ➥ https://www.pacergroup.net/
Ancor ➥ https://www.ancorproducts.com/en
Genuine Deals ➥ https://www.genuinedealz.com/ (made by Pacer),

An excellent explanation, all about UL 1426 Boat Cable, BC 5W2.
Boat cable ~ Ocean Navigator
➥ https://www.oceannavigator.com/boat-cable/

[Perdiem]

Thanks guys - I kind of figured as much about using 2 x #10 instead of a #6. Just to be clear, the boat's existing wiring is old nonmarine 6/3 that is fairly stiff due to having fewer strands. The insulation is still good and the copper is still shiny when I remove the insulation (obviously not tinned).

I am using new Ancor 6/3 to go from the terminal strip into the generator and I am still at a loss to see how those three big wires will fit into the control box and tie down on the #10 screws.

I will look at a friend's this week and see how they did it. It is a 5kw so probably #8 wires but it will be similar.
Gregg