Inlet box to transfer switch cable

[89GLH]

Bought a 7000 watt generator, 30 amp Generac. Am I correct in assuming I can run 10/4 SOOW cable the 60' from the back of my house (where the plug will be) to the transfer switch in the basement? It looks like the same cabe provided to plug the generator into the inlet box.

 

[mobiledynamics]

Portable Cord is not mean to be in permanent installation.

Run conduit or Romex/etc to the transfer switch

 

[89GLH]

Then why have I seen folks use it over conduit? Does it break down over time? Just curious. Specs say minimum 10/4. Would the same cable used to wire my heat pump be enough? The 10/3 UF-B?

 

[rockwithjason]

because it's cheap and easy. it's the lazy man's install. flexible cord is not allowed to be used in place of other wiring methods for permanent installs with VERY few exceptions

 

[kd3pc]

Mom says, "and if every other kid in your class does XYZ, are you going to do it too??!!??"

Use does not indicate safety, appropriate for the job, long lasting, etc.

SO use in this case is not to code...code is there to protect things and prevent fires. SO is primarily used for "portable" applications

The jacketing is not designed for the intended use, as Mobile pointed out. Subject to cuts, abrasions, UV degradation, lawn mowers, kids, etc, etc. The conductors are generally stranded, subject to water intrusion and corrosion, especially when incorrect connectors are used.

Your house, your system, and if your AHJ is never around it may last a year or so. With #10 SO, I would be more concerned about voltage drop at full load.

 

[Hpozzuoli]

You should only use a cord to your inlet box. The rest should be in conduit. My pic shows how I use the cord to the inlet and conduit from the inlet to my panel. I use an interlock vs a transfer panel just because I want everything available and not just certain things.

 

[mobiledynamics]

For the sparks out here, I don't think it will produce a full 30 .
With that said, when do you upsize to 8 - what is the maximum length run cumulative of gen-inlet-transfer for a 30 amp run before you upsize

 

[89GLH]

What would a safe recommendation be for a 60' run to the transfer switch? I may rethink the length of the run, only reason it's that far is to keep it in the back yard where it would take more effort to make off with it (if one were to try and steal it).

 

[48RON54]

Why not test it? I don't think 60' is going to give you much of a voltage drop. The best way to find out would be to connect the generator where you originally intended to place it and put some load on it. I'm sure someone has some formula for how many feet equals how much voltage drop at how many amps and blah, blah, blah........ I would just do a real world test.

 

[89GLH]

My parents had theirs installed by a local company that used the same cable as the gen to inlet box cable, and it's been secured in their drop ceiling for the past 20 years. Granted theirs only runs about 30', I don't see how that makes a huge difference.

 

[48RON54]

I am used to dealing with much larger generators where you have some minor voltage adjustment abilities at the control panel.....I'm not sure if your has something like that or not.... If so, I would think any minor voltage drop from that run could be compensated for by adjusting voltage at the unit. BUT, i really don't think your 60' run is going to matter. A 100' run is very common on the larger units and I have even run 600'+ runs without any voltage issues.

 

[mobiledynamics]

My parents had theirs installed by a local company that used the same cable as the gen to inlet box cable, and it's been secured in their drop ceiling for the past 20 years. Granted theirs only runs about 30', I don't see how that makes a huge difference.

Portable cord is not meant for permanent installations

 

[kd3pc]

^^^^^ What he said

 

[kd3pc]

My parents had theirs installed by a local company that used the same cable as the gen to inlet box cable, and it's been secured in their drop ceiling for the past 20 years. Granted theirs only runs about 30', I don't see how that makes a huge difference.

for some reason, rodents love the taste of the SO jacket...almost as much as ham radio coax cable jacket....

SO especially not rated for drop ceilings or plenums, nor is it approved to be "secured" to drop ceiling components or to lay there.

best of luck

 

[Mustang51js]

Run a 10/3 romex from transfer switch and install a 30 amp twist lock gen plug on the outside of house where you plan on plugging it in,if you can run the romex where you want it.

 

[89GLH]

It's run through holes in the joists, not on the drop ceiling. LOL, what if I run it through conduit?

 

[Mustang51js]

You can run the romex through the holes in joist,no need for the conduit unless you think it can get damaged if something hits it

 

[mrobins297aaa]

I doubt you'd have much problem with voltage drop at 60'.

mine was 140' feet from the outdoor plug to the panel so i up sized it to 8-3/wg and it works fine. ( i have the generac gp7500e)

why would you want to use so cord when regular romax 10-3/wg would be cheaper?
put the plug outside and run romax to your panel/transfer switch.

 

[mobiledynamics]

Portable Cord is in free *air*. Run THHN in the conduit

 

[rockwithjason]

My parents had theirs installed by a local company that used the same cable as the gen to inlet box cable, and it's been secured in their drop ceiling for the past 20 years. Granted theirs only runs about 30', I don't see how that makes a huge difference.

If that is true then your folks should find the rat bastards, kick the hell out of them and get their money back because so in the ceiling was illegal 20 years ago too

 

[48RON54]

Run a 10/3 romex from transfer switch and install a 30 amp twist lock gen plug on the outside of house where you plan on plugging it in,if you can run the romex where you want it.

I like this guys twist lock idea

 

[pattenp]

I believe you said you have a 30A power inlet. As Mustang has suggested, use (Romex) NM-b 10-3 from power inlet to transfer switch.

 

[wyliesdiesels]

For the sparks out here, I don't think it will produce a full 30 .
With that said, when do you upsize to 8 - what is the maximum length run cumulative of gen-inlet-transfer for a 30 amp run before you upsize

What would a safe recommendation be for a 60' run to the transfer switch? I may rethink the length of the run, only reason it's that far is to keep it in the back yard where it would take more effort to make off with it (if one were to try and steal it).

Why not test it? I don't think 60' is going to give you much of a voltage drop. The best way to find out would be to connect the generator where you originally intended to place it and put some load on it. I'm sure someone has some formula for how many feet equals how much voltage drop at how many amps and blah, blah, blah........ I would just do a real world test.

I am used to dealing with much larger generators where you have some minor voltage adjustment abilities at the control panel.....I'm not sure if your has something like that or not.... If so, I would think any minor voltage drop from that run could be compensated for by adjusting voltage at the unit. BUT, i really don't think your 60' run is going to matter. A 100' run is very common on the larger units and I have even run 600'+ runs without any voltage issues.

For u inquisitive minds:

Wire size formula:

K= 12.9 for CU and 21.2 for AL
L= length
A= max amps of branch circuit
VD= desired voltage drop

Formula:

2*k*L*A/VD

2*12.9*60*30/7.2(3% of 240v)=6,450 circular mils

U then check your handy dandy circular mils wire size chart. Obviously if the ampacity of the resultant wire size is less than the circuit ampacity, then u must upsize yor wire. In this case, u would upsize because 10,383 is the size of #10.

To figure voltage drop for a given size of wire, u change the voltage drop value to the circular mils spec of the gauge of wire in question. Simple!

 

[LS6 Tommy]

Run 10/3 NM-b inside as previously described. It's the correct way & it's also much cheaper than SOOW...

Tommy

 

[Mustang51js]

I like this guys twist lock idea

If you look at the pic in post 6 has the twist lock made for generators,it's a male plug to plug the cord into. The little gray box, about $50

 

[LS6 Tommy]

Plug, connector & inlet box are NEMA L14-30.

Tommy

 

[Charles (in GA)]

Put the inlet box on the outside of the house, somewhere reasonably out of the weather (even it if is weather resistant) and use the SOOW cord to get the generator away from the house (for noise reasons) and use Romex type jacketed cable in the house from the permanently mounted inlet box to the transfer switch.

Indeed the generator will have a female L14-30 receptacle on it, your cord will need male and female L14-30 plug and connectors, and this will mate to the inlet box.

I used 8/4 SOOW because that is what I found on Craigslist for cheap. Two pieces, one about 37 ft, the other was about 48 ft. Bought plugs and connectors (technical term for the female end on the cord) off of Ebay. 4 ea male P&S plugs in retail packaging for $25 and two Bryant connectors for $10 each, all included shipping.

Charles

 

[Mustang51js]

A good deal for a cord is actually at Home Depot, they sell the generac 30 amp cords for $60 and it's 25 foot premolded cord. Which is a good deal considering the 30 amp female cord end plug is around $50 by itself.

 

[mobiledynamics]

I always prefer to make my own portable cords using Carol SOOW cord. Tons better in flexibililty, etc. Hubbell ends are a must

 

[89GLH]

The transfer switch came with the cord to plug the generator into the inlet box. 10/3 is only 3 wire though, no ground. Unless the generator basically is like running a compressor back into the transfer switch, 240v only (hot, hot, neutral)? Clearly says minimum 10/4.

Is the 4th plug not used? The only 10/4 I see is SOOW cable.

 

[pattenp]

You are to use a 4 prong plug and 4 wire cord. The ground is needed.

 

[Mustang51js]

The transfer switch came with the cord to plug the generator into the inlet box. 10/3 is only 3 wire though, no ground. Unless the generator basically is like running a compressor back into the transfer switch, 240v only (hot, hot, neutral)? Clearly says minimum 10/4.

Is the 4th plug not used? The only 10/4 I see is SOOW cable.

Not sure if your talking about romex in the beginning, 10/3 romex is actually 4 wire but they don't count the ground. The rubber cord counts all wires when labeled.

 

[89GLH]

Does the uncovered gound make a difference, or should I pull a seperate covered ground with 10-3?

 

[pattenp]

You need to make clear to us what the 10-3 is. Is it cord or romex? Romex will have a bare ground, cord will have insulated ground. Romex with 4 conductors will be listed as 3 w/ground. Cord will be listed as 4. In either case you can not add an additional conductor to a circuit that is not part of the cable assembly. The only way to have individual conductors it to use conduit with individual THHN wires.

Does the uncovered gound make a difference, or should I pull a seperate covered ground with 10-3?

 

[gatchel]

Edit. Wrong topic

 

[89GLH]

I see, pattenp. Looking more into it I may just use 10-3 MC, since all 4 wired are coated.