Difference between MHF and quadruplex URD

[ridgepatrol]

Hello, I need to run an underground cable to my detached garage.

The distance is about 500 ft.

Can someone educate me on the differences between MHF aluminum cable and quadruplex URD aluminum cable.

For the same size of wire (2/0-2/0-2/0-1), the MHF is close to $3/ft, while the quadruplex is $2.11/ft. So there is a significant savings when using the quadruplex.

I will be getting an electrician to do the final connections, but I will be handling the purchase of the cable and the burial of it.

What are the advantages/disadvantages to either cable?



Thanks,
Matt.

 

[brewchief]

Most URD doesn't carry the ratings needed to be run inside of a building, if your application would have both ends terminated outside and a different wire running inside the building then it could be used.

Sent from my SM-G965U using Tapatalk

 

[wyliesdiesels]

Insulation rating is the big difference.

As said above, single rated URD is not permitted for use indoors regardless if its in conduit.

Post a link to the wire you are looking at

 

[ard]

Grand Bend Ontario

Not sure of the rules up there....

Saving $400 on cable, but then paying for two boxes, connectors, fittings and electrician labor.... might not be that significant

Out of curiosity, you running a 60Amp service?

 

[ridgepatrol]

This is the wire that I am looking at:
https://www.nassaunationalcable.com/2-0-qaudruplex.html

I will be using a 50 amp double pole breaker in my main panel, as I have two slots left in the panel, and to go any larger will require a four slot breaker, which would require rearranging some of the circuits.

I realize that if I was to utilize all 50 amps, that I would be at the edge of the acceptable voltage drop of 5%.

I have done the load calcs, and I don't believe I will be much over 20 amps for any sustained period of time, so for the most part the voltage drop should only be 2%.

 

[ard]

This is the wire that I am looking at:
https://www.nassaunationalcable.com/2-0-qaudruplex.html

I will be using a 50 amp double pole breaker in my main panel, as I have two slots left in the panel, and to go any larger will require a four slot breaker, which would require rearranging some of the circuits.

I realize that if I was to utilize all 50 amps, that I would be at the edge of the acceptable voltage drop of 5%.

I have done the load calcs, and I don't believe I will be much over 20 amps for any sustained period of time, so for the most part the voltage drop should only be 2%.

I use 3%, which is generally recommended in the US.

I ran a quick calc before my post...2/0 AL @60A is good to 550 feet BUT WITH COPPER. (So my bad)

AL is good to 442 @ 50. Kinda on the edge, but fine IMO. (At 40 you are back to 550.)

So sounds good.

 

[Bert_]

Just because you put a certain size breaker doesn't mean you automatically pull that much load. A little more voltage drop for a few minutes once in a while isn't an issue.

 

[ridgepatrol]

I am having a hard time sourcing a 2/0-2/0-2/0-1 wire spool that is over 500ft long.

The bigbox stores all sell spools of 500ft in that size, and are unable to order a custom length.

My distance is 478ft, but I want to make sure I have 10% extra, so that I don't end up short, so say 550ft.

Is there a variation of the 2/0 MHF that I could use ?

I have seen 2/0-2/0-1-4 MHF that can be ordered in the length I need.

I am not sure how that relates to the voltage drop and amp load over a distance of 550ft.

Can someone school me on whether all of the conductors have to be the same gauge, and what the minimum gauge of the ground can be?

 

[wyliesdiesels]

I am having a hard time sourcing a 2/0-2/0-2/0-1 wire spool that is over 500ft long.

The bigbox stores all sell spools of 500ft in that size, and are unable to order a custom length.

My distance is 478ft, but I want to make sure I have 10% extra, so that I don't end up short, so say 550ft.

Is there a variation of the 2/0 MHF that I could use ?

I have seen 2/0-2/0-1-4 MHF that can be ordered in the length I need.

I am not sure how that relates to the voltage drop and amp load over a distance of 550ft.

Can someone school me on whether all of the conductors have to be the same gauge, and what the minimum gauge of the ground can be?

Have you tried these guys?

They do custom lengths upto 1500’

https://www.wireandcableyourway.com/2-0-2-0-1-4-aluminum-mobile-home-feeder-cable.html

 

[theoldwizard1]

Most MHF uses the same insulator as XHHW. Not sure about URD.

 

[Bert_]

I am having a hard time sourcing a 2/0-2/0-2/0-1 wire spool that is over 500ft long.

The bigbox stores all sell spools of 500ft in that size, and are unable to order a custom length.

My distance is 478ft, but I want to make sure I have 10% extra, so that I don't end up short, so say 550ft.

Is there a variation of the 2/0 MHF that I could use ?

I have seen 2/0-2/0-1-4 MHF that can be ordered in the length I need.

I am not sure how that relates to the voltage drop and amp load over a distance of 550ft.

Can someone school me on whether all of the conductors have to be the same gauge, and what the minimum gauge of the ground can be?

I've never had a problem getting longer lengths. 1000-1500' rolls are common. I think the big rolls that my electrical supply makes cuts from are 2500'

Normally the ground would be #8 aluminum for 30-60 amps. But you up sized the wire for voltage drop so the ground needs to be bigger also
----
I did the calc. Looks like you want min #3 Al for ground

You could get a 3 wire cable and add a #3 or #2 USE wire in the trench for your ground. Not sure if that would save much. And I'm not sure of the rating on USE

 

[mike93lx]

Undersizing the neutral and ground is fine. Your 120v loads will likely be relatively close to balanced anyway, but just pay attention to how the panel is laid out. Easy enough to. Move a breaker up or down a space.

2/0-2/0-1-4 would be fine.

I wouldnt bother with URD for $100-200 difference. I would much rather have a simple LB on the outside of my building than a big junction box, let alone dealing with the connectors.

Will your 50a breaker accept 2/0? If not, you'll have to transition to smaller wire, which might swing it towards URD anyway

 

[ridgepatrol]

Thanks for all of the feedback.

I have found a vendor that will sell me a 600ft spool of 4/0-4/0-2/0-4 for $0.10 per foot more then 2/0-2/0-2/0-1, which only can be ordered in a 500ft spool, which won't work for me.

If I go with this vendor, will the two 4/0 hot wires be a benefit to me, since the neutral is the same size as the other?

 

[mike93lx]

Thanks for all of the feedback.

I have found a vendor that will sell me a 600ft spool of 4/0-4/0-2/0-4 for $0.10 per foot more then 2/0-2/0-2/0-1, which only can be ordered in a 500ft spool, which won't work for me.

If I go with this vendor, will the two 4/0 hot wires be a benefit to me, since the neutral is the same size as the other?

There is no chance that is fitting in a 50a breaker. Although I don't think 2/0 was going to fit either. What breaker size are you using in the shop? It would help to make sure you get something that will fit the wire size and then you only have to transition to smaller at the main panel.

If you oversize the hot conductors, it requires up sizing the neutral and ground. A sparky can confirm for sure

 

[ard]

A Canadian sparky can confirm for sure

OP is up north....

 

[ridgepatrol]

The subpanel main breaker is a 100amp Siemens, I am not sure of the largest wire size that it will accomodate, so I may have to transition to a smaller wire.

I realize I will for sure have to transition to a smaller wire at the main panel, as the 50 amp breaker will only accommodate up to a 4 awg size wire.

Will having 4/0 for the two hots, and 2/0 for the neutral, cause less voltage drop at 120v than the other cable that has 2/0 for all three wires?

 

[pattenp]

Most MHF uses the same insulator as XHHW. Not sure about URD.

The only thing the same about the insulation on MHF, URD, XHHW is the basic structure is cross linked polyethylene (XLP). The ratings of the insulation on each are different.

 

[ridgepatrol]

The Siemens main breaker on the subpanel will accept a 2/0 size wire, so I am now thinking that it would be easiest to use 2/0-2/0-1/-4 size MHF wire as mike93lx suggested. I can get this size wire in the length I need.

My 120v regular loads will mostly be led lights, infloor heat with gas water heater, and a small fridge, so they should be below 20 amps total, and I would still have the second hot wire for an additional 20 amps, with 3% voltage drop.

I don't have any 240v tools/appliances at this point, but the 2/0 would give me 40 amps of power at just over 3% voltage drop.

This shop is really just a 2.5 car garage, with a loft, and I don't plan on having any large electric tools. Mostly just hand tools and rechargeable power tools.

Do my calculations make sense for this, what are other's thoughts on this ?