Author Topic: (2) MNEPV100 mounted in big baby, clearance problem  (Read 652 times)

daloniga

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(2) MNEPV100 mounted in big baby, clearance problem
« on: December 04, 2016, 10:37:29 PM »
I've got a pair of MNEPV100's mounted in a big baby.  The left most breaker is pretty much a straight shot thru the left most 1" conduit.  The right-hand breaker is in a position that requires a super-tight turn as it does not align with either 1" conduit.  Four gauge THHN does not like very tight turns.

The breakers have a 1-into-2 vertical metal adapter to transition the input into both haves of the input breaker.   Does anyone make a 90 degree 1-into-2 adapter for these breakers?  If not, what metal would be suitable for a local machine shop to make a 90 degree adapter?  Maybe some stainless steel variant?  Something else?



TomW

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Re: (2) MNEPV100 mounted in big baby, clearance problem
« Reply #1 on: December 05, 2016, 09:13:54 AM »
Daloniga;

Maybe a chunk of copper bus bar from an old breaker panel? Stainless would likely work and perhaps be an easier material to source.

Any chance you can cheat the conduit hole off to one side ? I keep a largish step bit for just such issues so I can cut a hole in a different spot or make it bigger. Might not work if you already popped the slug out?

Perhaps you can hog out the hole and go up a size on the conduit at the hole to get it to fit?

Just tossing stuff on the wall to see what sticks.

Tom
« Last Edit: December 05, 2016, 03:48:05 PM by TomW »
Do NOT mistake me for any kind of "expert".

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Vic

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Re: (2) MNEPV100 mounted in big baby, clearance problem
« Reply #2 on: December 05, 2016, 02:49:45 PM »
Hi daloniga,

Have you looked at the docs for the BigBaby box?   It is rated for a Max wire size of #6 AWG.   It is a tight space for four breakers (ie,  two 80 or 100 A DIN breakers),  even with #6 cable.
Here is the Brochure for the Small Enclosures:
http://www.midnitesolar.com/pdfs/smallEnclosure_front-back.pdf

Realize,  that you now have the BB box and the double-wide breakers,  but,   the DC Quad box can accommodate single wide 100 A breakers,  and #4 AWG maximum cable size ...   yea,  I know ...

Stainless is not a very good conductor of current or heat,  so,  would not change the copper connector that parallels the ins and outs of the 100 A breakers,  but do know that you are trying to make the hardware that you now have work.

You might be able to save yourself a bit of grief,  if the BB box is quite close to the CC/s,  if you used a short #6 AWG cable into the breaker/s,  and #4 AWG out of them.   Assume that you may be using two Classics,  each with a 100 A battery breaker?

FWIW,   Good luck,   Vic
Off Grid - Two systems -- 4 SW+ 5548s, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 3X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  Thanks MN for Great Products/Service/Support!

JazzyJoelPro

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Re: (2) MNEPV100 mounted in big baby, clearance problem
« Reply #3 on: May 03, 2018, 09:28:44 PM »
Seems that all of midnight solar enclosures have wire size issues!!
Per nec there is not the neccessary space to fit (4) #4 awg in their classic150 the quad box is very unsafe to have (8) #4awg wires.... not to mention with breakers mounted you can NOT safely work on system with out risk of case gounding ....

KyleM

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Re: (2) MNEPV100 mounted in big baby, clearance problem
« Reply #4 on: May 04, 2018, 11:20:11 AM »
While it says clearly on our BigBaby specifications  Max. Wire - breakers 6 AWG

It takes a little bit of gentle massaging and a little bit of thought, but I was able to get 4AWG into my display Big Baby without having any sharp bends.

I connected the wire to the breaker then snapped the breaker into place. This gives you a bit more leverage to make the wire go where you want it.  Also remember the warmer the wire is the more pliant it becomes. A few seconds under the heat gun for shrink wrap and a little bit of leverage and it went right in.

I hope this helps.

Kyle

FNG

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Re: (2) MNEPV100 mounted in big baby, clearance problem
« Reply #5 on: May 04, 2018, 05:09:02 PM »
I might suggest not heating the insulation up, NEC dictates bending space for a reason, If you bend in a sharper radius or heat the insulation and bend the wire you will stretch the insulation and possibly damage it. If the insulation is made thinner it no longer carries its same insulative properties. Long story short, The big baby was never designed for #4 wire or the MNEPV100 breaker. For that large a wire I would look into a Mini DC