Breakers and Enclosures for adding a Second Classic 150 to an E-Panel

[keithwhare]

I'm involved with a clinic in Haiti (www.healingartmissions.org). In 2010, we installed 1560 watts of PV panels (130 watt, 3 strings of 4 panels), a Magnum MS4024 inverter, an Outbox FM60 charge controller, and a MidNite Solar E-panel for the MS4024, and a 24volt battery bank (12 Trojan T105s, 3 strings of 4 batteries).

We are working on expanding the system. The current plan is:

• Replace the Outback charge controller with one Classic 150
• Add eight 300 watt PV panels (RPSG-300W-PE) in four strings of two panels plus a combiner box
• Add a second Classic 150 for the 2400 watts of new panels
• Whiz bang Jr.
• Replace the battery bank with 8 Trojan L16H-AC 6 volt batteries in two strings of four batteries

There is no room in the existing e-panel for the input and output breakers for the second Classic 150 so we need to put the breakers in a separate enclosure.

According to the Classic Sizing tool for these PV panels:

• Rated PV Array Current: 32.88 Amps
• Battery Charging Current @ 28.8V:  83.3 Amps

I'm planning on using #4 wires from the combiner box to breaker to Classic 150 to breaker into the e-panel and keeping the runs as short as possible within the available wall space.

For the Classic 150 input, a 40 amp or 50 amp breaker should be ok.
For the  Classic 150 output, we need a 100 amp breaker.

For space and neatness, I would like to use one box for both breakers. I have figured out two possibilities:

• DIN Rail Mount breakers (MNEPV-50 and MNEPV-100) and a Big Baby Box Enclosure
• Panel mount breakers ( MNEDC-50 and MNEDC-100) and a MNEDCQUAD enclosure for panel mount breakers

Any opinions on which option would be better for this application?

Thanks
Keith

[keithwhare]

Here's a picture of the current installation:

[keithwhare]

Here's a picture of the inside of the e-panel.

[Westbranch]

Keith, I don't know if you are aware that the E Panels are mirror images on both sides....  I know as I got a right hand panel and had the reverse it to left hand to work in the area I had to mount it in.
So yes the large CB could be mounted on one side or the other.  It might take some rewiring but it may be possible...  alternatively get another E-panel?

[keithwhare]

Westbranch,

Replacing the existing Outback FM60 with a Classic 150 will be easy.

This issue is adding a second Classic 150 to an existing E-panel. I am not at all sure there is enough room to add the breakers for the second Classic 150 to the E-panel.

If I could get another DIN rail mount bracket, I might still have room on the upper right side of the e-panel to add the bracket and the breakers I need. I don't have a good picture of the right side, so I can't tell of there is still enough space above the conduit we added there.

Keith

[Vic]

Hi Keith,

Am not very familiar with e-panels.

Things might get very busy if you added an additional breaker bracket.

The idea of using a BigBaby or DC Quad box seems like it should be fine,   if you have some room on the wall for the additional Classic and the new box.

The DC Quad is a bit roomier,   and a 100 A Panel Mount breaker occupies only a single slot,  verses two spaces for the MNEPV DIN 80 and 100 A breakers.   But as you know,   the PM breakers have studs for connections,   and therefore require good crimps on the cable lugs.

As an aside,  it is possible that the new 2400 W of PVs on a 24 V system  will be running that Classic a  bit hard.

Was unable to find the PV modules for the 2400 w addition,   but made up some numbers and ran them through the Classic String Sizer.   It does say that 0.9 Classics would be required.

Obviously,  you might have the FM60 that was removed,   as a backup,  if the Classic protested too much.

Your budget may not be very large,   so,  the Classic on the 2400 w array  can take care of itself without sepending added funds on any more hardware  ...

Sounds like you and your associates are doing good work in Haiti.

Good Luck,   Vic

[Westbranch]

Hi Keith, I see what you mean if you are hoping to ''drop in'' one of the Classics where the FM is...  you would have to mount the 2 Classics  separately , on the wall, and use longer cables to and from the E-panel....

I saw a clean install of 2 Classics done that way, side by side, several (~4+) inches apart, with a 'gutter' below to encase the wiring.. If I can find it I will link it ...

I was pondering all the connections and went to MN Documents and found this.

http://www.midnitesolar.com/pdfs/MNEMS4024PAE-2CL150-REVB.pdf

They have very craft-fully avoided your question and issue of using 2 Classics on one E-panel...  you can see the E-panel on its back with the 4024 above it, dead center of the schematic...

They must have a solution in mind if they did all the schematics....  A call to tech support may get you the answer...

[Halfcrazy]

On a 120 volt Magnum E-Panel you have 3 MNEDC spots on the top right, we use 2 of those for MNEDC100 breakers for the battery of each classic. On the left side you have a spot that holds several MNEPV breakers and this is where you would put the 2 PV input breakers. I know now you have a GFP breaker in there but that goes away with Classics.

[keithwhare]

The E-panel we have (MNE250STM-L in 2010) does not have a DIN rail bracket on the top right. Is there a part number for just a bracket?

Also, we punched a couple of holes in the plate on the right side. The top hole which would impact the breaker if we had a bracket for the breaker. Is it possible to get a replacement plate?

Keith

[keithwhare]

On a 120 volt Magnum E-Panel you have 3 MNEDC spots on the top right, we use 2 of those for MNEDC100 breakers for the battery of each classic. On the left side you have a spot that holds several MNEPV breakers and this is where you would put the 2 PV input breakers. I know now you have a GFP breaker in there but that goes away with Classics.

It took me a while, but now I understand what you are saying. It also helped that I found a picture that shows the upper right side of the e-panel.

Thanks
Keith

[Westbranch]

On my e-panels I have a manual bypass switch in that upper right location (from factory)

[keithwhare]

On my e-panels I have a manual bypass switch in that upper right location (from factory)

This E-panel has the manual bypass switch on the upper left side. See the picture below.

The changes we need to make to to support two Classic 150s are:

• Add two MNEDC-100 panel mount breakers on the upper right side
• Use the existing two 63 amp breakers for the two array inputs
• Take the 63 amp ground fault protector out of the circuit but leave in place to fill the open slots

The pieces are falling into place, at least in my head.

Keith

[Halfcrazy]

On my e-panels I have a manual bypass switch in that upper right location (from factory)

In your case the breaker locations would be on the left side. Basically the panel mount breakers are on the opposite side than the bypass

[Westbranch]

thanks for the comment Ryan, Yes that, opposite sides, is how I rearranged them..