Trailer - Disable PIP for long term storage

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OffGridInTheCity

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I'm converting a cargo trailer to a camper. The electrical system will have a PIP 48v@3000w. I'm trying to wire this up with an option tobypass the PIP for long term storage - e.g. leave the trailer load center energized without involving the PIP.

This is 120v @ 30a circuit - with Load (black), Neutral(white), and Grd (green).

I'm thinking of using a DPDT 120v 30a switch (https://www.gordonelectricsupply.co...2pC1UpV4IV1kDXQBGMMyHEJ30kw7EoYBoCpVEQAvD_BwE )to toggle the Load (black) to switch thru or around the PIP and wondering if this sounds OK to you-all. The Neutrals would all be hooked together and I don't think it would affect the PIP as long as the Load wire is disconnected. Here's a drawing:

image_jzwerc.jpg


In operation I would flip the switch up (and turn on the PIP) to use the PIP - and flip the switch down (and turn off the PIP) to bypass it.

FYI -Cargo Trailer pic in progress...

image_iyuvdd.jpg
 

daromer

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Im pretty sure you need to switch both neutral and the phase. The neutral is freeflowing inside their inverters or atleast should be in most of them. They even have a larmcode for neutral grounding issues.

Thats why i had to go for 5 wire setup instead of 4 ie separate ground from neutral so i could switch 4 wires instead of 3 in the ATS.

Just get a 2 pole 1-0-2 switch. You can even have a manual one in your case. Or actually in your case you need a 3 pole 1-0-2 switch.
 

OffGridInTheCity

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Excellent - thanks for the warning and pointing me to 'changeover' switching...https://www.amazon.com/gp/product/B07SQP3YRG/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1 This should work :)

image_gyrttv.jpg
 

daromer

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Yes that work. And unless you need to switch often and by precise timings a switch like that works great. I use that on many places.

Why i state 1-0-2 is that they mechanically cant engage both sources at the same time and therefore not cause short. The 1-2 can potentially cause a short if we talk good practice and safety.

The 1-0-2 exist in many sizes so you will most likely find one that suits both switching and turning the PIP on and off.
With that said you migh want to be able to switch the PIP on before switching the load so you can do a close to 0-offline switch.
 

OffGridInTheCity

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I got my 3-position, 16-way switch and tried to put it in place today. It was a struggle with4 sets of 10 AWG wire tobend it all into the little greyenclosure .

image_sbgvfo.jpg


I did get it in (after much struggle)and it mostly workedbut then.... the PIP Out -> Main Panelfailed as only 1 wire had continuity!
Notice I broke out a piece of blue plastic and this caused #16 to have a gap / not make contact. Sigh - had to take it out and order another one.

image_eaucik.jpg


That's the way it goes for me - usually have to do things twice! Just thought I'd share as I'm sure I'm not the only one that doesn't alwaysget things working the first try :)
 

OffGridInTheCity

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Its working! Hopefully things will stay in place one this trailer starts bouncing along the road but for today, couldn't be more excited.
The battery bank (14s88p - 260ah - 13.5kwh)
1608315780908.png

The control closet - Gid/PIP selector, Combiner+Batrium, ATS (grid/gen), PIP, Shunts and Shunt-trip
1608315948167.png

Wiring Diagram
1608325579705.png

Grid/PIP Selector....
1608317178200.png
 
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OffGridInTheCity

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In the past, there was discussion on longmons reading different voltages. This is a brand-new install, first peak at longmons on 14s battery. Each pack was discharged via iCharger x8 to Storage (3.6v) - so all 14 packs should be identical. Notice that packs 1-12 are identical (per longmons) but packs 13 and 14 are showing a little higher... most likely due to longmon differences. Its a good 40mv difference. I say 40mv instead of 50mv because there's that 10mv back/forth with longmons.
1608317454686.png
 

daromer

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Dont forget to mount those batteries solid. Cant have anything that can move in rv :) So get some kind of things that holds them sturdy is my recomendation.
 

OffGridInTheCity

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Dont forget to mount those batteries solid. Cant have anything that can move in rv :) So get some kind of things that holds them sturdy is my recomendation.
Yes sir. They're sitting on 1/2 inch of foam (to absorb shock) with heat-pads underneath for cold weather. Large twist-ties hold each pack snug to foam/top-of-cabinet. I am wondering if the PIP and Batrium will be OK with the road shock... they survived shipping so why not? We'll see one of once I get this thing launched :)
 

daromer

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Batrium is not a problem since they are made to work in wehicles. The PIP on other hand may have loose caps. Would be good to open and hot glue the caps in place and such.
 

OffGridInTheCity

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Just got panels installed/hooked up on the cargo trailer - but the MPP is not charging at 'max amps' setting - e.g. at least 10a - as I would expect.

Any help setting this MPP up correctly (or at least understanding it) would be appreciated :)

Below you can see all the settings - I have 120v power AND PV power (133w) and the Max AC Charging current = 10a and Max Charging current = 20a. However, its only charging at 2a per MPP and 3.4a per Batrium.

I have Charger source priority set to "SLB&UCB" - which is "Solar energy for load first" and "Allow utility to charge battery" - so it seems like "Utility" would charge up to 10a at least?
1612908589103.png


Overall snap of activity....
1612909311077.png
 
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OffGridInTheCity

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I've discovered that charge current will go to 10a ("Max AC charging current" setting) if....

1) The PV array circuit breakers are turned off - the PIP thinks that Solar is no longer available.
or
2) The "Output source priority" is changed from Solar->Utility->Battery
1612990918580.png

to Utility->Solar-Battery
1612990713777.png


Makes no sense to me..... I don't see why Output settings affect/override "Charger source priority"...
1612990976810.png
 

daromer

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Then you struck the same things i have where i dont understand how they think and it isnt logic how it switches between things.
I cant help im afraid.
 

OffGridInTheCity

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Then you struck the same things i have where i dont understand how they think and it isnt logic how it switches between things.
I cant help im afraid.
Thanks for confirming! Looks like "Utility->Solar->Battery" will do what I need.
 

daromer

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On the MPI i have i have to set som unlogic time paramters to do what i want as example. And when going between winter and summer mode where in summer i want battery first and winter i want battery as reserve.. If i dont change like 10 parameters it either uses power from grid when i dont want to or battery when i dont want to.... As an example :D
 

OffGridInTheCity

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On the MPI i have i have to set som unlogic time paramters to do what i want as example. And when going between winter and summer mode where in summer i want battery first and winter i want battery as reserve.. If i dont change like 10 parameters it either uses power from grid when i dont want to or battery when i dont want to.... As an example :D
Yes. I have a few scenarios with the trailer and I just need to know what to set for different modes. For example:

1a) One mode is using the onboard generator to charge the batteries while driving - e.g. the generator goes to the ATS / PIP sees 'grid' and I want it to do the 20a max charging.
1b) An Alternate to this is just using the solar panels while driving to charge. The trailer is in shade so I can't test this very well right now - and surprised to see 2a charging (10a max) when when the panels only creating 100w in "Solar->Utility->Battery" mode. The 2a must be coming from the grid but why 2a instead of 10a?

2) Another mode is boondocking with sun and I want the solar panels to have priority - but maybe run the generator an hour or 2 to assist (with max amps flowing).

3) And bypass - where I have grid at a campsite (or just parked at the house) and bypass the PIP/batteries and leave it all turned off ---
*You're 3-position switch advice has solved this for me - thank you again for that!*

The good news is I can adjust parameters - but want to work out the minimum set of adjustments :)
 
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rahulmittal79

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I have Charger source priority set to "SLB&UCB" - which is "Solar energy for load first" and "Allow utility to charge battery" - so it seems like "Utility" would charge up to 10a at least?
 

OffGridInTheCity

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I have Charger source priority set to "SLB&UCB" - which is "Solar energy for load first" and "Allow utility to charge battery" - so it seems like "Utility" would charge up to 10a at least?
I agree - but changing this didn't make any difference - it stayed at 2.0a charge even with 10a+ max settings.
 

Rhettm_

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this is a very good project!

are there people about who can do jobs like this for people like me with no skills?
 
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