Electrical wiring help needed

[rubicon327]

Was going to PM tdf-Texas or Jon V but figured I would try this publicly first. Finally got around to the main 12V wiring upgrade. Replacing the existing 10AWG wiring with 6AWG and added a 60A Maxi fuse right near battery (see pic) and upgrading the battery disconnect switch to a 100A rated rotary style. So here is where I need assistance...

1. The existing auto reset fuse (see blue box on schematic) is only rated for 30A. If my upgraded Progressive Dynamics converter could theoretically put out 55A this seems way undersized. Should this be replaced with a higher amp rating or because I now how the 60A Maxi fuse at the battery could it be eliminated?

2. I currently have my main battery ground landed on a screw in an existing grounded metal junction box (see pic). The trouble I see is all the grounds to the frame are all small gauge. If I want to have the entire circuit be 6AWG to minimize voltage drop do I need to upgrade each of the grounds (see yellow lines on schematic) to a new ground lug(s) on the frame? Or is there a better way to wire the negative side?

3. The 120V AC ground bar in the power center has a very small gauge wire from the bar to the frame. Is the entire grounding of the 120V side dependent on this small wire? Seems this should be upgraded.

[tdf-texas]

Here's a wiring diagram for you. I will refer to this as we go.

Originally Posted by rubicon327

1. The existing auto reset fuse (see blue box on schematic) is only rated for 30A. If my upgraded Progressive Dynamics converter could theoretically put out 55A this seems way undersized. Should this be replaced with a higher amp rating or because I now how the 60A Maxi fuse at the battery could it be eliminated?
The 30A auto reset fuse is not needed. The 6 awg wire from the 60 amp fuse goes direct to the battery cutoff switch.

2. I currently have my main battery ground landed on a screw in an existing grounded metal junction box (see pic). The trouble I see is all the grounds to the frame are all small gauge. If I want to have the entire circuit be 6AWG to minimize voltage drop do I need to upgrade each of the grounds (see yellow lines on schematic) to a new ground lug(s) on the frame? Or is there a better way to wire the negative side?
The frame grounds should not used for the battery return paths. Only the trailer brake/stop/turn/running lights and brakes use the trailer frame as a negative return path.

The negative lug on the back of the WFCO is where your 6 awg negative wire should terminate.

The negative lug on the back of the WFCO is also where all the trailer device negative wiring is terminated and it has one wire connected to the trailer frame.

The other frame ground is in your 7-pin junction box and is shown in the diagram

3. The 120V AC ground bar in the power center has a very small gauge wire from the bar to the frame. Is the entire grounding of the 120V side dependent on this small wire? Seems this should be upgraded.
The ground on the WFCO AC panel is tied to the trailer frame for safety reasons - the only time the frame ground should have current passing through it is when an electrical fault has occurred - it normally does not carry any current. The hot (black) and neutral (white) wiring are what is carrying the 120V current.

[rubicon327]

Thanks Tom! A few clarifications needed...(by the way no solar, no inverter, no power tongue jack)

1. The 30A auto reset fuse is not needed. The 6 awg wire from the 60 amp fuse goes direct to the battery cutoff switch.

So it looks like I should ideally provide a new dedicated 12V+ power line from the lug of the disconnect switch to the breakaway switch. Then based on what you show I need to add a 40A thermal (auto reset) fuse on the 12V+ line coming in from the 7 pin. So my existing 30A auto reset fuse appears both undersized and wired improperly.

2. The frame grounds should not be used for the battery return paths. Only the trailer brake/stop/turn/running lights and brakes use the trailer frame as a negative return path.

Ok, understood.

The negative lug on the back of the WFCO is where your 6 awg negative wire should terminate.

Ok makes sense. Should I also upgrade the existing 10AWG wire from the WFCO DC board lug to the rear ground stud to 6AWG?

The negative lug on the back of the WFCO is also where all the trailer device negative wiring is terminated and it has one wire connected to the trailer frame.

Got it. Should the ground wire from the negative lug on back of the WFCO to the frame ideally be upgraded in size?

The other frame ground is in your 7-pin junction box and is shown in the diagram.

Understood. I will leave this ground line alone.

3.The ground on the WFCO AC panel is tied to the trailer frame for safety reasons - the only time the frame ground should have current passing through it is when an electrical fault has occurred - it normally does not carry any current. The hot (black) and neutral (white) wiring are what is carrying the 120V current.

Understood. Thanks.

[Greg A]

Interesting, Dave.
My 2015 has the metal junction box which I'm replacing, but the batteries are on the tongue the negative goes straight to a frame ground and positive comes inside to some type of fuse. My early guess is that the breakaway switch and the power tongue jack tie in there as well. It goes to the battery disconnect on the other side of that fuse, but no fuse between the battery disconnect and the WFCO like you show.
I'm not at the wiring yet, so haven't done a lot of tracing. Building the new lithium battery platform and equipment boards now and once those are completed and installed I'll be tackling the wiring.
I found a real nice 30a Inverter wiring diagram online that I'm adding to as I go and hopefully, will end up with a final wiring diagram for the front of the trailer.
I'll be watching your progress as ours appear similar in how they were setup.

[John in Santa Cruz]

mostly, the frame grounds the trailer lights and brakes to the truck. but it is tied to the battery negative for when the tug is charging the trailer during tow. other than that, there should not be any ground current from the battery+converter+solar to the chassis. oh, or the emergency brake, if the brake safety cable is pulled, then the trailer battery is being dumped into the trailer brakes and that return current will be via the chassis.

[rubicon327]

Originally Posted by rubicon327

So it looks like I should ideally provide a new dedicated 12V+ power line from the lug of the disconnect switch to the breakaway switch. Then based on what you show I need to add a 40A thermal (auto reset) fuse on the 12V+ line coming in from the 7 pin. So my existing 30A auto reset fuse appears both undersized and wired improperly.

Tom: I noticed you moved the 12V+ power to the breakaway switch to the battery side of the disconnect switch. Is this to ensure that the breakaway switch power from onboard battery cannot be turned off under any circumstances? Like forgetting to turn battery isolation switch back on before towing if it was off for storage. Oliver does not have a battery disconnect switch that I know of but they do tie the breakaway switch power in separate from the 12V charge line like you show to avoid it being subject to a failed/tripped 40A breaker. (Pink line in attached schematic)

[rubicon327]

Originally Posted by Greg A

Interesting, Dave.
My 2015 has the metal junction box which I'm replacing, but the batteries are on the tongue the negative goes straight to a frame ground and positive comes inside to some type of fuse. My early guess is that the breakaway switch and the power tongue jack tie in there as well. It goes to the battery disconnect on the other side of that fuse, but no fuse between the battery disconnect and the WFCO like you show.

Greg: I have the 7 pin junction box on order too but space is going to be tight for me with my mini-split refrigerant lines so close exiting the bottom of the trailer. Not going to be fun but should be a nice upgrade.

Honestly I think my 30A auto reset fuse was just wired wrong. If Escape had simply landed the battery positive and the wire leading to the WFCO DC board positive on the same terminal of the fuse it would have just been a pass thru. Then the 12V+ charge line would simply be landed on the other terminal. This would match Tom’s schematic and Oliver’s design and will be what I will be doing once I pick up a 40A auto reset fuse. (Quite confusing though because that would then leave all main wires completely unprotected. Probably why Escape has added fusing at the battery in more recent builds - which I now have with my 60A maxi fuse right at the battery)

This has been a fun learning experience so far. Get to play with a new hydraulic crimper and getting pretty good at shrink wrapping the connections.

[tdf-texas]

Answers are in red.

Originally Posted by rubicon327

Thanks Tom! A few clarifications needed...(by the way no solar, no inverter, no power tongue jack)

1. The 30A auto reset fuse is not needed. The 6 awg wire from the 60 amp fuse goes direct to the battery cutoff switch.

So it looks like I should ideally provide a new dedicated 12V+ power line from the lug of the disconnect switch to the breakaway switch. Then based on what you show I need to add a 40A thermal (auto reset) fuse on the 12V+ line coming in from the 7 pin. So my existing 30A auto reset fuse appears both undersized and wired improperly.
Since you don't have a power tongue jack, the 30 amp auto reset fuse could be used instead of the 40. The 40A would be better if you ever decide to add the powered tongue jack. Oh, the 40A is short protection for the wiring and allows the TV to supply power to the trailer / charge the trailer batteries

2. The frame grounds should not be used for the battery return paths. Only the trailer brake/stop/turn/running lights and brakes use the trailer frame as a negative return path.

Ok, understood.

The negative lug on the back of the WFCO is where your 6 awg negative wire should terminate.

Ok makes sense. Should I also upgrade the existing 10AWG wire from the WFCO DC board lug to the rear ground stud to 6AWG?
For as short a run of wire as the 10 ga, it should be Ok as there will not be enough voltage drop to worry about. But upgrading it to 6 ga wouldn't hurt either.

The negative lug on the back of the WFCO is also where all the trailer device negative wiring is terminated and it has one wire connected to the trailer frame.

Got it. Should the ground wire from the negative lug on back of the WFCO to the frame ideally be upgraded in size?
that ground wire is used when the emergency brakes activate or you are using the trailer batteries to light the tail lights with a jumper at the 7-pin so 10 ga is fine

The other frame ground is in your 7-pin junction box and is shown in the diagram.

Understood. I will leave this ground line alone.

3.The ground on the WFCO AC panel is tied to the trailer frame for safety reasons - the only time the frame ground should have current passing through it is when an electrical fault has occurred - it normally does not carry any current. The hot (black) and neutral (white) wiring are what is carrying the 120V current.

Understood. Thanks.

[tdf-texas]

Originally Posted by rubicon327

Tom: I noticed you moved the 12V+ power to the breakaway switch to the battery side of the disconnect switch. Is this to ensure that the breakaway switch power from onboard battery cannot be turned off under any circumstances? Like forgetting to turn battery isolation switch back on before towing if it was off for storage. Oliver does not have a battery disconnect switch that I know of but they do tie the breakaway switch power in separate from the 12V charge line like you show to avoid it being subject to a failed/tripped 40A breaker. (Pink line in attached schematic)

Yes, the emergency brake circuit should always be powered. There should never be a possibility of traveling with the trailer and the emergency brakes deactivated. The 40 amp breaker tripping shouldn't disconnect power to the circuit either and the reason for the dedicated wire to the emergency brake circuit.

When in storage, there would be no current going through the emergency brake circuit so no need to disconnect it using the battery cutoff switch.

It's funny you mention the Oliver wiring diagram. Ken Wetzl and I spent weeks discussing other trailer manufacturers wiring diagrams through emails to determine industry best practice for trailer wiring. Oliver was one of the wiring diagrams we studied and borrowed ideas from.

[Vermilye]

The -12V "ground stack", the bolt in the back of the WFCO power station will eventually get full as you add circuits. In both trailers I added a ground buss to make it easier to add connections.

[rubicon327]

Made good progress this morning after absorbing the changes that needed to be made (Thanks Tom!) and picking up a 40A auto reset circuit breaker and additional crimp fittings.

First photo shows 6AWG black and red directly to the lugs on the WFCO DC board. The smaller white and black on the left side are factory wires from upgraded Progressive Dynamics converter. The 6 AWG black leaves here and goes to the rear ground stud where it also meets a 6AWG direct from the battery and the rest of the equipment grounds as seen in the second photo. The 6AWG red leaving the WFCO is coming over from the BATT terminal on the new 40A circuit breaker which is landed with a short connection from the new rotary battery isolation switch (lug simply used as a node - connection not fused). The AUX terminal of the circuit breaker now accepts only the charge line from the 7 pin directly as seen in the third photo. The power for the breakaway switch was separated from the 7 pin charge line node and connected directly on the battery side of the isolation switch as seen in the fourth photo. Existing crimps by Escape are the yellow ones. Mine are the red and black with heat shrink. Power is back on. Now just double checking all connections and doing some tests. Any comments appreciated.

[Greg A]

Looking better, Dave. I'll leave the wiring comments to the pros, but those blue quick splice connectors in the 3rd pic I have been replacing everywhere I find them. Unfortunately, they are all over the trailer.
I've never liked those and quit using them when I built my fiberglass kit car in college.

[rubicon327]

FWIW the voltage as compared to WFCO DC lugs (from converter) dropped from 0.11V before wiring changes to 0.02V after the change. Might not seem like much but is a 5x reduction. When it comes to better battery charging I’ll take it.

[tdf-texas]

Wow! That was fast!

You will probably be a lot happier with the way it's wired now vs before. Great job!

[rubicon327]

Originally Posted by rubicon327

FWIW the voltage as compared to WFCO DC lugs (from converter) dropped from 0.11V before wiring changes to 0.02V after the change. Might not seem like much but is a 5x reduction. When it comes to better battery charging I’ll take it.

Meant to say voltage at DC lugs compared to across battery with converter on boost mode. Before changes voltage drop was 0.11V and after the changes it was 0.02V.

[rubicon327]

Originally Posted by tdf-texas

Wow! That was fast!

You will probably be a lot happier with the way it's wired now vs before. Great job!

Thanks Tom. Can’t thank you enough. I double and triple checked that I’m wired equivalent to your schematic. Tested the charge line from tow vehicle for voltage with truck hooked up and the breakaway system (with 7 pin disconnected) to ensure all wheels locked up with batt disconnect on or off. All is working well.

By the way this is the disconnect switch I used:
https://powerwerx.com/panelhdsw-heavy-duty-switch

Phase 2 will be replacing the metal junction box with one with color coded studs and replace the 7 pin umbilical while I’m at it.

https://www.etrailer.com/Accessories...er/e99009.html
https://www.etrailer.com/Wiring/Hopkins/H20046.html

[rubicon327]

Originally Posted by Vermilye

The -12V "ground stack", the bolt in the back of the WFCO power station will eventually get full as you add circuits. In both trailers I added a ground buss to make it easier to add connections.

Great idea. Thanks Jon.

[tdf-texas]

Originally Posted by rubicon327

Phase 2 will be replacing the metal junction box with one with color coded studs and replace the 7 pin umbilical while I’m at it.

https://www.etrailer.com/Accessories...er/e99009.html
https://www.etrailer.com/Wiring/Hopkins/H20046.html

Wow! That is one very expensive 7-pin connector. I ordered mine from Amazon and I am very pleased with the quality. The wire color coding matches our trailers.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[rubicon327]

Originally Posted by Greg A

I'll leave the wiring comments to the pros, but those blue quick splice connectors in the 3rd pic I have been replacing everywhere I find them. Unfortunately, they are all over the trailer.

Greg: What is the best replacement for these again?

[tdf-texas]

Originally Posted by rubicon327

Greg: What is the best replacement for these again?

https://www.youtube.com/watch?v=uhzXRIj5FaY