PD4045 12V neg please help!

[achill]

I’m restoring an ‘83 13’ and have removed all existing electrical and replaced with new wiring, fixtures, and outlets. I installed a PD4045KV power center, and have all the AC side wired, the converter hot connected to a breaker, and the ground bus grounded to the chassis. No problem there at all.

However, I am stuck on the DC side. I have all of the positives in their respective circuits, and the negatives connected to a separate bus bar I installed on the floor behind the unit. However, I have no idea where to connect this bus bar. Do I connect the battery’s negative cable to the bus bar and then the bus bar to the battery negative terminal on the PD4045? I need someone to explain what to do in the simplest terms possible lol. Pics of the front of the unit and the rear of the unit+bus bar included, and I have no idea why the site rotated my pictures, but I promise I did not install the unit upside down!

[redbarron55]

The negative side of the charger connects to the buss bar and to the frame ground. Each load will have to have both a negative (ground) lead and the positive from the circuit bed from the DC distribution panel. I connected my lines from the DC buss to a pair of barrier terminal strips for interconnection to those loads.



The buss bar is fastened to the new steel wheel wells I installed. The Barrier terminal strips are in front mounted on the wood floor. The charger/distribution is installed front of these in the sidewall of the twin bed.
You can bring the battery negative to the buss bar or the negative side of the charger as they should be connected together.

[achill]

Originally Posted by redbarron55

The negative side of the charger connects to the buss bar and to the frame ground. Each load will have to have both a negative (ground) lead and the positive from the circuit bed from the DC distribution panel. I connected my lines from the DC buss to a pair of barrier terminal strips for interconnection to those loads.



The buss bar is fastened to the new steel wheel wells I installed. The Barrier terminal strips are in front mounted on the wood floor. The charger/distribution is installed front of these in the sidewall of the twin bed.
You can bring the battery negative to the buss bar or the negative side of the charger as they should be connected together.

Thank you! We don’t have nearly as many DC circuits as you do, so I think this is what we’re going to do:
-positive circuits to the leads on the unit
-positive from battery to positive battery (DC) supply on unit
-Negative circuits to the bus bar
-battery negative to the bus bar
-bus bar to the negative battery (DC) supply on the unit
-insulated ground from the bus bar to the common grounding point on the frame.

Does this sound reasonable?

[redbarron55]

That sounds reasonable. In my case I have one end of the buss bar tied to the battery negative and the charger negative and the other goes to the frame.
Since I took that picture I added a ground current shunt in the ground lead from the battery to measure the current and DC power.
The basic setup is still the same.
I have voltage, current and power measurement for both the AC and DC systems as well as the system for the solar system.
Also I did re-route the power from the battery charger / battery to the solar charge controller and from there back to the PD buss.

[achill]

Thank you!! Fingers crossed the DC side as we’re configuring it works out!

[achill]

Originally Posted by redbarron55

That sounds reasonable. In my case I have one end of the buss bar tied to the battery negative and the charger negative and the other goes to the frame.

Quick question: does the converter charge the battery better if you have the battery and the converter both tied to the same nut on the buss bar? And then the other large nut on the other end of the buss bar tied to the chassis grounding point?

Also, I mounted the buss bar to the wood floor, is that fine?

[ROBERT ONEILL]

Never ever connect a 12volt ground to the same ground location lug on the frame as a 120volt ground. If 120 ground gets bad corrosion or loose you can feed through the 12 volt and fry many items. Also you could end some ones life early. Make a separate ground lug for both and check the tightness after a short time to ensure it is still tight. New cable end lugs compress when you tighten them.

To be safe play it safe.

Hope your project turns of better than you expect it to .

[achill]

Originally Posted by ROBERT ONEILL

Never ever connect a 12volt ground to the same ground location lug on the frame as a 120volt ground. If 120 ground gets bad corrosion or loose you can feed through the 12 volt and fry many items. Also you could end some ones life early. Make a separate ground lug for both and check the tightness after a short time to ensure it is still tight. New cable end lugs compress when you tighten them.

To be safe play it safe.

Hope your project turns of better than you expect it to .

Scamp uses a common grounding point on the frame for the 120V and 12V systems. The 120V ground should have no electricity flowing through it. You can test this with a volt meter on all of your outlet grounds. The true ground for the 120V system is the power source where your camper is plugged in, ie the campground. The progressive dynamics power center we installed has reverse polarity protection, so we’re good there. Where you could run into problems is when on generator power, as pretty much nobody connects those to an earth ground. That’s why you install GFI outlets everywhere or use combination GFI breakers.

[Alohah3]

where are you installing the PD4045 on the 13ft scamp? I have one to install in a 1984 13' standard layout. thank you, Brad

[achill]

Originally Posted by Alohah3

where are you installing the PD4045 on the 13ft scamp? I have one to install in a 1984 13' standard layout. thank you, Brad

Hi Brad, the previous owner of our 1983 cut the middle out of the front couch to make a dinette, so we installed in the street-side seat. Works really well there!