1994 International 4700 Conversion Begins

Lol, getting the instructions out to wire up the CB radio. What do ya know, there are actual instructions for connecting to a negative or positively grounded system. It's also marked on the power wire for the radio. That's helpful information!

Scooter...

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Ozrockrat

Expedition Leader
I think you may have a terminology problem. It is not really a positive ground system. It is just the the ground of the controller is not tied to the negative but instead floats at a voltage above 0. Hence the reading you got of 7v.

If you really need something to put you to sleep sometime search up articles on ground loop fault detection.
 
I think you may have a terminology problem. It is not really a positive ground system. It is just the the ground of the controller is not tied to the negative but instead floats at a voltage above 0. Hence the reading you got of 7v.

If you really need something to put you to sleep sometime search up articles on ground loop fault detection.
Haha! I thought the same thing and called him, hoping to catch him before he hooked his radio up to reverse polarity. He did it right, though, and all is good there.
 
I think you may have a terminology problem. It is not really a positive ground system. It is just the the ground of the controller is not tied to the negative but instead floats at a voltage above 0. Hence the reading you got of 7v.

If you really need something to put you to sleep sometime search up articles on ground loop fault detection.
Haha! I thought the same thing and called him, hoping to catch him before he hooked his radio up to reverse polarity. He did it right, though, and all is good there.
Yup, all good. I certainly see why people get confused. The terminology causes the problem. It's pretty clear in my head now.

Thanks again guys!

Scooter...

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dwh

Tail-End Charlie
Ok, thank you.

I'm still trying to wrap my head around the concept but I think I get why they wire panels this way.
They wire (some) panels that way due to how the panels are made. If they put the contacts on the backside of the solar cells, they get a bit more power because the cells are not partially blocked by current carrying metal strips on the front of the cells.

But, for some reason, putting the contacts on the back creates a situation where if they wire the panel negative-ground and the aluminum frame is grounded to the planet (which it will be if installed on a building) a small surface charge builds up between the cells and the aluminum frame, which causes the cells to become slightly polarized. This reduces the number of photons entering the cell to produce electricity and reduces electrical efficiency slightly.

Apparently by wiring the panel in a positive-ground configuration, it causes that surface charge to dissipate, alleviating the problem.


If wired straight from the panel, controller to the battery it's a single path of electrical flow between the negative and positive. With the solar is part of that circle it adds power to the circuit to which the battery absorbs the power as needed.
It's a single circle, operating at a single voltage, with a PWM controller, which is just a high speed switch.

But with an MPPT controller, there are two circles, one on the solar side and one on the battery side, operating at different voltages.


Now, connecting the negative to chassis ground as I did changes that path and begins to try and charge the entire truck? This is what confuses the controller as the chassis becomes charged to Output Voltage from the solar panels it sees the batteries as fully charged.

Is this remotely close to what's happening? If not I'll delete the post as not to confuse anyone else!
That's the right idea. As I said - you create a bypass around the controller to the battery/chassis.


Adding panels is not the same as adding a new light or device to the truck, it"s an in-line charger…
The alternator is also an inline charger that does the same job. But you didn't wire the alternator in a way that bypassed the voltage regulator...like you did with the solar. :)
 
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Ok, thank you.

I'm still trying to wrap my head around the concept but I think I get why they wire panels this way.
They wire (some) panels that way due to how the panels are made. If they put the contacts on the backside of the solar cells, they get a bit more power because the cells are not partially blocked by current carrying metal strips on the front of the cells.

But, for some reason, putting the contacts on the back creates a situation where if they wire the panel negative-ground and the aluminum frame is grounded to the planet (which it will be if installed on a building) a small surface charge builds up between the cells and the aluminum frame, which causes the cells to become slightly polarized. This reduces the number of photons entering the cell to produce electricity and reduces electrical efficiency slightly.

Apparently by wiring the panel in a positive-ground configuration, it causes that surface charge to dissipate, alleviating the problem.


If wired straight from the panel, controller to the battery it's a single path of electrical flow between the negative and positive. With the solar is part of that circle it adds power to the circuit to which the battery absorbs the power as needed.
It's a single circle with a PWM controller, which is just a high speed switch.

But with an MPPT controller, there are two circles, one on the solar side and one on the battery side.


Now, connecting the negative to chassis ground as I did changes that path and begins to try and charge the entire truck? This is what confuses the controller as the chassis becomes charged to Output Voltage from the solar panels it sees the batteries as fully charged.

Is this remotely close to what's happening? If not I'll delete the post as not to confuse anyone else!
That's the right idea. As I said - you create a bypass around the controller to the battery.


Adding panels is not the same as adding a new light or device to the truck, it"s an in-line charger…
The alternator is also an inline charger that does the same job. But you didn't wire the alternator in a way that bypassed the voltage regulator...like you did with the solar. :)
Lol...yeah. I was thinking about the way the alternator is wired. Thanks for taking the time to explain it. I've Googled plenty and the detailed explanation is significantly better than anything I could find.

Thanks for the information. I know it's helped me and I know it will help those who come across these postings.

Scooter...

Sent from my LGMP260 using Tapatalk
 
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The solar has made it to a "floating" state. All is well now, thanks again.

I managed to get the PA speaker from the CB set up and tested in the back of the box while the batteries were charging. It will be useful to communicate with the kid along the road. Even with 35 feet of speaker extension wire the speaker is incredibly clear. I was expecting a bit more noise but it sounds very good. The radio plays a part in it as well but I'm happy.

To get it in that spot I had to de-solder the speaker wire and run the wire across the roof and down between the sheet metal from the external cabinet and interior plywood. There was not enough room for the extension plug.

Scooter...


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I'm looking at back up camera's, what do you folks think about wireless systems?

Scooter...
when you look at wireless check any info you can on "delay". As in if you have a half second delay on placement of image on screen...... you need to know that if say your backing up to a trailer hitch for you may have smacked the trailer tongue while your dash screen still shows your 3" away. Not sure if this issue is little less a problem or way more of a problem compared to wired setups or not.
 
I'm looking at back up camera's, what do you folks think about wireless systems?

Scooter...
when you look at wireless check any info you can on "delay". As in if you have a half second delay on placement of image on screen...... you need to know that if say your backing up to a trailer hitch for you may have smacked the trailer tongue while your dash screen still shows your 3" away. Not sure if this issue is little less a problem or way more of a problem compared to wired setups or not.
Ah, good to know! I had not thought of the possibility of a delay.

I'm considering wireless simply because I'm getting tired of running wires!

Scooter...

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If you haven't picked out a system yet, here is a good place to start.

https://www.rearviewsafety.com/safety-solutions/backup-camera-systems.html

This is probably who I will buy from when the time comes. Bob Renz (Fambulance) is also looking a them for his source.
I see they are available on Amazon as well. Excellent!

Thanks!

Scooter...

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Looking at the vast amount of options available, I ended up going with a Coolwoo backup kit. All the systems seemed to have pro's and con's. The wife was not thrilled at any of them due to the amount of money I've been spending.

Ultimately, it came down to #1 the flush mount option, #2 the 4 pin connector, #3 size of the camera body and #4 the price. I only found a couple with flush mount kits, although I am sure there are more. We don't want anything up on the window or top of the dash.

There is a spot on the dash which faces the driver and just enough metal to mount a 7 inch monitor with some tweaking. I only have to remove the PTO switch and I've got a nice place to mount the screen and run the cable through. I am going to remove the PTO generator when I swap transmissions anyway. With the flush mount kit I think (I can and better, actually!) keep the screen out of my wifes knees when she's swiveling to go into the back.

Scooter...

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Lol, going through the other postings and seeing what people are doing is dangerous.

I think I "need" a bigger truck!

Scooter.

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The previously mentioned tweaking. To my surprise, there are a couple of compound angles I had to deal with.

Scooter...

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