Has anyone considered rewiring a GEM to use external DC to DC converter and Charger?
Sure, it could be done.
What has changed since the last you dropped by?
Yes I am certain it can be done. Just wondering if anyone has tried or considering trying.
An easy swap.
For the adventurous, I have replacement DC-DC dci boards.
This Delta Q charger is not worth trying to restore as it was subjected to a high current condition. My issue is that I dislike the fact they placed the DC to DC converter in the charger, poor design in my opinion. I would like to add my own 6 bank charger and a DC to DC converter to run a 2013. But I am not sure how the PSDM would factor in a configuration of this type. Any ideas are greatly appreciated.
Wow- Ambitious. That is a little different from what you originally asked.
The problem I see right off is that you would be bypassing the PSDM to do the 6 bank charger. Doing this will mess up on how the SOC meter works (the battery display on your dash).
SOC meter not really a concern of mine. I would simply wire an LED SOC meter permanently affixed in dash.
How far along are you with this project?
Have not started as of yet. But looking to tackle this soon.
Have you already (recently) bought the batteries?
Is there any reason why you are choosing to stick with LeadAcid? You seem to be going through quite an effort for average performance and range.
What car is this going into?
Maybe we should review your goals?
Think you posted to wrong thread. This has nothing to do with the batteries and not using lead acid.
A few lines up you were installing a 6 bank charger. That was my assumption.
What are you running then?
AGM at the moment. Will later look at converting everything to lithium. But regardless of what batteries I use will not change rewiring of unit, only will change battery charger requirement.
I try to get a full grasp of what someone is trying to do and sometimes can adjust course a bit with a little nudge to avoid duplicating work.
Other than the little Shunt for the SOC meter, I don’t think the PSDM cares where it gets it’s power from. See if you can find a DC converter with dual outputs (one for constant 12v, one for switched) or use two converters.
The interlock from the charger can be bypassed so that isn’t an issue. You might have already done that.
(B+) from the interlock goes through the key and back through the PSDM to trigger the switched Key ON accessories output.
Thats what I am thinking as long it gets 12 volt input I can use terminal boards to redistribute as needed. I have not bypassed interlock at this point as I have been in a holding pattern for a couple months on this project since the Delta Q crapped the bed. Not sure how to bypass the interlock as of yet but definitely interested in that.
Normally, if your car is NOT plugged in but your charger is still wired up, it gets takes a a B+ feed (+72v) from the RED wire and passes it out to the Green wire output (essentially, [at rest] - the red wire and green wire are connected). (Don’t yell at me about the use of color codes here.
The green wire from the charger gets plugged into a Dark Green wire on the car.
When plugged in to 120v the red and green wires on the charger go open. The car sees this condition as a charge status and throws a light on the dash and the car will not move.
A common question is when people remove their charger they ask why their car thinks it is charging?
Another common mistake when hooking these up is they take the green wire and hook it up to Chassis Gnd, (or worse) hook it up to (B-) Poof! (you see the issue here?).
Bypass- (for late generation cars only) (in case someone else is dropping in on this topic)
The simple solution is to run a jumper wire from B+ (from the stud on your PSDM) and hook it to your Dark Green wire found in the car harness. I see that wire going to J1 pin J on your PSDM (if you lost track of it and need to ferret it out).
Now you have to warn people not to drive away with your car plugged in.
An external dc-dc is pretty much wire to wire.
Connect the dci output wires to the new converter and wire the input parallel the charger input wires.
Could you not just connect a 72V to 12V converter to the PSDM?
Wait, I think I misunderstood the q…
That is what Inwo was suggesting. The wires that formerly went to the internal converter part of the charger would go to the new External DC Converter.
Correct, 4 wires come out plus a duplicate ground 12v-.
12v always on
And control wire to turn switched 12v on.
The new dc-dc will have the same wires.