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'16 2500 159 HT Granite Window - OH(io)
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Does that switch at the fuse block or somewhere else? I am assuming that it is a 15 amp / 12 volt source?
There are relays and associated fuses in the PDC under the hood near the steering column. T2 and F14 for the front, and T17 and F9 for the rear. (You may not have the rear outlet depending on options)
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2019 Promaster 3500 Silver high top 159"
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The 12v aux power on the dash goes to a 20a fuse. Dunno how I know that. I use that to energize the relay for my mega head lamps and wake up signal for the radio.

I used a relay for the lamps but once I found out about the 20a, I could have wired them direct as they only draw about 7 amps.
 

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I also have a Renogy DC-DC that needs a D+ connection. I tapped the feed to the 12V cig-outlet in the dash. It meets D+ criteria and works just fine. Regardless of where you tap, it helps to put a switch in the D+ wire so you have manual control, too. FYI, D+ is just a relay trigger, so it hardly draws any amps.
 

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2017 PM2500, 159"WB
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Discussion Starter · #27 ·
I also have a Renogy DC-DC that needs a D+ connection. I tapped the feed to the 12V cig-outlet in the dash. It meets D+ criteria and works just fine. Regardless of where you tap, it helps to put a switch in the D+ wire so you have manual control, too. FYI, D+ is just a relay trigger, so it hardly draws any amps.
I ended up wiring to fuse 31 as Larry K suggested, very easy (now just gotta reinstall all the plastic covers), it shuts off when the car is off. I dont love the ability to draw 40 amps with the key in the On position but not with the engine running so for now I'll just have to not forget but a switch is a good idea. I think I'll try to find one with an LED light to make it easy to know if its running or not.

Now I'm trying to figure out why my 40 amp renogy DC-DC charger is only pulling 30-35 amps, but that may be a topic for a different thread.
 

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2014 136” HR
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2017 PM2500, 159"WB
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Discussion Starter · #31 ·
I have the Renogy DCC50 charge controller and I have never seen more than 40-45A going into the batteries with the engine running. Close enough for me.
Interesting, I've seen multiple videos where people show theyre pulling the exact advertised amperage if not slightly more on these Renogy units. What factors in the usage or installation do you think could lead to variation?
 

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Good question. Could be differences in battery monitors, SOC, or RPMs maybe. However, my shorepower charger is set at 80A and it can maintain that throughout bulk phase, independent of SOC. Output also doesn't appear to increase with engine RPM, but I haven't tracked it closely (yet). I suppose it could also be compensating for voltage drop, but that should be negligable with my 2/0 cabling. Dunno.
 

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2017 PM2500, 159"WB
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Discussion Starter · #34 ·
If you find out, let us know. I've been curious myself.
Not sure I have an answer but I measured 40 amps last night, I redid my starter battery connection to use a MEGA fuse in the open spot though I really doubt any change in that connection would affect the current. I was also running a couple things in the van for a while so maybe having a load on the battery bank makes a difference?
 

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Saw this on another forum. Makes sense to me:

"Max Rated Output Power:
20A model 250 watts ... 250W/20A = 12.5V
40A model 500 watts ... 500W/40A = 12.5V
60A model 750 watts ... 750W/60A = 12.5V

so at 14.4V I'd assume that means:

20A model 250 watts ... 250W/14.4V = 17.36A
40A model 500 watts ... 500W/14.4V = 34.72A
60A model 750 watts ... 750W/14.4V = 52.00A"
 

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Just looking for a d+ connection, I'm planning on putting my electrical in the back garage, I've read all the d+ threads and was wondering if anyone ever spliced into rear tail light daytime running lights circuit. I run these always on and since it's right there! Why not? Charger just needs a signal that van is on and this would provide the signal. As a benefit by cutting off DLR's it would stop the charging from alternator. Just thinking out loud here. Very 1st post, rather than starting a new thread thought I'd try here. Thanks!
 
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