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Discussion Starter · #21 ·
@van_dammit Would you be willing to post your finalized diagram (or as close to finalized as it can be at this stage)?
Absolutely! I fixed a few things people pointed out, I hope this helps out

  • added some approximate wiring distance to give a better idea of where things are at
  • fixed the Shunt connection in the diagram
  • removed the 250A breaker between the house battery and Blue Sea On/Off switch
  • decided to ground the Negative busbar to the van chassis with 2/0 awg instead of the 4 awg to the starter battery
  • changed my mind about the inverter, going with 2000W Renogy instead of the Gowise, just to stay on the same brand as much as possible. Plus the Renogy was on sale for the holiday.
  • going with a 700W microwave instead of 1000W just to be safe
  • updated the Diesel Heater wire to 12 awg instead of 14 awg
  • 12 awg for my LED Cabinet lights is overkill but I ran out of 14 awg and had just enough 12 awg to run it

Questions:
  • 4awg on going to a 90A breaker to my Blue Sea 100A Fuse block, is this okay to go smaller if I have to? Reason is that the 100A Bussman breaker may not arrive until mid December, I can get the 90A in a few days...
  • should my 80A breaker be closer to the starter battery? if so I might look at putting it by the driver's seat instead of in the back with everything else. I don't really like the idea of electronics near me just in case I spill a drink or something but hey, I guess I have a starter battery underneath my feet driving.
  • where can I find a 250A name brand breaker? Blue Sea and Bussman only go up to 200A. I have two of these now TTocas 250A breakers (return window exprired) Any thoughts here?

Font Rectangle Parallel Technology Screenshot
 

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Absolutely! I fixed a few things people pointed out, I hope this helps out

  • added some approximate wiring distance to give a better idea of where things are at
  • fixed the Shunt connection in the diagram
  • removed the 250A breaker between the house battery and Blue Sea On/Off switch
  • decided to ground the Negative busbar to the van chassis with 2/0 awg instead of the 4 awg to the starter battery
  • changed my mind about the inverter, going with 2000W Renogy instead of the Gowise, just to stay on the same brand as much as possible. Plus the Renogy was on sale for the holiday.
  • going with a 700W microwave instead of 1000W just to be safe
  • updated the Diesel Heater wire to 12 awg instead of 14 awg
  • 12 awg for my LED Cabinet lights is overkill but I ran out of 14 awg and had just enough 12 awg to run it

Questions:
  • 4awg on going to a 90A breaker to my Blue Sea 100A Fuse block, is this okay to go smaller if I have to? Reason is that the 100A Bussman breaker may not arrive until mid December, I can get the 90A in a few days...
  • should my 80A breaker be closer to the starter battery? if so I might look at putting it by the driver's seat instead of in the back with everything else. I don't really like the idea of electronics near me just in case I spill a drink or something but hey, I guess I have a starter battery underneath my feet driving.
  • where can I find a 250A name brand breaker? Blue Sea and Bussman only go up to 200A. I have two of these now TTocas 250A breakers (return window exprired) Any thoughts here?

View attachment 80009
Really appreciate this, thanks. We also have the 136" wb and expect similar loads so this is a great guide. A few differences in our plan:
  • Two 100aH SOK LiFePo batteries (currently out of stock)
  • Holding off on solar for the first year
  • No diesel heater or weBoost to start
  • CPAP is another 120v load
Do you mind if I modify your diagram and post it here for input? Despite hours of research, the electrical remains far beyond my comfort zone!
 

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Hi van dammit


Questions:
  • 4awg on going to a 90A breaker to my Blue Sea 100A Fuse block, is this okay to go smaller if I have to? Reason is that the 100A Bussman breaker may not arrive until mid December, I can get the 90A in a few days... I think you will be fine with the 90, but best to size the wire for the 100
 

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2014, 138WB, High Roof, Gas, SW MT
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Hi,
The way to size the breaker to your DC fuse panel is to add up all the DC loads that are likely to be on at the same time, then add a bit of margin, then add any loads you think you might want to add in the future. The wire and fuse coming to the DC panel only have to be good for this sum. The only function of this 90 amp breaker is to protect the wire from the house battery to the DC panel. By my quick mental add up of your loads, it seems like 90 should be fine.

The 80 amp breaker on the run from the van battery should be as close to the van battery as possible. Reason being that the wire between the van battery terminal to the 80 amp breaker is unprotected from a short to ground. A lot of people use a fuse mounted to the spare hole in the plate attached to the van battery plus terminal.

On the 250 amp breaker, the two you have in hand seem like they may be better than the run of the mill cheap Amazon breaker. They list several specs that it meets and mention ignition protection. This could all be BS, but it gives some hope they might be descent breakers. They say that the 250 amp breaker "No Manual button disconnect". The way I read that is that you won't be able to use it as a switch to turn off the inverter power. This seems unusual, but may not be a deal breaker for you.

Gary
 

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Your battery rated at 125A isn't up to the task of a 2000W inverter. Look at eBay I found Renogy 100Ah Lithium for $375/ea (asking$400) get two, then use a battery selector switch (not an off/on switch) to parallel them, will be ok for 200Amps. Take the DCC-50 to the starting battery ground. The van has poor grounding thru the body, most of the panels aren't welded, but joined with a goop.. It's very important to have 0 ohm reading and zero voltage drop. I know you have a fuse block, but I really prefer a DC Distribution Panel to easily secure power to devices. Your heater will be on all the time, lit up wasting power. With the DC panel, you can delete the pump switches. 14 AWG is an overkill for LED lights, one light you have 12AWG. Connection 22AWG to 12AWG is a pain. 14AWG, is fine for cig outlets. Motors and compressor are the devices that voltage drops hurt. but with a lithium battery you are running at a higher voltage than LFA batteries. So voltage drops aren't a problem. Most wiring problems, it's never the wiring size, it's always the connection points. Unless someone made a gross error.
 

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Hi,
The way to size the breaker to your DC fuse panel is to add up all the DC loads that are likely to be on at the same time, then add a bit of margin, then add any loads you think you might want to add in the future. The wire and fuse coming to the DC panel only have to be good for this sum. The only function of this 90 amp breaker is to protect the wire from the house battery to the DC panel. By my quick mental add up of your loads, it seems like 90 should be fine.

The 80 amp breaker on the run from the van battery should be as close to the van battery as possible. Reason being that the wire between the van battery terminal to the 80 amp breaker is unprotected from a short to ground. A lot of people use a fuse mounted to the spare hole in the plate attached to the van battery plus terminal.

On the 250 amp breaker, the two you have in hand seem like they may be better than the run of the mill cheap Amazon breaker. They list several specs that it meets and mention ignition protection. This could all be BS, but it gives some hope they might be descent breakers. They say that the 250 amp breaker "No Manual button disconnect". The way I read that is that you won't be able to use it as a switch to turn off the inverter power. This seems unusual, but may not be a deal breaker for you.

Gary
Gary, can you clarify: "A lot of people use a fuse mounted to the spare hole in the plate attached to the van battery plus terminal." Is this in addition to the 80amp breaker or instead of?

Thanks!
 

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2014, 138WB, High Roof, Gas, SW MT
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Gary, can you clarify: "A lot of people use a fuse mounted to the spare hole in the plate attached to the van battery plus terminal." Is this in addition to the 80amp breaker or instead of?

Thanks!
Instead of the 80 amp breaker.

Its the 100 amp MEGA fuse in this picture - not the most elegant hookup, but you get the idea...
This is looking down on the van battery.


Gary
 

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Isn’t the 14AWG to the fridge a little thin?
 

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I bet the in-rush current to the refer is much greater than 5a running. Still even if it were 10A that is only a 4% drop. 14 ga should be fine.

@GaryBIS I connected my B2B to the red regular fuse on the fuse block (the up-fitter fuse?). Was that a mistake? Should i have used a separate fuse like your photo shows? So far after a year of use no issues...
 

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I bet the in-rush current to the refer is much greater than 5a running. Still even if it were 10A that is only a 4% drop. 14 ga should be fine.

@GaryBIS I connected my B2B to the red regular fuse on the fuse block (the up-fitter fuse?). Was that a mistake? Should i have used a separate fuse like your photo shows? So far after a year of use no issues...
Hi,
It looks like the red fuse is 50 amps - so, as long as your wire to the B2B is good for 50 amps, it seems OK to me. If you have other loads on the up fitter connection, they would be adding to the B2B load, and the fuse may blow with the when the B2B is drawing less than 50 amps.

Gary
 

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Hi,
It looks like the red fuse is 50 amps - so, as long as your wire to the B2B is good for 50 amps, it seems OK to me. If you have other loads on the up fitter connection, they would be adding to the B2B load, and the fuse may blow with the when the B2B is drawing less than 50 amps.

Gary
I don't have any upfitter loads, and my fuse is 70a and the b2b can draw 50a, but in practice I have never seen more than 40.

Thanks!
 

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I don't have any upfitter loads, and my fuse is 70a and the b2b can draw 50a, but in practice I have never seen more than 40.

Thanks!
My 2018 had a 70amp fuse & I also charged my house batteries from that fuse (but direct - no B2B). It must be a "slow to blow" factory 70amp as I would see spikes above 70amps when turned on. Then the charge rate would quickly settle down to around 60amps or less depending upon SOC.


Motor vehicle Coil Red Electrical wiring Gas
 

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Discussion Starter · #37 · (Edited)
Your battery rated at 125A isn't up to the task of a 2000W inverter. Look at eBay I found Renogy 100Ah Lithium for $375/ea (asking$400) get two, then use a battery selector switch (not an off/on switch) to parallel them, will be ok for 200Amps. Take the DCC-50 to the starting battery ground. The van has poor grounding thru the body, most of the panels aren't welded, but joined with a goop.. It's very important to have 0 ohm reading and zero voltage drop. I know you have a fuse block, but I really prefer a DC Distribution Panel to easily secure power to devices. Your heater will be on all the time, lit up wasting power. With the DC panel, you can delete the pump switches. 14 AWG is an overkill for LED lights, one light you have 12AWG. Connection 22AWG to 12AWG is a pain. 14AWG, is fine for cig outlets. Motors and compressor are the devices that voltage drops hurt. but with a lithium battery you are running at a higher voltage than LFA batteries. So voltage drops aren't a problem. Most wiring problems, it's never the wiring size, it's always the connection points. Unless someone made a gross error.
Now I have heard both sides to the Grounding debate. I got some advice to not ground to the starter battery due to the wire length of the 4awg cable. I've carved out a chassis grounding spot near the negative busbar and planning to use 2/0awg cable to connect it to the van, that sounded like it made more sense. But I do see all that "goop" between metal panels on the 2021.

I'm leaning to having the shorter cable setup even though the Renogy manual says to ground to the starter battery. I suppose I can change it up later if I start having bad results but others have said they get a better connection through the 2/0awg cable

I dont plan on having anything running in the van that is more than 1500W, i think the most would be a 120v water heating element which is 1300W draw. I've seen someone that has the same setup, 170AH with 2000W inverter. Also Renogy recommends that one 170AH is the minimum battery quantity for a 2000W inverter ::shrug
 

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Discussion Starter · #38 ·
Hi van dammit


Questions:
  • 4awg on going to a 90A breaker to my Blue Sea 100A Fuse block, is this okay to go smaller if I have to? Reason is that the 100A Bussman breaker may not arrive until mid December, I can get the 90A in a few days... I think you will be fine with the 90, but best to size the wire for the 100
I actually found a 100A Blue Sea breaker, so I think I should be all good here

Really appreciate this, thanks. We also have the 136" wb and expect similar loads so this is a great guide. A few differences in our plan:
  • Two 100aH SOK LiFePo batteries (currently out of stock)
  • Holding off on solar for the first year
  • No diesel heater or weBoost to start
  • CPAP is another 120v load
Do you mind if I modify your diagram and post it here for input? Despite hours of research, the electrical remains far beyond my comfort zone!
Sure thing Kathyks, I actually grabbed this diagram from someone else on this board and then Photoshopped my own stuff! I think that visuals, real pictures, help a lot for me
 

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Discussion Starter · #39 ·
Instead of the 80 amp breaker.

Its the 100 amp MEGA fuse in this picture - not the most elegant hookup, but you get the idea...
This is looking down on the van battery.


Gary
Gary, I may return this 80A breaker in lieu of this method. Just one question as to why you chose a 100A fuse on the battery? Isn't the default stock alternator in the PM at 70A? I thought 80A would be enough, no?
 

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Discussion Starter · #40 ·
Quick reminder that given the max discharge of the battery that 250A fuse will never pop. The BMS will shut the battery down first.

250A Breaker - 353250 OptiFuse | Circuit Protection | DigiKey Marketplace
I'm guessing that the other 250A breaker before the 2000W inverter is also probably useless. I didn't realize there was the 125A max output on the batteries, I missed that detail.

I suppose if I ever add another 170AH battery, they would come in play...
 
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