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DC-DC Chargers in Parallel

yeahnah

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Hi All, I have two Victron Orion Smart 12|12 – 30A DC-DC chargers on the way and I'm trying to figure out how to wire them in parallel.
Do I essentially just wire them as two stand alone DC-DC chargers running next to each other and have them separately fused?
Is there another way to do it? I've searched all over online and I haven't found an example of exactly how to wire them, just that they can be wired in parallel.
Thank you!
 
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Basically yes, Use breakers not fuses and keep them as near to battery to be charged as possible to avoid voltage loss. They run kind of hot so watch what you mount them on and next to.
 
Basically yes, Use breakers not fuses and keep them as near to battery to be charged as possible to avoid voltage loss. They run kind of hot so watch what you mount them on and next to.
Is there a reason breakers are preferred over fuses for this? I was originally thinking something like just adding two wires (one for each DC-DC) to the starter battery, each with their own in-line fuse.

I'll check if I can mount small busbars somewhere near the starter battery so there aren't too many wires coming off the starter battery terminal. Something like these:

71inFrjhHFL._AC_SL1500_.jpg
 
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So you are going to have 30a x2 and 400w of solar charging a 200ah 12v LiFePO4 battery? Thats a bunch.

I have 326ah of LFP and run 120a charge from a multiplus, I have 2x 50amp DC2DC chargers in parallel for a 100a total charge.. and will be going solar and trying to squeeze 400+w on the boat flybridge. The 100a DC2DC charge is only 1/3 of what the battery can handle, and I chose this way as we barely run the boat for longer than an hour or 2 on most trips.. so wanted to get the batteries charged as quick as possible.. I understand if in an RV thats touring you can get away with much less.

Steve
 
Is there a reason breakers are preferred over fuses for this? I was originally thinking something like just adding two wires (one for each DC-DC) to the starter battery, each with their own in-line fuse.

I'll check if I can mount small busbars somewhere near the starter battery so there aren't too many wires coming off the starter battery terminal. Something like these:

View attachment 53026
Those buss bars would be fine. I just like breakers for something like this as you can use the breaker to take one or both out of service as needed. I don't like pulling 40 Amp fuses on a "hot" circuit.
 
Nothing wrong with fuses, fuse the Orion at 50A each, they can pull up to 40 amps. If you use breakers only Bussman/Blue Sea are worth getting, eBay / Amazon unbranded are useless.
If using buss bars consider stud with ring terminations on the cables. I suggest you take the Orion outputs individually to the battery, fused at the battery, 50A.
The output is nominally 30A but may be higher initially.
As said the units run hot, if not cooled , the output current drops to protect the unit.
There is no low temperature disable on the Orion and no bus interface. Two control pins are available on the unit for external enable/disable.

Mike
 
I would recommend that it is good practice to have each of the DC-DC Chargers connect to the battery or battery bus. In order to avoid any interaction (called aliasing from the switching electronics) you do not connect the charger outputs together and then have a common cable run to the batteries.
 
I like breakers too. One reason is that since I want to arrive home with my batteries less than full I don't want to charge on the way home. The breaker makes it easy to switch off the charging. Make sure to use a quality breaker though.
 
Those buss bars would be fine. I just like breakers for something like this as you can use the breaker to take one or both out of service as needed. I don't like pulling 40 Amp fuses on a "hot" circuit.
Great point on the breakers!
 
Nothing wrong with fuses, fuse the Orion at 50A each, they can pull up to 40 amps. If you use breakers only Bussman/Blue Sea are worth getting, eBay / Amazon unbranded are useless.
If using buss bars consider stud with ring terminations on the cables. I suggest you take the Orion outputs individually to the battery, fused at the battery, 50A.
The output is nominally 30A but may be higher initially.
As said the units run hot, if not cooled , the output current drops to protect the unit.
There is no low temperature disable on the Orion and no bus interface. Two control pins are available on the unit for external enable/disable.

Mike
I read they need 10cm above & below for effective cooling. Maybe I'll also mount a computer fan above them that runs when they're activated.
About those control pins, I read the units have a voltage sensor, but I was thinking of using a manual switch with those control pins near the dash board for greater control if needed (e.g. I'm idling for a while or something).
 
I would recommend that it is good practice to have each of the DC-DC Chargers connect to the battery or battery bus. In order to avoid any interaction (called aliasing from the switching electronics) you do not connect the charger outputs together and then have a common cable run to the batteries.
you mean instead of using a common wire that branches off into two?
 
I like breakers too. One reason is that since I want to arrive home with my batteries less than full I don't want to charge on the way home. The breaker makes it easy to switch off the charging. Make sure to use a quality breaker though.
I was thinking of using the control wires for these things, but I like the breaker idea too. Just need to find mounting near the starter battery....
 
I was thinking of using the control wires for these things, but I like the breaker idea too. Just need to find mounting near the starter battery....
I put my input breaker on the base of the driver's seat, Makes it easy to reach down and shut it off and turn it on. However, my battery is under the seat so it made that easy.
 
I put my input breaker on the base of the driver's seat, Makes it easy to reach down and shut it off and turn it on. However, my battery is under the seat so it made that easy.
In hindsight that now seems very obvious! Not sure why I didn't think of that... Thanks!
 
My Lynx Distributor has no room for the 2nd Orion DC-DC and I'm trying to avoid getting a 2nd Lynx Distributor. Can I wire the Orion DC-DC units in Parallel from the Starter to the Orions, then feed their outputs onto small busbars (one + and one -) that then feed as one cable into the Lynx Distributor so they share a 100 Amp mega fuse inside the Lynx Distributor? I'd beef up that shared wire that feeds from the busbar into the Lynx Distributor.
 
My Lynx Distributor has no room for the 2nd Orion DC-DC and I'm trying to avoid getting a 2nd Lynx Distributor. Can I wire the Orion DC-DC units in Parallel from the Starter to the Orions, then feed their outputs onto small busbars (one + and one -) that then feed as one cable into the Lynx Distributor so they share a 100 Amp mega fuse inside the Lynx Distributor? I'd beef up that shared wire that feeds from the busbar into the Lynx Distributor.
Hey there, we are interested in doing the same. Did you do this and if so did it work out?
 
Hey there, we are interested in doing the same. Did you do this and if so did it work out?
Hi, I haven't installed this yet (the build is slow with kids and a business) but I have all the parts in my garage and I have decided to go this route of wiring the two Orion DC-DC outputs into a busbar (one for + and one for -) then feeding from the busbars into the Lynx Distributor. I've found a lot of good high amperage covered busbars on Amazon. It works out much cheaper than two Lynx Distributors and it also saves space as those Lynx Distributors are quite large. Here are the busbars I purchased - I got the 5/16" bolt version as I believe the Lynx is M8 which is basically 5/16" so I can use the same lugs:

 
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Hi, I haven't installed this yet (the build is slow with kids and a business) but I have all the parts in my garage and I have decided to go this route of wiring the two Orion DC-DC outputs into a busbar (one for + and one for -) then feeding from the busbars into the Lynx Distributor. I've found a lot of good high amperage covered busbars on Amazon. It works out much cheaper than two Lynx Distributors and it also saves space as those Lynx Distributors are quite large.
Yes, I agree the lynx is huge. So, I have seen on a shematic from Victron where you only run the postive wires to the busbar and the negatives are only linked together from start battery. Can I ask are you running one pos and one negative from the starter battery and them linking them together and also what size wiring are you using?
 
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