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Distance from batteries to inverter charger

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My 2000 watt inverter charger manual says 5 feet from battery bank one way. I am about 8 feet away because I want to make the cut off switch easy to access. Round trip would be 16 feet compared to 10 feet. I am running 2/0 copper. Will that be a problem? Up date: I got it down to 13.5 feet with a few changes, 6.75 one way. Called the inverter reps and they say it should be o.k.
 
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Does the manual recommend a wire size for that 5 (10) feet?

2000W / 12V = 167A. Round up to about 200A to be safe. For 200A at 8 feet (16 feet round trip) you should use 2/0 which is what you are using. 2/0 is good for the amps and good for voltage drop so I don't see a problem with the inverter being 8 feet instead of 5 feet given the wire size you've chosen. Can't hurt to confirm with the inverter manufacturer.

Make sure the cutoff switch can handle 250A or more. 300A would be better, especially if you have a 250A fuse to the inverter. You don't want a switch supporting less than the fuse.
 
Thank you for your reply... The manual suggests 2/0 with a 250 amp fuse. I am using Blue sea #6006 battery switches, which are rated 300 amp continuous. I got it down to 13.5 feet.
 
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Just make sure you use really high quality marine-grade wire (pure copper, optionally tinned, very high strand count, 105ºC rated). Be careful with wire on Amazon. DO NOT end up with aluminum clad wire.
 
Ripple is a big player when the wire is not size per the manual. The calculations for inverters is not a straight Ohm's law calc and really needs to include inverter efficiency and ripple..

Undersized wire can prematurely damage the inverter and cause performance loss. I know we have an ABYC document that covers this topic in depth, but it is not shareable public information. That said, I know Victron has written a paper on this and dealers have been trained on this. Found one of the dealer training documents which allowed me to find it on-line. This is a very short doc, not the full info, but it sums it up.

Victron Ripple

171852118.jpg

https://www.google.com/url?sa=t&rct...y_system.pdf&usg=AOvVaw1RDPnWc1OiuEUwoHUrOzqb
 
Ripple is a big player when the wire is not size per the manual. The calculations for inverters is not a straight Ohm's law calc and really needs to include inverter efficiency and ripple..

Undersized wire can prematurely damage the inverter and cause performance loss. I know we have an ABYC document that covers this topic in depth, but it is not shareable public information. That said, I know Victron has written a paper on this and dealers have been trained on this. Found one of the dealer training documents which allowed me to find it on-line. This is a very short doc, not the full info, but it sums it up.

Victron Ripple

171852118.jpg

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwi32NbOhpryAhXSKVkFHS4JDggQFnoECAIQAw&url=https://www.victronenergy.com/live/_media/ve.bus:4._ripple_in_a_ac_battery_system.pdf&usg=AOvVaw1RDPnWc1OiuEUwoHUrOzqb
Thank you so much. Does it make sense to run a portion of 4/0 in the circuit, say from the battery bank to the main shut off switch to the positive buss bar. Of all the research I have done and , you tubers, you are the first to mention inefficiency of unit and the ripple effect together in designing systems.
 
Does the manual recommend a wire size for that 5 (10) feet?

2000W / 12V = 167A. Round up to about 200A to be safe. For 200A at 8 feet (16 feet round trip) you should use 2/0 which is what you are using. 2/0 is good for the amps and good for voltage drop so I don't see a problem with the inverter being 8 feet instead of 5 feet given the wire size you've chosen. Can't hurt to confirm with the inverter manufacturer.

Make sure the cutoff switch can handle 250A or more. 300A would be better, especially if you have a 250A fuse to the inverter. You don't want a switch supporting less than the fuse.
Thank you, yes the manual said 2/0. I do have a possible problem . I have 2 100 ah batteries in parallel. I put a Blue Sea 250 amp fuse on each positive post. Now I have 3 250 amp fuses counting the inverter fuse. What do you think? Thanks...
 
IMO the limiting element will be the smallest gauge so run all 2/0 or 4/0 depending on how deep your pockets are.
 
2/0 wire is safe with 250A fuses. While the inverter needs 2/0, the battery cables might need 3/0 or 4/0 because the batteries need to handle the inverter current, the SCC current, and DC loads current. If it's all maxed out at the same time, the battery cables (between the batteries and to the bus bars) need to handle the full total.
 
My 2000 watt inverter charger manual says 5 feet from battery bank one way. I am about 8 feet away because I want to make the cut off switch easy to access. Round trip would be 16 feet compared to 10 feet. I am running 2/0 copper. Will that be a problem? Thanks
Typically no issue. Especially with the higher voltage of LFP.

Although honestly I would skip the switch and just remove the fuse for service. While the switch seems convenient... you may not use it for several years at a time. I certainly have not needed it. Just adds several more connections to develop resistance.
 
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