DerpsyDoodler
Solar Addict
- Joined
- Jan 10, 2021
- Messages
- 2,247
So when your application calls for 4/0, you go with a mcm equiv of 2 sizes larger? I'd just assume go with what ampacity dictates and keep the parallel cables of equal length. Not that your approach won't work. It's all about resistance. Those 2 sizes larger just aren't necessary if you keep the parallel cables/bars similar lengths. Maybe an inch is fine, but when I'm cutting cable, I cut the first piece to length then use it as a jig. Unless you have really bad eye-sight, you'll get it within a 1/2" or less.If the current in the cables is high, near the max ampacity of the cable, then keeping them all pretty darned close in length is more important. But if the current is relatively low compared to what the cable can handle, it's not so important. If the voltage drop in unequal length cables has a couple zeroes after the decimal point, the batteries would charge and discharge so closely together that you'd never have any problems
I would try to stay pretty close with all cables when paralleling batteries . . . . but I wouldn't be measuring with a micrometer - An inch or two isn't that big a deal, IMO . . . . assuming adequately sized cables - Which for me is a wire gauge or two above what's minimally called for
Don