Alright, so the manual says 4 AWG (21.1mm^2) is supported. It even makes a note that a hex crimped ferrule is required for 16mm^2 (6 AWG) cable to fit.
It took a lot of searching, but I found a hex crimper capable of 4 AWG, but it doesn’t the crimped wire end does not fit. It measures roughly measures 6.4-6.5mm diameter, while the terminals on my Orion XS measures 6.33mm.
Bare 4 AWG is even larger - like 7.2mm diameter.
The manual says that a ferrule is not required for the wires in the list. It specifies that if using 6AWG with a ferrule, then the only way that would fit is with a bootlace ferrule with a hexagonal crimp.
That said, personally I’d consider 6AWG the maximum practical gauge to fit into the XS connectors. I can fit 4AWG in (so long as it’s correct high-strand cable, not multistrand), but it takes patience and extreme attention to detail to ensure that there aren’t any runaway strands poking out, as 4AWG is really and truly the absolute maximum gauge the connector could possibly hold.
So does that mean 4 AWG with a hexagonal crimped ferrule will fit or not?
I was able to cut and re-strip my 4 AWG leads and get them to fit. As you said, patience and attention to detail to ensure all strands made it in. A few leads I needed multiple attempts (ie cut, restrip, and reinsert).
But if I ever need to remove the Orion for service, this is going to be a pain. My Orion is not an easy location to mount and requires removing several other components first to remove it. If the terminals were bigger, I could more easily install leads in place without removing those components.
6 AWG is too borderline too small for my wire run distance (20’ positive, van chassis for negative)
That would be a no. 6AWG with a ferrule will fit only if it’s the right kind of ferrule crimped the right way. 4AWG will only fit bare, and even then barely.
Yeah a 40’ round-trip circuit, I’d go to 2AWG at a minimum, preferably 1AWG for that long of a run… and then just use PowerPosts or something similar to step the wire size to 6AWG just before the charger.
How critical is voltage drop on the output lead? Per blue sea, up to 50feet can be handled by 6 AWG with 10% voltage drop.
I have the input and shared ground leads under 1 foot - both to the battery. I also added another 4 AWG between the battery and the chassis ground - also roughly about a 1 foot.
Ground is handled by the van’s chassis. and the house batteries are connected via short 4 AWG cable as well.
That all said, my alternator is only 105A, so the Orion is set to a 25A input limit currently until I can figure out the max my alternator can handle.
Generally speaking, anything over 3% voltage drop is considered critical and shouldn’t be done with anything other than very low-current applications like LED lights or something, and even then best avoided.
I’d also personally suggest reconsidering your mounting location; A., the unit is best mounted closer to the target battery than the input battery if it’s necessary to justify one direction or the other, since the unit can compensate to some extent for voltage drop on the input but cannot compensate for voltage drop on the output; B., you will need to be accessing it over its lifespan, if for no other reason than to periodically re-check torque on the terminal connectors. This is done once or twice a year even on fixed installations, but on mobile installations it’s best to re-check torque on all your electrical connection fasteners every few months or so.
What gauge can I consider the ground through the chassis?
40’ of 4 AWG can handle up to 30A with a 3%/critical voltage drop. Only 22’ of those are feet are 4 AWG. The remaining distance could potentially be shorter, so the positive cable takes many twists and turns that the chassis does not.
The way my van is setup, my options were next to the starter battery, under the hood or on the frame rail, where the leisure/house batteries are located. On the frame rail, the Orion and it’s terminals would be subject to dirt/road grime, water/etc etc.
Checking torque is feasible enough without removing components. It’s just there’s poor access to reinserting 4 AWG wire when the terminal clearance is so painstakingly tight.
