Overkill Solar 4s BMS 120a LifePo4 Lug Size
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cargovanconversion
Building the ultimate Van Life home.
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Just installed two of those; used a 6AWG lug and a hydraulic crimper. Worked perfect!
See it here:
According to the Wire Combination Calculator (linked below), three 10 awg wires combined would be 5 awg. I don't recall clearly what size I used, but mine would be different since I have three 8 awg wires. I probably used 4 awg. According to the calculator, that would have been a tight fit.
Bob142
Build more, learn more.
As @cargovanconversion wrote, for the three standard 10 AWG wires it's definitively a 6 AWG lug.
No fancy video from me but here's photo evidence as well as a link to a post from Steve (Overkill Solar guy).
Finally found a LiFePO4 BMS with Low-temp Charging Protection
As far as I know, the Aliexpress store I linked to is from the manufacturer. Their website: https://heltec-bms.com/ And yes, low temp cut-off works fine and is configurable.
diysolarforum.com
Thanks for the calculator.
John, are you bored or looking for something specific? You've jumped into the Wayback Machine on a number of threads over the past week.
Well, in this instance, the calculator came in handy for knowing what size lugs to buy.
Just thought I'd thank you.
That calculator is indeed handy. I've posted it - and used it myself - quite a few times.
While I don't need an app for that one, I've been tempted to find a wire gauge calculator for my phone. It would be quite rare that I need to use it in the field for myself, but if I was troubleshooting something for another RV owner, it might come in handy to prove to them that their wiring was too small.
That calculator appears to show the effective gauge of the combined wires - i.e. how much juice can be pushed through. Not physical size and certainly nothing as far as what size lugs to use.
I've got the Overkills and I'm looking to attach three 8wg on each side. From what I can tell, the lug size to accomodate those wires into a single terminal is 4awg. Does this sound accurate to you guys? Thanks!
I've got the Overkills and I'm looking to attach three 8wg on each side. From what I can tell, the lug size to accomodate those wires into a single terminal is 4awg. Does this sound accurate to you guys? Thanks!
From my prior post, that sounds pretty close to what I used. I had to scrounge around town for a suitable lug.
The physical size of the combined strands is really what you are looking at, so it should fit in a lug that corresponds. Physical size and load carrying capacity are most assuredly related.
I can check, but two 8 awg wires should fit in a lug designed for 4 awg. Every manufacturer sizes things a bit differently.
The calculator tells me that two 6 gauge wires corresponds to 3 gauge. Depending on which brand of wire I use, a 2 gauge lug is working well.
The BNTECHGO 6 awg wire has finer strands, and seems physically larger, and two are a very tight fit in an Ancor 2 gauge lug.
Amazon.com: 6 Gauge Wire, SHONSIN 6 AWG Silicone Wire 100% Copper (20ft / 6.1m Black) Ultra Flexible High Temp 392℉/200℃ 6AWG Wire 2680 Strands 0.08mm (13.47mm2) Rating 100 Amp 600V : Electronics
Buy 6 Gauge Wire, SHONSIN 6 AWG Silicone Wire 100% Copper (20ft / 6.1m Black) Ultra Flexible High Temp 392℉/200℃ 6AWG Wire 2680 Strands 0.08mm (13.47mm2) Rating 100 Amp 600V: Power & Ground Cable - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
smile.amazon.com
The SHONSIN 6 gauge wire is smaller in diameter and fits easily in the same lug (for me). I have gone with the BNTECHGO since it is tinned.
So today I hit a local hardware store and picked up a couple of lugs, a 4 and a 2, and also got a bit of 6awg wire, thinking about putting a pair of that gauge wire down on two of the three spots on either side of the BMS, and then combining those two wires into a single lug - the pair of 6 awg wires fit reasonably well together into the 2 gauge lug.
But I'm also thinking I ought to do three runs of 8awg and maybe run those into a 4 gauge lug.
But I'm also thinking I ought to do three runs of 8awg and maybe run those into a 4 gauge lug.
On a slight tangent - the raised M6 threaded terminals you can get with these BMSs - are those bits of hardware something standard and available in general? I'm now thinking (from advice from a friend) I should try and get hold of some of these and solder them on. I was leaning toward just using some very short M6 bolts/nuts to attach a lug on those contacts, but friend suggests that board may not be up to that sort of physical stress, hence why the wires are either soldered or the raised terminals are soldered.
I haven't seen any for sale, but I haven't been looking.
Personally, that is what I order, the ones with the M6 threaded terminals. If they aren't available or your BMS doesn't have it, crimp a lug on and be done. No need to overthink it. The board is made out of fiberglass, how much stress were you planning on putting on the BMS? Why would there be any movement or stress on the board?
JBD will manufacture whatever version you want if you order enough of them. Sometimes 5 is a minimum order, sometimes 20.
There was a thread posted within the past 6 months where someone found a match to the threaded terminals that go on the circuit board of the BMS. I believe they still get soldered on. Otherwise, there are many of us that have wires soldered to the circuit board and I can't recall reading of any issues with that connection.
Nice, if you remember where it was, I'd look at it. But don't go out of your way.
Yes, I have both, those with soldered wires, and those with terminal screws. I prefer the terminal screws, but that is simply because you can make a neater more professional cabling job.
Amazon.com: IIVVERR 10 Pcs M6 6P PCB-5 Self-locking Snap in Screw Terminal w Round Spacer Screw (10 Unids M6 6P PCB-5 Cierre automático en el terminal del tornillo w Espaciador redondo Tornillo : Everything Else
Amazon.com: IIVVERR 10 Pcs M6 6P PCB-5 Self-locking Snap in Screw Terminal w Round Spacer Screw (10 Unids M6 6P PCB-5 Cierre automático en el terminal del tornillo w Espaciador redondo Tornillo : Everything Else
www.amazon.com
This is what I found - the sizes listed look good as far as the measurements I took on the unit. Dirt cheap too, shipping was more, and the big bummer is delivery isn't til the end of the month or early November.
I'll see how these work and report back once they arrive.
acdoctor
Solar Enthusiast
I desoldered the small wires and soldered # 2 awg to the boards working great.
acdoctor
Solar Enthusiast
I agree. If the screw terminals were available when I bought my BMS, I would have absolutely gone with those. I have three wires coming out each side of my BMS. It's an ugly wiring job.
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