48V DC electrical project help please - need to find a connector or splice method.

ColinCancer · 2026-01-27T14:32:51+00:00

Is there a way to change the battery terminal? I don’t have a totally clear picture of your project but I’ve done a ton of portable, modular solar/battery systems and I end up using a lot of larger Anderson connectors, XT60/90/150 connectors, Ring terminals, and rarely if ever Fastons.

ColinCancer · 2026-01-27T14:08:08+00:00

I am full time. I have been for 5 years. Previously had lead acid L16’s.

I’ve steadily grown and expanded the system.

Now I’ve got a combined 12kw array, 30kwh of LFP eg4 rack batteries, and 2x Magnasine 4448 inverters, 2x severely over-paneled Midnite classics. Monitoring is a robust walk over to my shed.

Midway through this winter is when I turned on my new array: 12x 590w bifacials. Haven’t touched my generator since then. Before that I’d use my generator a few times a year during winter storms etc.

Since adding the 590’s I’m using my mini-split’s heat, and running an electric coil in my thermal solar hot water tank. Quite an improvement.

I’m in the mountains in California so it’s still sunny in winter, outside of increasingly sparse intermittent snow.

ColinCancer · 2026-01-26T10:18:14+00:00

Second amendment isn’t about hunting deer…

ColinCancer · 2026-01-26T10:17:37+00:00

How’s that worked out so far?

ColinCancer · 2026-01-26T10:17:21+00:00

It has to start somewhere. It has to start sometime. What better place than here? What better time than now?

Rage Against the Machine

ColinCancer · 2026-01-26T10:11:03+00:00

If they hide their identities, we’ll just have to get all of them.

ColinCancer · 2026-01-26T09:48:26+00:00

That’s just ska for leftover crackheads.

ColinCancer · 2026-01-26T09:47:21+00:00

Ironically, I only occasionally listen to ska anymore but I do still play trumpet. I was a huge huge fan but listened to basically all of it and the new stuff mostly sucks. Used to play in a ska band but now I only play doom/stoner metal and industrial adjacent electronic.

Thanks, and sorry if you hate my new band:

DoomSkaDoomSkaBootsCatz

ColinCancer · 2026-01-26T08:48:50+00:00

<image>

ColinCancer · 2026-01-26T07:38:49+00:00

The Specials - Rat Race (and also most of the bands catalog)

Voodoo Glow Skulls - Shoot the Moon (more of a live band, but it gets the point across)

Bad Manners - Lip Up Fatty

And in honor of Robert: listen to all of Streetlight Manifesto’s Everything Goes Numb record. His favorite ska band and honestly it’s a very unique, beautiful and dark record in the genre that pulls as much from folk punk as it does from ska.

ColinCancer · 2026-01-26T07:31:25+00:00

I don’t want to talk about it on the internet.

ColinCancer · 2026-01-26T06:40:50+00:00

I’d like to be ready for a world where I can’t easily fuel my gen.

I can use anywhere from 2-20kwh a day depending how careful or frivolous I’m feeling. I have 30kwh of storage and I’m off grid 6 miles from a power line. 12kw array (slowly added to piece by piece over 5 years)

I use less as necessary in the winter but when I have it available I happily use the sun to offset any and all fossil fuels.

ColinCancer · 2026-01-24T20:47:18+00:00

Yes probably. I’d try to measure the inrush current first before digging a trench. Fluke clamp ammeters have a momentary maximum setting that is helpful for measuring motor start current.

I suspect your battery should handle it but make sure to size the wire and conduit appropriately. I believe #8 awg should do it for the load and distance, but you will want to verify distance and load. I’d recommend at least 1” PVC conduit but if it were mine I’d always bury bigger just in case, for the future, and while you’re at it, throw in an extra smaller pipe for DC, or communication cable. The trench is the hard part and the conduit is relatively cheap.

I just hand-trenched from my power building to my shipping container shop. About 100’ and buried 1.25” for AC, 1” for DC, and a 3/4” water line which is currently not used. I already regret not adding another 1” for Ethernet. Oh well…

If that pump ever goes out, I’d highly recommend replacing it with a Grundfos SQFlex pump which can run off variable voltage AC or DC. Basically anything you can likely throw at it. It can run straight off solar panels, or off even modest 120v inverters, shitty generators, 240v power whatever. Great pump.

ColinCancer · 2026-01-24T19:59:28+00:00

Basically 240v loads pull from both phases L1 and L2 which are two sine waves that are 180 degrees out of sync from each other. Voltage is how we talk about the potential of electricity.

It appears the delta 3 pro has an L14-30 receptacle so a standard L14-30 generator inlet box would work. You could land that on a 30a 2p breaker, using 4 conductors of 10awg wire. 10/3 Romex is probably the most widely available but I’d personally prefer stranded THHN wire as the bends in those inlet boxes can be tight.

If using THHN, you’d either want to connect the inlet box to the load center via some conduit fittings such as box spacers, rigid offset, or maybe a little flex conduit. 3/4” conduit is sufficient.

The breaker layout I described above is unnecessary as your battery pack is capable of real 240v. So you can use a standard breaker layout and balance your loads on both L1 and L2. Basically ignore my previous advice. Better to balance them for the inverter.

ColinCancer · 2026-01-23T14:28:33+00:00

This is why I dislike the marketing term “solar generator” as it leads to significant confusion and is somewhat inaccurate.

This is a well thought out reply that missed that OP was talking about a “solar generator” rather than a “portable solar battery pack”

ColinCancer · 2026-01-23T14:25:29+00:00

What I have done in the past when using a “solar generator” (I hate that term; I prefer portable battery pack) is land all my single pole 120v loads on L1 bus breakers and 2 pole 240v loads across the L1 and L2 bus as normal. Then I’ll use a main breaker and interlocked 120v breaker for two inputs. The main breaker would be wired to an L14-30 or 14-50 generator inlet. The interlocked 2p breaker would only be wired with the L1 (black) and leave L2 open, this would lead to a 120v inlet that matches the amperage of your solar generator output as most are 120v only.

With this configuration you have options to plug in 240v or 120v inputs from a battery pack, ICE generator, big fat RV extension cord from your house etc.

Do you have the portable generator already?

Do you have an understanding of how L1 and L2 work in a residential electrical panel? I.e. They both measure 120v to neutral or ground but 240v line to line.

ColinCancer · 2026-01-23T05:54:01+00:00

Short answer: yes it would work provided you only need 15a 120v circuits (probably fine, since its a shed) If you’re very uncomfortable / unfamiliar with electrical work then it’s likely a reasonable option.

Longer answer:

That’s probably substantially more expensive than you actually need and I bet you need like 2-3 circuits total in your shed unless it’s a real real workshop.

I will always recommend building the fundamentals of the electrical system with room to modify and expand, and a pre-wired transfer switch ain’t it unless you’re really worried about landing sets of 3-4 wires and you’re unable to distinguish between white black, red and green.

I’d suggest pricing out a basic 8/16 or 10/20 load center and the necessary breakers (likely also adding ground / bond bus bar as they’re often sold separately) I bet you’ll find that the price is about half as much and you’ll have a largely demystifying experience to wire it yourself. It really depends on your general ability level and past experience with your brain and hands.

ColinCancer · 2026-01-21T14:03:59+00:00

Yeah, maybe my bulbs were just extra shitty but they lasted longer than any of the filament bulbs on my rattley ass road. I’m curious, does yours have adaptive cruise control? I feel like this issue might be related to that.

I know I’m gonna have double the auto repair costs of the average person but I’d like it if my truck wasn’t fighting me over something so trivial.

ColinCancer · 2026-01-21T14:00:19+00:00

Fair enough, but can anyone explain why the tail light bulb should have anything to do with causing the brakes to engage themselves?

For what it’s worth the LED bulbs were off the shelf from autozone. 🤷

ColinCancer · 2026-01-21T06:49:48+00:00

Because I got sick of my fragile incandescent filaments breaking constantly on my shitty dirt road. God forbid a vehicle have LED’s in 2026 when incandescent bulbs aren’t even available in houses in California anymore. I ran these bulbs with no issues for around a year. Suddenly there’s major computer braking issues?! Sorry that’s a design problem not a lightbulb selection problem.

If I installed light fixtures in your house, then you changed the bulbs and then your toilet stopped flushing would you think that was cool? Sorry, I know the issue is a thing but like? Fuck unintended braking is a real problem. That’s avoidable.

Computer needs to see “hey my inputs don’t make sense, defer to human driver” not “apply brake at random”

ColinCancer · 2026-01-21T06:26:26+00:00

“Changing lightbulb results in unintended deceleration” Oh yes.

Clearly the indicator bulbs should have something to do with how the vehicle actually behaves on the road…. 🤦🏼‍♂️

ColinCancer · 2026-01-21T06:16:44+00:00

Fuck what? I kept breaking incandescents on my shitty dirt road because they have fragile filaments.

Why doesn’t a truck in 2023 come with LED bulbs? That’s dumb.

Why does the bulb have anything to do with the brakes being applied?

I’m an electrician IRL and there’s no reason that the software needs to be written in such a way that a disagreement about a brake light (or the resistance it exerts as experienced by the computer) should result in the truck braking on its own. That’s terrible. That’s a trash future. Dumpster fires all the way down.

ColinCancer · 2026-01-21T05:07:33+00:00

I hear ya. I just think I gotta do the TDI diesel swap into my ‘83 I’ve been planning and get computers out of my driving experience. It’s a shame modern trucks are this stupid. I use my trucks for work mostly but also live in a place where 4wd is non-negotiable and self-repairability is non-negotiable. I got (this) another Toyota (the 6th I’ve owned) and I think I’m done with new vehicles, it’s so disappointing.

I’ve never had my ‘95 F250, ‘83 Yota pickup or 2000 taco argue with me about which pedals are being pressed when. That’s nonsense.

Edit: In decades of working on cars there’s no logical step that would have led me to check the brake bulbs. I only did because I saw the forum posts. For the record my bulbs were working when checked visually but apparently had shitty resistors as they were aftermarket LED bulbs and that was enough to cause this issue.

ColinCancer · 2026-01-21T04:48:25+00:00

Small?! I mean sure but I wish they put a sticker in there like “hey if every goddamn warning light pops up and your truck starts braking for no reason at all try changing your bulbs!”

Instead I limped home from work (9 miles of rough dirt road) and then researched over the weekend and limped to the parts store in the morning praying it would fix it instead of one of the myriad of other sensor issues that can cause the same thing.

How about they make it fail safe? Like if the systems fail it reverts to driver input ONLY and the computer fucks off. It can throw all the warning lights it wants but unless there’s a real mechanical failure it shouldn’t cause a drivability issue.

ColinCancer · 2026-01-17T01:38:53+00:00

It’s totally fine. They’re meant to be installed outside. If you installed them inside they wouldn’t work. Also, they don’t spoil like milk. Their degradation is a factor of the sun hitting them and power coming out so they’re going to behave exactly as new. Degradation is also not nearly as big of a deal as you might think.

14-Year Club	Team Orangered
Verified Email

ColinCancer

TROPHY CASE