RealPro battery charger repair

Our battery charger has snapped where the SB-50A meets the yellow piece. Is there a way to repair this?

Those yellow things are just inline fuse holders. You could splice any low voltage fuse holder in its place.


You can’t really repair it but you can cut it off and put on a new crimp for the SB-50, you could also extend the wire with a solder splice or other methods if you need. Finally, if you want to keep using a fuse andymark sell them.

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I’m tired of intermittent connections at the fuse and broken fuses with those yellow inline holders.

I’m thinking of replacing them all with something like these. Also 30A fused. Thoughts?

MCIGICM 12 AWG Inline Fuse Holder…

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We were similarly frustrated and did exactly that. We purchased these, which look basically the same. We haven’t had any issues since.

Do you use 30A, or lower?
Thinking of buying another RealPro (one of ours is ~10 years old and showing its age), but have had to do a lot of replacing of wires at the fuse connections over the years. Might swap all wires over to these in-line fuses.

We have been disappointed in the quality of the RealPro’s after having issues with both of ours. Both of our units had their innards completely separate from their shells, so they have literally been held together with packing tape for years (these date from 2016). Shortly after, one of the units’ LEDs stopped working consistently, so even though it seems to function it’s impossible to know what it’s doing; that one also had fuse holders disintegrate as in this thread. It’s now “retired” as we don’t trust it, and the LED issue is completely unfixable since these things are “potted” inside.

If you decide to look at alternatives, there are a number of decent options out there (consult many threads here) - we’ve started using Noco Gen5x1 and like them pretty well, FWIW. But there are lots of choices depending on your preferences and budget.

While I will admit the original fuse holders are rather annoying, we do sell replacements if you want.

What SOC does that NOCO charge to? We switched to them back in like 2016 but gave up and went to the RealPro because the NOCO just seemed too “gentle”. Like it would just barely get to 100% SOC, versus both our old and new ones that really hammer them up to 130%. I know it’s all “surface charge” and theoretically minimal, but this is a competition where every watt counts over the 2 minute match with a battery fresh off the charger.

That 130% really does not mean much of anything. It is not 30% extra charge - it really is a surface charge that dissipates as soon as you put a load on the battery. Here’s a discharge graph from a break-in cycle tonight:

This battery started at around 110% fresh off one of our Noco’s, but notice that it immediately drops by half a volt as the surface charge is used up; and this is at a mere 7.5A load, nothing close to what a robot would be drawing. If your initial SOC is nominally 130%, the initial voltage drop is larger but just as fast.

Yeah, that 130% charge level reported by Battery Beaks is completely meaningless. I’ve seen batteries with only 10% of their original capacity report 130%.

I checked today and we are using 7.5A fuses. I don’t recall why we selected that particular amperage.