Renogy 2000w not working

[tx2sturgis]

With all due respect...


The elephant in the room is:

You have the wrong batteries for that charger,

or,

you have the wrong charger for those batteries.

The system seems mismatched, overly complex, and prone to future problems.

It might be time to re-think this.

 

[Weight]

The problem is the homemade battery management. It sounds much too complicated than what you need. But i can't really trouble shoot from here. There should be a way around this problem.

 

[VanKitten]

Yes, I have been looking for a work around.

It is not totally a "home made" BMS. I got the ideas and process (devices) from the electric car manufacturers. Since my system is 400AH...the commonly available BMS will not handle an system that big.

Talking with Renogy is pretty much a waste of time. I don't get to actually talk to the engineer...just a tech that puts me on hold for long periods while he goes and asks a question of the engineer.....usually to wrong question. After hours of that (mostly spent on hold) I quit wasting time with them.

I may not be able to ever run this as the charger. I am thinking I might just replace the unit completely. Get an inverter and a charger as two separate devices. Then I can wire them and run the separately too.

But..one big advantage to me has been learning this system in excruciating detail!

 

[Weight]

Yes. That was my final decision. I have a marine charger, a solar controller, and an inverter. All separate devices and different manufactures. I don't have experience with many LiFePo batteries and those were only 36v/10ah. I did study a lot, before I settled on GC2 lead acid. I was very tight for money at the time. The BMS I have seen, are small devices that connect across the cells of the battery. More cells more devices.

 

[John61CT]

The LFP industry is making billions selling "systems", packaged with proprietary BMS designed for a specific pack size.

Little profit is made on the bare cells market, and a very flexible and robust generic BMS, what I call "open hardware" will eat into the systems market.

All the hobbyist attention is on EV usage, which high voltages and huge current rates "push the shoulders", require active cell balancing and users have very low expectations for longevity.
With much gentler low rates used as House bank storage, e.g. 30-100A continuous, 300A momentary if cranking a starter, no active cell balancing is required, and that is the main focus for most BMS out there, and leads to failures from complexity, usually can't be disabled.

So for DIY BMS, that leaves LVD & OVD protection, and temperature in some contexts.

The sensor/relay device doesn't **have to** handle high amps, just trigger a HD solenoid, but yes that adds another layer of complexity.

 

[VanKitten]

JIm,

Yes, the learning curve is steep. The complexity is a one time learning effort.
The single biggest issue I didn't have the up front smarts to avoid was the big battery bank.

Once over 250 amp...everything got lots beefier (think industrial) and pricier.

I understand BMS functions very well. The balancer were the first installed. The contactors were next....and the temperature sensors.

The wrinkle is the redundant relays in the Renogy inverter/charger. Instead of being really smart and using the power source inherently in the function being performed....the device relies only on DC Power for itself. So, even though the 110 power is available and driving the charge function....the dumb device does not use that already available power source!

Ok, I am past that now. Just going to install a separate charger and call it a day.

I think I could write a book on this adventure in LiFePo4 installation.
Even with all the issues I have had to over come..I do not regret the choice. Just the size.

 

[John61CT]

Size usually refers to AH storage capacity, I assume you're talking about current rates being high?

> Once over 250 amp...everything got lots beefier (think industrial) and pricier.

This is a House bank right, not EV propulsion? Are you using the bank to crank your starter? Winches? If not, then IMO you don't need to size for that high a rate. How large a bank? What's your biggest charge source.

> The balancer were the first installed.

I strongly advise against fulltime balancing, solving a non-existent problem, more likely to create problems.

Is there a build thread somewhere linking to sources for these various devices?