shore power charger

[John Taves]

Dacien, I apologize for bothering you, but can you confirm that the Mean Well RSP-1500-27 Enclosed Switching AC-to-DC Power Supply will work to charge a 24v LiFePo4 pack?

Your manual mentions the RSP-750-27 so I am confident this is fine, but I wanted to understand the concept.

I can see that I can set the voltage, and it has remote on/off, but doesn't it have to limit its current? My understanding was that the lithium batteries have very low resistance so wouldn't this deliver all it can and thus wouldn't it trip it's own amp limiter? Don't we need some sort of amperage limited thing?

Thanks

jt

[Dacian Todea]

John,

The spec is a bit strange for the RSP-1500 it says it has constant current limiting but it says it will shut down in 5 seconds meaning is node designed to be used as a charger https://www.mouser.ca/datasheet/2/260/RSP-1500-SPEC-1511951.pdf

The RSP-750 is constant current so that means when connected to a battery it will push that spec current in to battery charging at around 750W unless you set a lower current limit 40% to 110% possible.

Why will you need 1500W charging ? how large is your battery pack ?

It may be just a wrong spec for the RSP-1500 and it may work the same as RSP-750 but I have no idea but likely RSP-1500 will not work. 

[John Taves]

I will have a 280ah 24v pack in my RV. I don't need the 56a, but it was 50% more so why not? The only reason to get the charger is for the situation where I suffered no sun for a few days and wanted to bump the batteries up. I figured that the faster I charge, the sooner I can unplug or shut off the generator.

I agree with your assessment. I just assumed the two were the same, but different ratings. I have since reviewed both data sheets and you are correct. The RSP-1500-27 does not have a programmable current limit like the RSP-750-27.

It seems that you have to supply a DC voltage of 5v at a specific pin to tell it you want 100% of the rated current, along with removing a jumper. Very cool.

Thanks for that and thanks for confirming my understanding of charging the LiFePo4s.

jt

[Flint Smith]

(I see that this was 5 years ago. I'm adding this for anyone else searching RSP-1500 in the future.)

If you need massive current, there's the RSP-1600 which does have programmable current. 

Current can be set down to just 20% of rated output so you could substitute it for an RSP-750.  

Unlike the RSP-750, you can put additional units in parallel.  When we get solid-state batteries, everyone will want one (or two).

Dirt cheap and plentiful in the 24-30V.  12-15V is tougher.