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Renogy 20A Charge controller suddenly shows no battery life

Skyno

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Sep 16, 2021
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I was testing small electrical items (light, water pump, etc.) through the load on a Renogy 20A charge controller. Lights tested fine but when I tested the water pump the fuse blew and suddenly the Charge Controller went from 100% to 0% battery and displayed Error 1 Battery Over-discharged. I understand that the CC is not an accurate measure but I thought it was still unusual to immediately go from 100 to 0. There was sun out and I was hoping it would quickly show a re-charge, but the controller was displaying no charging and after a little while it started to blink the empty battery signal, and then a bit later a blank screen. The batteries still have power since the inverter is working but the CC is not responding at all anymore. I have been looking online for answers but can't figure out what is going on. Any thoughts? Thank you!
 
Lights tested fine but when I tested the water pump the fuse blew and suddenly the Charge Controller went from 100% to 0% battery and displayed Error 1 Battery Over-discharged.

What fuse? If it was between the battery and the charge controller, of course the controller will say the battery is discharged.

How was the pump connected? To the auxiliary output of the charge controller or the battery? If the former, it is not designed for high current loads, just a few LED lights or similar.
 
Thanks for the response. The fuse that blew was between the device (water pump) and the charge controller. I was using the auxiliary load output just to test a few small load devices to make sure everything worked individually before hooking it all up. The 1.5A LED lights and 3A fan tested fine but testing the 2.5A water pump is what caused the issue. The charge controller is still showing 0% and no charging and E1 over discharge error, but battery is still powering the inverter.
 
The pump startup current may have been too much. I would try disconnecting everything (panels first, then battery). Then reconnect the battery and then the panels. If it is still dead, it may be fried from the pump load.
 
Thank you again for the response that’s what I was afraid of - I got my hands on a meter and the voltage on the battery reads 13.1 on both the battery itself and connectors on the CC. I tried disconnecting and reconnecting the charge controller last night when there was no sun and unfortunately it is still showing no charge.
 
Although it is surprising because the specs on the water pump show 2.5A max
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The startup current on motors can be much higher than the running current, especially if they are loaded down when starting.
 
Last night when you disconnected the panels did you disconnect the battery from controller as well? If not you should try that-leave it disconnected for a few minutes...
 
The startup current on motors can be much higher than the running current, especially if they are loaded down when starting.
Good to know thank you - I didn't realize that a water pump with a spec of 2.5A max could pull a significant amount more than that on startup - since the pump recommends using a 3A fuse wouldn't this blow the 3A fuse all the time on startup if this was the case?
 
Last night when you disconnected the panels did you disconnect the battery from controller as well? If not you should try that-leave it disconnected for a few minutes...

Yes I disconnected everything for a few minutes - display was totally blank
 
since the pump recommends using a 3A fuse wouldn't this blow the 3A fuse all the time on startup if this was the case?

Not necessarily. That current surge can be very brief (not enough to blow the fuse). But since you said the fuse did blow.....
 
Here’s another interesting finding - even though the charge controller is still showing E1 error and showing that battery is at 0% and providing 0 charge, It still seems like the battery is being charged I drew a load from the inverter for a few minutes verified the voltage drop and sure enough a few minutes later it had gone back up
 
Here’s another interesting finding - even though the charge controller is still showing E1 error and showing that battery is at 0% and providing 0 charge, It still seems like the battery is being charged I drew a load from the inverter for a few minutes verified the voltage drop and sure enough a few minutes later it had gone back up
You have the exact problem I have except on a 40A version. If it's under 2 years old call up Renogy and get it replaced and tell them what all you have done, they will ask for pictures of the battery voltage, solar panel voltage than the unit itself showing the problem. If you get a response back after getting that sent to them you got further than me as they have yet to get back with me over month later.
This also can be caused from crossing the battery wires too.
 
I drew a load from the inverter for a few minutes verified the voltage drop and sure enough a few minutes later it had gone back up

What type of battery? FLAs will "recover" quite a bit after a load is removed.
 
You have the exact problem I have except on a 40A version. If it's under 2 years old call up Renogy and get it replaced and tell them what all you have done, they will ask for pictures of the battery voltage, solar panel voltage than the unit itself showing the problem. If you get a response back after getting that sent to them you got further than me as they have yet to get back with me over month later.
This also can be caused from crossing the battery wires too.
Good info - you are spot on this is exactly what they asked for and I sent it today - that is discouraging that they haven’t responded to you though
 
You have the exact problem I have except on a 40A version. If it's under 2 years old call up Renogy and get it replaced and tell them what all you have done, they will ask for pictures of the battery voltage, solar panel voltage than the unit itself showing the problem. If you get a response back after getting that sent to them you got further than me as they have yet to get back with me over month later.
This also can be caused from crossing the battery wires too.

Follow up question - I was curious if you have any other sort of battery monitor hooked up to your system (I currently don't) and if so, if that is reading correctly? Thanks!
 
Follow up question - I was curious if you have any other sort of battery monitor hooked up to your system (I currently don't) and if so, if that is reading correctly? Thanks!
I put a multi meter on mine and it showed 12.7 on the battery, 0 volts coming in from charge controller and 40 plus volts from the panel coming in, so I know it ain't my end. Thankfully it's just to maintain batteries I have around here for equipment, I have a Midnite 150SL running my home.
 
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