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NEW DIY system battery with meter problem

waylotul

New Member
Joined
Jul 26, 2021
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15
I built this system and it works. I wanted to add a Renogy Battery Meter RMB500

Per instructions for the Renogy Battery Meter:

I put the shunt inline with the Negative to the battery on B-
I put the charge controller and inverter on P-
In that configuration, the battery meter flashes all the time and shows discharging while the charge control shows its charging.

IF I move the SCC- to the same post B- as the battery, the meter appears to work properly.
Renogy support was not really able to help me on why when wired correctly with SCC- on P- it constantly flashed.
They suggested to contact EpicSolar about the 40 MPPT controller compatiblity with the Renogy Battery Meter.

Please also advise your opinion on best practice in my circuit design.
Maybe that is the problem here?

You can see how I consolidated my connections for all positives directly on the 410W Inverter. I remember in basic circuit design it doesnt matter if they are all on the inverter or at the battery + post. This gives me only 2 leads to the battery and 2 for the single solar panel its semi-portable.

IF only someone can advise why my battery meter seems that it works correctly when wired with the SCC- connected to B- instead of P- as directed by the Renogy manual.
Please help!
Thanks in advance.
 

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Welcome to the forum.

I was replying while you were editing. The original pic of your wiring looks correct to me if the "top" terminal of the shunt is P- and the "bottom" terminal is B-. Your SCC and inverter negatives should both connect to the P- terminal.

Your current pic with the SCC negative going to the B- terminal of the shunt shouldn't work. In that config, the SCC shouldn't register as a charging source.

Can you please post pics of the battery monitor display while charging in each wiring configuration?

Also, it looks like the inverter switch is in the "on" position with a green LED lit and a lot of devices plugged in. If your loads exceed what the SCC is supplying, the monitor will show the net draw out of the battery bank.
 
THANKS for looking at my Frankenstein RIG!!!

OK I just photoshopped the 2 readouts

controller Read out AND the Battery Meter read out

1 renogy solar 100 Watt panel. 30FT leads

The load is 110v
2 IP WIFI cams. .5 amps each
1 smart switch ( currently off) w/ LED bulb 40W Equivalent
1 Alcatel Cellular WIFI Hotspot connected. 1 or 2 amps (I will edit this)


This is live
full cloudy sky coverage at the moment.
 

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THANKS for looking at my Frankenstein RIG!!!

OK I just photoshopped the 2 readouts

controller Read out AND the Battery Meter read out

1 renogy solar 100 Watt panel. 30FT leads

The load is 110v
2 IP WIFI cams. .5 amps each
1 smart switch ( currently off) w/ LED bulb 40W Equivalent
1 Alcatel Cellular WIFI Hotspot connected. 1 or 2 amps (I will edit this)


This is live
full cloudy sky coverage at the moment.
I changed the configuration showing the CSS-neg going to the shunt on P-
I made a video after a minute or so in the sunlight the Battery meter slowly strobes and the hours remaining dropped to 31 then to 16.

Now in shade no direct sun I get the last picture.
 

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The load is 110v
2 IP WIFI cams. .5 amps each
1 smart switch ( currently off) w/ LED bulb 40W Equivalent
1 Alcatel Cellular WIFI Hotspot connected. 1 or 2 amps (I will edit this)
The cams are 60W each: 120W x 24h (2889Wh per day!)
40W equivalent is maybe 6-8W
hotspot 2 amps is 240W.

This is a LOT more power than your 100W panel, harvesting sun for maybe 5 quality hours a day (500 watt hours) and hope to produce.

What, what was the question?
 
I changed the configuration showing the CSS-neg going to the shunt on P-
I made a video after a minute or so in the sunlight the Battery meter slowly strobes and the hours remaining dropped to 31 then to 16.

Now in shade no direct sun I get the last picture.
With your configuration set to all negatives going to P-, turn off your inverter while you are charging. The meter should switch from showing negative current to positive. As far as I can tell the monitor package is working properly. Your loads were just pulling more out of the battery than your SCC was putting in.
 
The cams are 60W each: 120W x 24h (2889Wh per day!)
40W equivalent is maybe 6-8W
hotspot 2 amps is 240W.

This is a LOT more power than your 100W panel, harvesting sun for maybe 5 quality hours a day (500 watt hours) and hope to produce.

What, what was the question?
Oh wow, OK i never thought these little cams pulled that much juice I actually never calculated my energy usage and really need to examine that. The load is a static number of devices so it should be a known value to calculate total usage. This energy usage awareness is another component that I need to begin to understand. I have no clue how much my panel is capable of.

I have advise that I am making simple mistakes. These devices are low voltage output

My actual load on the 110 inverter are rated as follows:

2 IP cameras - 5v 1amp 10 Watts Combined
1 Cell Router - 5v 1amp 5 Watts
1 Smart Home Controller - 12v 1 amp 12 Watts
1 LED light bulb via Smart Switch 110V currently off but used to look at the system readouts.

27 Watts X 24 Hours = 648 WattHours?
This has to have load 24/7 for the security system off grid.
I thought average sun would be about 6 hours a day

any advice is appreciated.
 
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With your configuration set to all negatives going to P-, turn off your inverter while you are charging. The meter should switch from showing negative current to positive. As far as I can tell the monitor package is working properly. Your loads were just pulling more out of the battery than your SCC was putting in.
I did as you advised. I have images of the system in both conditions Inverter is ON and OFF
 

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Why only 7 hours on time remaining with the inverter off do I just not understand?
why are the arrows pointing UP like power is going out? or is it charging up now.
such a novice right?
 
Why only 7 hours on time remaining with the inverter off do I just not understand?
why are the arrows pointing UP like power is going out? or is it charging up now.
such a novice right?
That's 7 hours remaining until fully charged at present charging rate.
The up arrows indicate filling up the battery. Down arrows indicate depleting the battery.
 
That's 7 hours remaining until fully charged at present charging rate.
The up arrows indicate filling up the battery. Down arrows indicate depleting the battery.
Thanks for the clarification. I thought "up" arrow was electron flow out of the battery.!!

I have added two more images.

The EPEVER 40MMPT shows the Renogy GEL 110ah is now full (6 hours Direct Sunlight). Two lights flashing.
I RE-Calibrated the battery monitor. to ZERO then 100% per instructions.

Here goes two images of the system with the inverter OFF and ON after Meter calibration.

I think I see the panel pushing 69 Watts at almost 5 amps with the load/inverter off??
and 52 watts at 3.2 amp output from the panel? with the load?

I just not sure what Im seeing to understand.
 

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Oh wow, OK i never thought these little cams pulled that much juice I actually never calculated my energy usage and really need to examine that. The load is a static number of devices so it should be a known value to calculate total usage. This energy usage awareness is another component that I need to begin to understand. I have no clue how much my panel is capable of.

I have advise that I am making simple mistakes. These devices are low voltage output

My actual load on the 110 inverter are rated as follows:

2 IP cameras - 5v 1amp 10 Watts Combined
1 Cell Router - 5v 1amp 5 Watts
1 Smart Home Controller - 12v 1 amp 12 Watts
1 LED light bulb via Smart Switch 110V currently off but used to look at the system readouts.

27 Watts X 24 Hours = 648 WattHours?
This has to have load 24/7 for the security system off grid.
I thought average sun would be about 6 hours a day

any advice is appreciated.
I wanted to update my thoughts on usage at night mostly 12 hours a day not 24 hours a day so my load is probably half on a sunny day? just during overnight? Thanks for any advice
 
Just FYI: Inverter efficiency also comes into play, the input power to the Inverter will be higher than the output power so you have to factor that in + system loss to get the run time of your system.
 
I ran ALL the loads last nite too this first pic after dark.
My load was under my estimate at a about 20 Watts.
I guess the devices are not pull Max rated power
real usage is actually lower!!! wow!

I took the second pic this morning at dawn after turning off the LED light.
I used 85 percent capacity running all devices including the light.

Thanks for all the help here I feel more confident installing this now!!!
 

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