Lightobject.com Support Forum

Hi,

I'm using a JLD404 with a set of solar panels. I'd like to measure both voltage and current. This is the setup below.
(If it isn't clear, the panels are 14v 250w total. I also purchased the 20A 75mv shunt.)



Question is: is the setup as simple as I've drawn? All I really want to measure is Voltage, Current and accumulated Ah over a period of time.

Have I got it right?

Thanks!

I called the company and they did a great job confirming that my drawing will work. The only thing to change slightly, is that Ground to the number #2 pin will come from a grounding source that is directly to the battery, and not through the shunt as drawn.

I’ll report back and confirm once I’ve got it installed.

Adam:

There is a little missing on your diagram. You forgot to take input from the battery which is by default #6. Without it, you can't read voltage on the battery. The diagram you're showing will just power up the meter without voltage but the current only

I did post a manual on the Manual section. Download it and go through it before doing installation.


Marco

Yeah,

I'd already posted the picture before I talked to you.

Here's the new diagram. I hope to get to the project soon. I'll report back when it's complete.

Ok, I've got it installed but am a little confused by the numbers.
I changed V-Sn to 100V.

These measurements are about 4 hours into the day.

Ah - 3.381
A - 2.312
V - 5.2

Questions;

1. Why does V show 5.2? It should be something like 13.0 as this is the number off my Xantrex Battery Monitor.

2. Amps don't make sense. I've got 250 watts of solar. I'm surprised by any number over say, 18 amps.

3. My batteries (total 770Ah AGM), are currently at 77%. My Xantrex monitor is showing that the batteries are at 13.0 V and accepting 10.2 Amps. These numbers don't look anything like the JLD404 is showing.

Can you help?

Thanks,

Hello Adam,

You should put terminal #6 to the battery instead of the terminal bar.

Here is the setting that i think is to properly set up the AH meter.

A-Sn->75mV since you measure more than 5A
APvH->20A you may need to adjust decimal point to get 20A

V-Sn->100V
UpoH->100V

Please let us know if it works.

Ok,

We're getting close... But there's still an issue.

First off, when the boat battery charger is off, the system works perfectly!
The trouble arises when the battery charger is turned on.

At one point today these were the readings;
Ah 65.03
Time 8hours
A .15 (the sun had just gone down)
V 12.5

Then I turned on the charger and these were the readings;
Ah 61.22.
Time 9hours.
A -3.57
V 13.8

So, I've got something causing this setup to run backwards. Is there a way the meter can work correctly and only measure Solar Output, without some elaborate diode install?

Here's the current software settings;
A-Sn 75mV
APvL 0.000
APvH 99.00
Adot 2
U-Sn 100V
UPvL 000.0
UPvH 100
Udot 1
FILt 1

This may be beyond the capability of the meter.
Got any ideas?

Thanks,

APvH 99.00 should set to 20 because you are using the 20A 75mV shunt

The negative sign of current reading may caused by the current flowing backward because the voltage generated from the panel is less than the voltage of the battery at sunset.

I had it set to 20A, but after the first time the charger was turned on, the Ah went to -EEE.

The charger puts out up to 150A and while I agree that the 404 meter and shunt is picking up on current flowing "backwards", I'm unsure what to do about it.

Would a diode be appropriate for one of the shunt wires? Or do I need a Diode on one of the main wires? I'm concerned about a voltage drop on the main 6 gauge wires.

Any ideas?

Any very smart electronics people out there?

Anyone?

Bump

Why would you set 20A when charging current would flow over it? EEE.E = overload

It is a safety to install a diode on each panel to avoid back-flow. Use Schottey diode with low potential drop (0.3~0.4V). It is ok for such low drop as as standard 12V panel may output as high as 20V during peak time. You just need to install One diode and I'll do it on the positive terminal .

I helped one folk to build his duck house: viewtopic.php?f=12&t=1348



Marco

I put it back to 22A. I made it more because of the -EEE caused by the charger to the batteries
putting out 150A at night when the solar panels aren't working. But that doesn't really fix the problem.


The solar controllers themselves stop the current "backflow" from damaging the solar panels.
So, is it the shunt that's picking up the backflow?

If I put in 1 diode, where exactly does it go in the diagram? And do I need one rated for over 22A?

Thanks,

Also,

What exactly does the power to pin 6 do?

Can I get some help on these last two issues?

Thanks

Bump