Please help me ! Getting no charge please help

[Adtl]

Redone no change
No amps just voltage
Cresent moon on display

 

[chrisski]

If the fuse is blown, the DMM will read 0 amps, but read colts fine.

Next step would be to measure something else for amps that puts out less than 10 amps. If that measures correctly the DMM nad fuseis good. If you don’t have something to measure, that’s where you take the DMM apart and ohm across the fuse. Short circuit is good. Open Circuit is a bad fuse.

First time I read amps with my DMM, my fuse kept blowing at much less than rated. I had to get a new DMM to measure amps.

You have a better DMM than the cheap one I had.

 

[MisterSandals]

Next step would be to measure something else for amps

Use a small flashlight battery. AA or AAA or C or D or 9V, all very easy and will show a couple amps.

 

[chrisski]

Use a small flashlight battery. AA or AAA or C or D or 9V, all very easy and will show a couple amps.

That is an amazingly simple tip that I did not figure out when Testing my fuses. Much better next step than taking the DMM apart!!

 

[Bud Martin]

Top right cable solder joint is a likely suspect. It's a dull gray color verses the other 3 solder connections that are bright and shiny.
You can measure the cable resistance from the diode cathode ( side with the gray band) to the far end of its cable. Or just re-flow the dirty solder joint, being sure adding more rosen core solder.

+1, also do the same on the other cable between the Anode of the diode and the far end of the cable.

 

[Bud Martin]

Put meter across diode to check and meter buzzed so guess ok
However if I put it across the plug ends it doesnt
Should it make a continuous circuit and buzz meter?
At my wits end here!!!!

it means you have open circuit in the wiring some where.
Edit: mean to say high resistance in the wire or connection.

 

[chrisski]

it means you have open circuit in the wiring some where.

Diodes stop flow of current one way, so it should be short in one direction and open the other.

 

[Bud Martin]

Diodes stop flow of current one way, so it should be short in one direction and open the other.

He should get the same result testing at cable ends since one end of the panel cables are connected to the diode, just think of the panel cables as the extension of the meter cables so he should see the same result when he put meter cables at the MC4 Male and Female end of panel cables. Right now OP has high resistance in one/ or can be both of the wire or connection.

 

[Zwy]

If I unplug leads at solar panel on roof it measure 17v
If I check the same lead ends in van it's still 17v
I attach to controller after battery is connected and it goes to 2v or 3v
Still has the cresent moon symbol by panel as seen
Really at my wits end !!!!

The reason why is you are measuring open circuit voltage. Once a load is placed on the circuit, the point of failure has too much resistance and voltage drops.

Normal conductance tests using an ohmmeter measuring resistance won't help either.

What you need to do is disconnect any connectors, then apply 12V at one end with a ground on the other wire, then apply a load such as a headlamp or electric motor and measure the voltage drop across each section of wire. Basically, you attach the positive meter lead at source and the negative meter lead at the load on the positive side of the circuit; for the ground side you attach positive meter lead at the load and negative meter lead at the ground connection. Explained in this link. https://support.alldata.com/sites/main/files/file-attachments/voltage_drop__test_122718.pdf

This is the correct way to perform a voltage drop test.

If the wire checks out, then you need to look at connections. Use a back probe pin like these: https://duckduckgo.com/?q=back+probe+pin&t=chromentp&atb=v255-1&ia=web

Or find some sewing T pins which I use daily. https://duckduckgo.com/?q=t+pins&t=chromentp&atb=v255-1&ia=web