circuit breaker spark

[ohmboy]

Hello, just got lucky that nothing burned down but I wanted to check the amps on my system because the BMS is not showing the charge amps only discharge. So what I did is put my multi-meter probes in the input side screws and as soon as I touched the meter positive probe to the positive screw on the circuit breaker, it sparked!!!
I put the multi-meter on 10A and put the positive lead to the 10A port.
I am now afraid to check the amps.
Where should I check the amps coming in from the solar charge controller?
And did I plug in my multi-meter properly?

Victron 100 | 30 SmartSolar Charge Controller
24v 105ah LiFePO4 battery





thanks

 

[BarracudaBob]

I had a similar experience. I wanted to blame the breaker but after trying a few thing I found a crimped on wire feral sold the issue. I am perusing a come commercial bullet br4eaker resolution

Battery DC circuit breaker

Just got this little gem in the mail. The idea is to use it for the battery, and as far I understand it takes a non-polarized MCB for that. I want to test it to see if it's indeed a non-polarized MCB. Figured maybe I could use two 100W panels in parallel with a combined Isc of 12A and then...

diysolarforum.com

 

[robby]

I am not sure if you are saying that you put the Meter across the DC voltage +/- while the meter was in Amp mode? If so that was a direct short of the Meter and the meter either blew a 10A fuse or died if it had no fuse.
Your negative probes tip has burned off completely!

Assuming you had it inline with the positive terminal then you still would have had issues as the Meter can only handle 10Amps. Unless the load was less than 10A the meters fuse also blew.

Please clarify exactly how you had this hooked up.

 

[ohmboy]

I had a similar experience. I wanted to blame the breaker but after trying a few thing I found a crimped on wire feral sold the issue. I am perusing a come commercial bullet br4eaker resolution

Battery DC circuit breaker

Just got this little gem in the mail. The idea is to use it for the battery, and as far I understand it takes a non-polarized MCB for that. I want to test it to see if it's indeed a non-polarized MCB. Figured maybe I could use two 100W panels in parallel with a combined Isc of 12A and then...

diysolarforum.com

Where can I safely check the amps coming in from the solar charge controller?

 

[ohmboy]

I am not sure if you are saying that you put the Meter across the DC voltage +/- while the meter was in Amp mode? If so that was a direct short of the Meter and the meter either blew a 10A fuse or died if it had no fuse.
Your negative probes tip has burned off completely!

I placed the positive probe of the meter on the positive screw of the circuit breaker, then put the negative probe of the meter to the negative screw of the circuit breaker. I did not put the meter across both screws.

Assuming you had it inline with the positive terminal then you still would have had issues as the Meter can only handle 10Amps. Unless the load was less than 10A the meters fuse also blew.

Victron app was showing 4.5A so I thought it was safe. Meter seems to still be working.

 

[robby]

I placed the positive probe of the meter on the positive screw of the circuit breaker, then put the negative probe of the meter to the negative screw of the circuit breaker. I did not put the meter across both screws.

Huh!
If that is what you did then you did put it across the Positive and Negative.
When you put the positive probe into the Amp connection on the Meter it is putting both probes across an Internal Shunt that is basically a short circuit. The moment the Probes touch Positive and Negative the meter is going to short out and either blow a fuse (if it has one) or blow itself up.
The meter may still be working but I doubt that the Amp side of the meter is working. Open it up and see if you see a 10Amp fuse inside.

You need to be using a clamp on Meter that can read DC Amps if your going to be working on Solar.

Victron app was showing 4.5A so I thought it was safe. Meter seems to still be working.

 

[ohmboy]

If that is what you did then you did put it across the Positive and Negative.
When you put the positive probe into the Amp connection on the Meter it is putting both probes across an Internal Shunt that is basically a short circuit. The moment the Probes touch Positive and Negative the meter is going to short out and either blow a fuse (if it has one) or blow itself up.

Ahh, ok. I will not be doing this again!
Should I replace the circuit breaker?

The meter may still be working but I doubt that the Amp side of the meter is working. Open it up and see if you see a 10Amp fuse inside.

I will open it up and see if the fuse has blown.

You need to be using a clamp on Meter that can read DC Amps if your going to be working on Solar.

Next purchase will be a clamp on Meter. I have one on the wish list on amazon.


thanks again.

 

[robby]

Ahh, ok. I will not be doing this again!
Should I replace the circuit breaker?

I would mainly because the Terminal screws head is pretty bad looking. It might be easier to just replace it now then have an issue one night and you cannot get the terminal loose.

I will open it up and see if the fuse has blown.

Next purchase will be a clamp on Meter. I have one on the wish list on amazon.

Which one?

thanks again.

Your Welcome.

 

[ohmboy]

I would mainly because the Terminal screws head is pretty bad looking. It might be easier to just replace it now then have an issue one night and you cannot get the terminal loose.

I will put one on order today.

Which one?

I am looking at this clamp meter. It shows that it can measure 40amps DC up to 400amps. Amazon clamp meter

 

[BarracudaBob]

I will put one on order today.


I am looking at this clamp meter. It shows that it can measure 40amps DC up to 400amps. Amazon clamp meter

There are many hall effect DC clamp meters out there. It is a must have. I also have a Victron shunt and solar assistant so I can look at the graph. I almost missed it until I looked at SA. Clamp meters are great if you are right there and now.

 

[ohmboy]

There are many hall effect DC clamp meters out there. It is a must have. I also have a Victron shunt and solar assistant so I can look at the graph. I almost missed it until I looked at SA. Clamp meters are great if you are right there and now.

What is SA?

 

[Quattrohead]

Oh my, many of us have done that. It is a right of passage
New shorts, hit Amazon and off you go again.

 

[ohmboy]

Oh my, many of us have done that. It is a right of passage
New shorts, hit Amazon and off you go again.

Ok, I'm glad that it's not just me.

 

[BarracudaBob]

What is SA?

Solar Assistant or what ever software that works for you to see history

 

[SomethingAppropriate]

Next purchase will be a clamp on Meter. I have one on the wish list on amazon.

There are many clamp meters but not many that work with DC. I wanted a local one and had to go to 4 stores.....

 

[ohmboy]

There are many clamp meters but not many that work with DC. I wanted a local one and had to go to 4 stores.....

I really have to read the descriptions for the ones online. Most are rated for AC.

 

[Hedges]

Ok, I'm glad that it's not just me.

Sure, I used my Fluke with 10A range to measure current from 480VDC 7A string of PV panels.
No problem, right?
Well, they were connected to the input capacitor of my inverter. Blew the 11A 1000V fuse.

Another time I connected an inverter with 480VDC on its capacitors to another inverter, reverse polarity. Dumped the capacitor charge into reverse-polarity diode and blew fuses in combiner box. A comms module in the second inverter didn't work after that (didn't know if it ever did), but got replaced under warranty.

I bought Harbor Freight Aims 1000A clamp meter for $100.
Features include 1000A AC/DC, 10 mA resolution (on lower scale), AC inrush current.

check all panels are connected and working on fronius 27kw

we have a Fronius 27kw inverter connected to the grid with 90 x 375w jinco panels. The installer is no where to be contacted anymore. All this time, the inverter was not connected to the internet as there was no internet close to that building. Now I have connected the inverter to the internet...

diysolarforum.com

 

[Brett V]

I have one of these and a $400 Fluke meter. They both read the same.

https://a.co/d/bHHWxT2

 

[ohmboy]

Huh!
If that is what you did then you did put it across the Positive and Negative.
When you put the positive probe into the Amp connection on the Meter it is putting both probes across an Internal Shunt that is basically a short circuit. The moment the Probes touch Positive and Negative the meter is going to short out and either blow a fuse (if it has one) or blow itself up.
The meter may still be working but I doubt that the Amp side of the meter is working. Open it up and see if you see a 10Amp fuse inside.

You need to be using a clamp on Meter that can read DC Amps if your going to be working on Solar.

Yes, it looks like the glass fuse is blown. The continuity test failed and I am unable to tell if the filament inside is cut near one of the ends. I will have to use my CEN-TECH that I got for free at Harbor Freight.

 

[Robert Ibe]

I found a crimped on wire feral sold the issue. I am perusing a come commercial bullet br4eaker resolution

Could someone translate this please.

 

[robby]

Yes, it looks like the glass fuse is blown. The continuity test failed and I am unable to tell if the filament inside is cut near one of the ends. I will have to use my CEN-TECH that I got for free at Harbor Freight.

I suspected as much.
The fact that is was able to burn off the tip of the probe faster than it burned out the fuse is surprising.
I would not trust that meter for reading Amperage again unless you can reference it against a new meter and verify it's reading right, meaning nothing else inside of it got fried.
Yes it is a right of passage and it has happened to me with a low cost meter. After that incident it never read current properly again. It has also happened again with an expensive Fluke meters but in all cases the fast acting fuse saved it.
Fluke meters are fairly bullet proof.

 

[robbob2112]

Ahh, ok. I will not be doing this again!
Should I replace the circuit breaker?


I will open it up and see if the fuse has blown.


Next purchase will be a clamp on Meter. I have one on the wish list on amazon.


thanks again.

When you buy one get one with an 'inrush' setting.

 

[ohmboy]

When you buy one get one with an 'inrush' setting.

Ok, I will look for that. Thanks!

 

[robbob2112]

edit - DC inrush - that means it has a high sample rate to catch the leading edge. For Ac it doesn't need the high sample rate - I found several on amazon that do it for around $100ish ... or you can get the Fluke-393 FC meter for $900ish Or the Fluke-375 FC for $350ish much less if you trust aliexpress

NOTE - I love Fluke meters and they are wonderful, but expensive and intended for folks that use them all the time on the job - Bulletproof as mentioned above and they cost it.

But - if you look at the specs on the Fluke and compare it to the $100 version you will see the cheaper meter is good enough for anything a DIY person is going to do. The extra accuracy is only good on a test bench when it matters. In the field it doesn't matter if you are .1 amps off when measuring 100amps.
The higher sample rate means you chops the incoming voltage waveform into more parts and then does averaging so you get a more accurate reading. This is really more important than the number of digits on the screen or the stated ± accuracy.

 

[robbob2112]

Could someone translate this please.

Chatgpt says -

You
the topic is a DC breaker with a burned contact on one side translate this to what the user meant?
I found a crimped on wire feral sold the issue. I am perusing a come commercial bullet breaker resolution




It seems like the user is discussing a situation with a DC circuit breaker that has a burned contact on one side and they've identified a solution. Here's a clearer interpretation of their message:

"I discovered that a crimped-on wire ferrule solved the issue. I am pursuing a commercial circuit breaker solution."

This means they found that properly attaching a wire ferrule (a metal band used to consolidate stranded wire to ensure a reliable connection) resolved a problem, likely related to the burned contact. Now, they are looking into a professional or commercial-grade circuit breaker as a more permanent solution.