Voltage but no amp readings on new set up. How do I trouble shoot this?

[showme]

I've had my system up and running (sort of) for months now, but I've got a problem i can't figure out. My panels (7,680w of LG 320w modules) are feeding the two Classic 150 charge controllers and 500ah of SOK LiFePo batts), are putting out their expected voltage and amps, per a complete check of individual panels the other day. For some reason the controllers are showing volts but not amps. I called Midnite Solar and they walked me through some troubleshooting steps, but no luck. So they had me send them back to them for testing, and they came back good. I've been told that there may be a short circuit or misconfiguration of the wiring. After I checked all the panels the other day with my Fluke 115 multimeter, I jumped down to the combiner box to check voltage and amps there, but when I touched the leads to the individual incoming series connections, the multimeter lead for the hot side would arc at every one of the connections. I;m running 3 panels in series, with four series parallelling in the combiner box. This arcing was at the input side of each breaker. And this happened at both arrays (two arrays with 12 panels each). I have the 4 series wires run in leak-tite 3/4" conduit from the top of the pole to the combiner. Anybody have any idea how to possibly troubleshoot this?

The inverters (Trace SW5548's) and charge controllers seem to be working fine, and the batteries are holding 53 to 56 volts, depending on the day, and are all staying withing 1- 1.5 volts of each other. This is an off grid system that will be our power after we build a house on the 43 acres there. Since the charge controllers have tested good, I'm now trying to find where the problem is hidden. Anybody had this problem, or have an idea of where to start looking? Thanks for any and all suggestions or ideas. Lee

 

[showme]

Sorry, that's 3/4" conduit. The edit button is only letting me edit the thread title.

 

[Prince Of Darkness]

The Arcing could, possibly, be caused by having the Fluke meter, set to Amps, and then trying to measure from the PV breaker terminal, to PV negative.

To measure current (Amps), the meter needs to be a DC Clamp meter, or the meter needs to be in series with the cicuit that you are trying to measure.

Good Luck, later, Luke

 

[Prince Of Darkness]

showme,

When you said, " For some reason the controllers are showing volts but not amps", What stage were the Classics in? Were they Resting?
If so, you could look up the Reason For Resting (RFR code).

EDIT :On the MidNite Forum there is the Knowledge Base, with a lot of detailed info about Classic troubleshooting, etc, here is the Topic for RFR:

MidNite Solar Help

customer support platform

www.midniteftp.com

<

Luke

 

[showme]

Thanks, Luke. By being in series, I'm guessing that you're saying that I should disconnect the wires coming into the combiner box and run the meter between the series + and - wires, meaning that by checking them still hooked up to the breaker and ground block was a mistake? I'm pretty sure that i even pulled the + line off one breaker, but may have just touched the - to the ground block. Per the resting state, they were showing no amps whether they were charging or not. After I got the Classics back from MS, it was kind of weird, but i got readings of very low amps (5-6??), but the last time I checked, I was getting 0 again. All the same, although i didn't put heavy loads on the inverters, everything i did run off of them did fine, and the batteries have not dropped as though they were being charged. It's almost like they are getting charged, but if the cc's aren't showing amps, how is this happeining? And, thanks, I will check out the RFR code as soon as i get back down to the property (30 miles away) where the system is set up.

 

[Prince Of Darkness]

Hi showme,

Will add, that, when there are several battery charge sources, (like your Wind Turbines), that the Classics might show PV input voltage, and no output current, especially when loads on the system are small. This often happens when other chargers are charging, or just maintaining Float voltage, have a target voltage setting that is a bit above the settings of the SCCs (like the Classics).

In the above case, the Classics display "Resting", or, in some cases, "Error".

It is quite possible that there is no problem with your system, at all.

Just a thought, FWIW. Good Luck, Luke

 

[bikerider4818]

Showme,
This last week I just went through the same thing. I knew my panels should be putting out around 4000 watts, but my app for my EG4 6500ex would show that it was only producing a max of 1000 watts at .5 amp and a max of 1 amp at short periods of time. I also saw that the inverter was only using one pv input and not much of the other pv input. Twice I went up and rechecked my solar wires and even replaced some of the mc4 plugs. My error was in a lack of knowledge about electricity, how to use my clamp meter correctly, and how the inverter uses the pv inputs. I just learned that amps is similar to measuring how much water is flowing through a hose. If you don't need much water, then your measurement of the quantity of water going through the hose will be low. Same with the pv wires and inverter. If you don't need much electricity, then your system will show low amps. Originally I started up my solar system by only connecting a couple of my home's circuits. I realized that the inverter only pulls enough amps and volts from the solar panels that it needs in order to supply enough power for the load on the circuits I had attached to the system. Over the last couple days, as I've added more circuits, my app shows higher and higher watts and amps. When I only had a couple circuits on my system, it showed that it was only using half of one amp but now that I've added more circuits, it now shows as using over 3 amps. I realized everything was working fine. The system just doesn't need the full 10 amps that my panels can produce. I don't know if you have the same situation, but it might be that your load is very low and your system just doesn't need to pull much from the solar panels. You might try plugging in something that pulls a lot of amps and see if your amp through your inverter goes up. I'm not an expert and I only know enough to be dangerous, but this is what I've observed. So far I haven't killed myself or burned my house down.

 

[showme]

Luke- the wind genny isn't up yet, so it's not a factor (yet), but thanks for bringing that up. I'll definitely take that into consideration when I do get the genny going. Yep, the classics have both run in resting and float, mostly. Between your reply and bikerider4828's reply, I'm starting to believe that by using the small (very small, actually) loads probably didn't even put a dent in the battery use, not to mention that it was daylight when i did run anything off of them. This may, I hope, be the answer, that I don't have a problem.

BR4828- I am almost jumping up and down after reading this. It never even occurred to me that the controllers may be showing nothing due to not needing to charge the batteries. As I mentioned above, it was daytime when i used a shop vac to clean the shed floor (less than 5 minutes), tested the fans I've installed to cool the shed, and one other power tool i used at the time for just a minute or so. And i checked the LED lights I've installed in the shed. Thank you very much for taking the time to reply and tell me about your experience. What kind of surprises me is that Midnite Solars' tech and Current Connections' tech weren't aware of this possibility! I've talked to both companies quite a few times about this problem. To be honest, I was starting to second guess running 4 pv wires through that 3/4" pvc seal-tite conduit, although I got quite a few replies on two forums that it should be fine. I was thinking I "over-filled" the conduit causing possible heat problems, or something. I also rant the (2) 6 awg wires and bare 10 awg ground wire through the same type of conduit from the combiner box, down the pole, then underground to the shed (about 35'). I started dreading the idea of having to dig up, pull wires or remove the conduit on two arrays to see if this was the problem. Anyway, your story at least gives me hope that all is well. But the tech at MS told me that I should be seeing close to what the total output of amps on the arrays on the controllers, not nothing or near nothing. But it almost sounds right, considering when i got the classics back from MS after they checked out ok that it was showing something like 5-6 amps on the classics, in that it may have been charging what was lost in the 2-3 weeks the controllers were at MS for testing. To be honest, I've had the system shut down for a month or so. I've misplaced some of the set up parameters for the classics, and I sure don't want to screw something up now. Thanks guys, this "might" be good news. I'll get down there and fire it back up and then report back. Lee

 

[bikerider4818]

Luke- the wind genny isn't up yet, so it's not a factor (yet), but thanks for bringing that up. I'll definitely take that into consideration when I do get the genny going. Yep, the classics have both run in resting and float, mostly. Between your reply and bikerider4828's reply, I'm starting to believe that by using the small (very small, actually) loads probably didn't even put a dent in the battery use, not to mention that it was daylight when i did run anything off of them. This may, I hope, be the answer, that I don't have a problem.

BR4828- I am almost jumping up and down after reading this. It never even occurred to me that the controllers may be showing nothing due to not needing to charge the batteries. As I mentioned above, it was daytime when i used a shop vac to clean the shed floor (less than 5 minutes), tested the fans I've installed to cool the shed, and one other power tool i used at the time for just a minute or so. And i checked the LED lights I've installed in the shed. Thank you very much for taking the time to reply and tell me about your experience. What kind of surprises me is that Midnite Solars' tech and Current Connections' tech weren't aware of this possibility! I've talked to both companies quite a few times about this problem. To be honest, I was starting to second guess running 4 pv wires through that 3/4" pvc seal-tite conduit, although I got quite a few replies on two forums that it should be fine. I was thinking I "over-filled" the conduit causing possible heat problems, or something. I also rant the (2) 6 awg wires and bare 10 awg ground wire through the same type of conduit from the combiner box, down the pole, then underground to the shed (about 35'). I started dreading the idea of having to dig up, pull wires or remove the conduit on two arrays to see if this was the problem. Anyway, your story at least gives me hope that all is well. But the tech at MS told me that I should be seeing close to what the total output of amps on the arrays on the controllers, not nothing or near nothing. But it almost sounds right, considering when i got the classics back from MS after they checked out ok that it was showing something like 5-6 amps on the classics, in that it may have been charging what was lost in the 2-3 weeks the controllers were at MS for testing. To be honest, I've had the system shut down for a month or so. I've misplaced some of the set up parameters for the classics, and I sure don't want to screw something up now. Thanks guys, this "might" be good news. I'll get down there and fire it back up and then report back. Lee

See my attached pictures. In the blue picture you can see that my load is currently only 602 watts and my inverter is only pulling 901 watts (inverter consumes some of the watts) from my solar panels even though I have about 4000-4500 watts of panels. In the second picture, PV1 shows 3 amps and PV2 only shows .7 amps. Earlier today I saw PV1 at 6 amps. I think my inverter prioritizes PV1. When I originally saw these numbers when I first turned my system on, like you I thought I had a problem because the amps did not match the amps shown on the label on the back of my panels which was 10 amps. But after checking every wire, undoing, redoing everything I realized my inverter is only showing what it needs to pull from the panels in order to supply enough electricity to the load. Again this is what I've observed and I could be totally wrong but I don't think so. But I have never really seen anybody on YouTube or online talk about this although I think will prowse as touched on it, but at the time I didn't quite catch on to what he was referring to.

 

[showme]

Thanks, BR, I really appreciate that update. I'm sorry to say that I haven't been able to get back down to the property and apply what i've learned on here yet. But I'm going to head down there tomorrow morning and I'll definitely see what i can find. Thanks again! Lee

 

[showme]

Ok, it's been awhile but after I got the two Airpax 80a PV breakers in and installed, things seem to have straightened themselves out. After reading one reply that said I should also consider that there was no load on it may have made this scenario a normal event. But now that I've fired it up with the new breakers, I'm reading the watts and amps on the slave, while it is normally in Float mode. The master is showing incoming and battery volts, (same with the slave), but usually no watts, since it's usually Resting, but amps show up sometimes. Anyway, the inverters are on 16w search sweep every 3 seconds since everything is pretty much idle while I'm not there, and usually when I am there, also. I'm still watching and learning. Since it's been down in the sub zero temps at night and single digits during the day, I bought a heater, just in case it dropped farther. The uninsulated shed has been at 20* (without a heater) every day when the temp outdoor temp was at 2-8*, depending on the day. I turned the 1500/750w infrared heater on for 30 minutes, it raised the temp to 35* and all went well, although one battery and the master cc acted a little weird after I turned it off. LEDs blinking "wrong", a 'tick...tock noise coming from the master classic, and an alarm light on one battery. But they were back to normal the next day. Anyway, I came across this unfinished post and thought I'd better update, since I was totally confused before the PV breakers (??) or whatever it was, brought it back to normal. I'm thinking bikerider4818 was right, and I was just ignorant enough to not understand what I was seeing. I was on Midnite Solar's forum asking for help on the master cc 'follow me' blinking LED that was going from fast to slow blink time, and a tick tock sound coming from the controller. bOB, the legend, told me how to get in the system to check and find out why it's resting, that the blinking is fine as long as it blinks fasts sometimes (this means the communication between the two controllers, or 'follow me' mode), and that the Reason for Resting may have to do with the ticking, but it shouldn't be there. As I said, the next day, everything was back to normal, so it "fixed itself", as did the battery. I'm happy, but this is still confusing. I wrote boB back and thanked him, but why in the world didn't MS include this information in their manual?? I read that manual from front to back and found nothing about Resting, except that it's a mode. Thanks for all the replies along the way, guys! If this changes, I'll report. Lee