diy solar

diy solar

Battery Bank Hard Stuck

1. Generator mode 120 to port 1 (29A receptacle).
2. AC input limit 27A.
3. DC charge current 70A. Which to my understanding is the most my Multiplus can deliver?
4. They were both disabled by default.
5. Started generator today with battery bank at 24.1V. The charging current is sitting at around 45A. So my charge is only about half of your said 100A.

1. Good!

2. Good!

3. I was using VC in demo mode, so I might have selected the wrong unit that was 120A capable. If you can't go above 70A, then that's the limit.

4. My Quattros were enabled by default. Make for some crappy power output as it was synchronizing to my crap generator output which was 60±2Hz. With PowerAssist and UPS mode disabled, it doesn't try and sync with the incoming AC power.

5. At 24.1V, your battery is at a very low state of charge. What did the Victron battery monitor say for SoC? 45A is only ~1000W. Count on ~8 hours to charge the battery.

New Q's:
  1. Can you take screencaps of all the setup screens in VC and paste them here? Want to make sure I didn't miss something.
  2. Using a voltmeter, what is the DC voltage measured at the Victron DC lugs?
  3. As quickly as you can and without change in load/charge, what is the DC voltage measured at the battery terminals?
  4. What voltage does the Victron battery monitor report at that time?
 
1. Good!

2. Good!

3. I was using VC in demo mode, so I might have selected the wrong unit that was 120A capable. If you can't go above 70A, then that's the limit.

4. My Quattros were enabled by default. Make for some crappy power output as it was synchronizing to my crap generator output which was 60±2Hz. With PowerAssist and UPS mode disabled, it doesn't try and sync with the incoming AC power.

5. At 24.1V, your battery is at a very low state of charge. What did the Victron battery monitor say for SoC? 45A is only ~1000W. Count on ~8 hours to charge the battery.

New Q's:
  1. Can you take screencaps of all the setup screens in VC and paste them here? Want to make sure I didn't miss something.
  2. Using a voltmeter, what is the DC voltage measured at the Victron DC lugs?
  3. As quickly as you can and without change in load/charge, what is the DC voltage measured at the battery terminals?
  4. What voltage does the Victron battery monitor report at that time?
4. Oh my, well glad you got that figured out.

5. It said 68% for state of charge, so I will be needing to recalibrate that.

1.
Victron Screen 1.png
Victron Screen 2.png
Victron Screen 3.png
Victron Screen 4.png
Victron Screen 4.1.png
Victron Screen 5.png
Victron Screen 5.1.png
Victron Screen 6.png
Victron Screen 6.1.png

2. Victron Lugs =26.6V

3. Battery Lugs = 26.5V

4. Battery Monitor = 26.56V
 
Under Grid, disable wide-input. I forgot this cuts peak current to about 80% of specified. You might get a little more out of it.

LOL... I just realized this was enabled for me. Based on AC input, I should be able to get 1740W from my generator, but I typically get 1400.

1400/1740 = 80%...

I just fixed one of my own problems... :p
 
I would expect VC settings would override any switch settings, but check:


page 11, check that switches ds3 and ds4 are both ON to allow 100%.
This was stated in the section with the DIP switch information:
Note: when WeakAC is on, the maximum charge current is reduced from 100% to approximately 80%.
Both DIP switches were off manually and I switched them on. No noticeable difference in incoming current.

So the max I could get is 80%. I've tried toggling WeakAC off and the input from the generator gets up to 2000W+ and then kicks down to 200W and climbs back up and kicks down again; over and over.
 
LOL... I just realized this was enabled for me. Based on AC input, I should be able to get 1740W from my generator, but I typically get 1400.

1400/1740 = 80%...

I just fixed one of my own problems... :p
Hah, right on, glad to hear! Do you have Grid tie-in on your system?
 
Hah, right on, glad to hear! Do you have Grid tie-in on your system?

No. Pure off-grid.
This was stated in the section with the DIP switch information:
Note: when WeakAC is on, the maximum charge current is reduced from 100% to approximately 80%.
Both DIP switches were off manually and I switched them on. No noticeable difference in incoming current.

So the max I could get is 80%. I've tried toggling WeakAC off and the input from the generator gets up to 2000W+ and then kicks down to 200W and climbs back up and kicks down again; over and over.

Well, 2000W is an improvement.

Get your VM and measure the AC INPUT voltage at the inverter terminals as the power varies. You should see a relatively steady 120V. If you see notable voltage variation, your generator is the problem and likely has a failed voltage regulator.

Also check the Hz of the same terminals. You should see 58-62Hz (ish). If not, your generator governor is probably not so hot, or its not level, or the carb needs some work, etc.

If the above two measurements don't give any clues, try limiting the AC input to 15A. That should get you about 1800W - thinking we can sneak up on 2000W and stop before it gets there - at least improving it over the 45A charge rate.

EDIT: Also, on charger, disable WEAK AC INPUT
 
No. Pure off-grid.


Well, 2000W is an improvement.

Get your VM and measure the AC INPUT voltage at the inverter terminals as the power varies. You should see a relatively steady 120V. If you see notable voltage variation, your generator is the problem and likely has a failed voltage regulator.

Also check the Hz of the same terminals. You should see 58-62Hz (ish). If not, your generator governor is probably not so hot, or its not level, or the carb needs some work, etc.

If the above two measurements don't give any clues, try limiting the AC input to 15A. That should get you about 1800W - thinking we can sneak up on 2000W and stop before it gets there - at least improving it over the 45A charge rate.

EDIT: Also, on charger, disable WEAK AC INPUT
AC INPUT voltage at inverter terminals are a steady 112.1V.

The Hz measure at a steady 60.5Hz.

Limited AC input to 15A and the only noticeable difference I saw was that it was charging at around 1250W, as opposed to the 1310W it was power at when the AC input was set to 29A.

When I disable WEAK AC INPUT, the generator charges up to 2000W and then trips and restarts and does the same thing over and over again.

EDIT: Trips the inverter***
 
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AC INPUT voltage at inverter terminals are a steady 112.1V.

The Hz measure at a steady 60.5Hz.

Limited AC input to 15A and the only noticeable difference I saw was that it was charging at around 1250W, as opposed to the 1310W it was power at when the AC input was set to 29A.

When I disable WEAK AC INPUT, the generator charges up to 2000W and then trips and restarts and does the same thing over and over again.

Is that with the current limit set to 15A?

I haven't mentioned it recently, but every time you adjust the AC input limit, you need to decrease the charger current to be under that power-wise.

Let's assume you can pull 30A. Set AC Input current limit to that.

In any situation where you're seeing the 2000W trip, note the charger current and set your charger current to 10% under that, then increase it incrementally until it trips, then back off.

I was concerned that 112V was a problem... then I looked at the last record of when I ran my cheapo Predator... Holy smokes...

1636246570194.png

120V under low/no load... 110-112V under load.
 
My recollection is that the unit needs to be power cycled to accept/apply the dip switch changes.

This may be a factor as well. Again, I think the VC settings are supposed to override the switches, but it can't hurt if we can't get it resolved.

Side note, cheap generators don't produce clean output:

1636247494128.png

You can see the inverter's output before the generator, then in UPS mode where it's synched to the generator, then generator off. UPS and PowerAssist should only be used if you want those functions and when you have a clean AC input.
 
This may be a factor as well. Again, I think the VC settings are supposed to override the switches, but it can't hurt if we can't get it resolved.

Side note, cheap generators don't produce clean output:

View attachment 71571

You can see the inverter's output before the generator, then in UPS mode where it's synched to the generator, then generator off. UPS and PowerAssist should only be used if you want those functions and when you have a clean AC input.
Yeah, I went ahead and followed @MisterSandals recommendation. No noticeable difference. It does seem like the software overrides the switches.
 
Is that with the current limit set to 15A?

I haven't mentioned it recently, but every time you adjust the AC input limit, you need to decrease the charger current to be under that power-wise.

Let's assume you can pull 30A. Set AC Input current limit to that.

In any situation where you're seeing the 2000W trip, note the charger current and set your charger current to 10% under that, then increase it incrementally until it trips, then back off.

I was concerned that 112V was a problem... then I looked at the last record of when I ran my cheapo Predator... Holy smokes...

View attachment 71570

120V under low/no load... 110-112V under load.
I turned off Weak AC Input and limited the charge current to 60A from 70A. And I am now drawing 1900W from the generator. The generator was running at a steady hum when Weak AC Input was selected. Now it varies in it's behavior (sound-wise).

Haha, yeah, I was curious about the 112V too.
 
Yeah, I went ahead and followed @MisterSandals recommendation. No noticeable difference. It does seem like the software overrides the switches.

Good. Thought so.

I thought I already mentioned it, but I didn't find a post on it, Dynamic Current Limit on General may need to be disabled. It's generally a good idea to keep the load from hitting too hard, but you might get better performance with it off.

I turned off Weak AC Input and limited the charge current to 60A from 70A. And I am now drawing 1900W from the generator. The generator was running at a steady hum when Weak AC Input was selected. Now it varies in it's behavior (sound-wise).

Haha, yeah, I was curious about the 112V too.

Well, that's better - getting a full charge down closer to 5 hours. I think you can tweak things incrementally from here and find the breaking point. Once you find it, take one step back from there. :)
 
Thanks for sticking with it and talking me further through the process. Wouldn't have gotten there without your aid and I am very appreciative!
 
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