Malfunctioning Giandel 2000W inverter?

[DPCabin]

When there is no solar power to my 600W panels at night and no electrical draw on the batteries (24V and 400 ampH), my Giandel inverter alone is reducing the voltage well below the 50% level for the batteries. When I turn the inverter off, the voltage returns to a reasonable level. In other words, the voltage with the inverter on might be 23V but jump back to 25.5V when I turn it off. This is a problem at night but not when power is coming in during the day. Could the problem be some component in the inverter malfunctioning? There are no setting and minimal instructions with the inverter as I recall because I wanted to set a low-voltage cutoff on it and I wasn't able to. I believe the factory default is 19V which is way too low. Any suggestions or ideas much appreciated. Thanks. Dot

 

[sunshine_eggo]

Inverters have an idle draw, but I wouldn't expect it to use more than maybe 20-30W continuous in addition to loads.

Something sounds amuck.

Worth checking that all your connections/crimps are good and tight. You may also be over-using your 600W PV. Are you certain you're getting fully charged every day?

 

[GLC]

When there is no solar power to my 600W panels at night and no electrical draw on the batteries (24V and 400 ampH), my Giandel inverter alone is reducing the voltage well below the 50% level for the batteries. When I turn the inverter off, the voltage returns to a reasonable level. In other words, the voltage with the inverter on might be 23V but jump back to 25.5V when I turn it off. This is a problem at night but not when power is coming in during the day. Could the problem be some component in the inverter malfunctioning? There are no setting and minimal instructions with the inverter as I recall because I wanted to set a low-voltage cutoff on it and I wasn't able to. I believe the factory default is 19V which is way too low. Any suggestions or ideas much appreciated. Thanks. Dot

I have 2 Giendel 4000 watt inverters, at idle they only pull 4 watts each with no load. If your 2000 watt is pulling that much power something is a little wacky. Do you have a shunt between your battery and inverter where you could read the actual draw with no load?

 

[DPCabin]

I have 2 Giendel 4000 watt inverters, at idle they only pull 4 watts each with no load. If your 2000 watt is pulling that much power something is a little wacky. Do you have a shunt between your battery and inverter where you could read the actual draw with no load?

Hi there! I'm a Texan too. Lived in Austin for 10 years in the 70s. Sadly, I don't have a shunt. I built this system for my cabin using Will's website info and didn't add a shunt. If I have unplugged the line from the inverter to my circuits then the only 2 things that could draw current are the inverter and a DC line that has a light on it. If I turn the inverter off and the voltage returns to a high value doesn't it implicate the inverter? The DC line has almost nothing on it and the fact that removing the draw on the inverter fixed the problem suggests the DC line isn't the problem, right? But, tell me what you were thinking the shunt would indicate. I'm struggling to figure this out obviously. I'd hate to buy a new inverter if if wasn't the problem.

On another related topic...as I just said, this may result in my buying a new inverter. I've wanted to expand my system anyway since I'm kind of maxing out this 2000W system. Are your 2 inverters in the same solar system? If so, do you have separate battery banks for each? I want to add some Li batteries, I have 4 sealed AGM batteries now, but my impression is that the battery banks need to operate as a unit their entire life. So, if I make a second battery bank, it would need it's own charge controller I presume, but can the two systems feed into one inverter? I guess I'm wondering why you have 2 inverters. I'm just beginning to think about expanding my system so obviously I need to do some research.

Thanks for taking the time to help me out.

 

[12VoltInstalls]

if I make a second battery bank, it would need it's own charge controller I presume, but can the two systems feed into one inverter?

If they feed one inverter, they are the same battery bank

How old are the batteries?

To measure the draw on the batteries from the inverter, a device such as this can be had for under $30 for constant monitoring. I would prefer this unit as it records sum kW and is inductive but the 100W range won’t work for you

Or one of these

 

[GLC]

Hi there! I'm a Texan too. Lived in Austin for 10 years in the 70s. Sadly, I don't have a shunt. I built this system for my cabin using Will's website info and didn't add a shunt. If I have unplugged the line from the inverter to my circuits then the only 2 things that could draw current are the inverter and a DC line that has a light on it. If I turn the inverter off and the voltage returns to a high value doesn't it implicate the inverter? The DC line has almost nothing on it and the fact that removing the draw on the inverter fixed the problem suggests the DC line isn't the problem, right? But, tell me what you were thinking the shunt would indicate. I'm struggling to figure this out obviously. I'd hate to buy a new inverter if if wasn't the problem.

On another related topic...as I just said, this may result in my buying a new inverter. I've wanted to expand my system anyway since I'm kind of maxing out this 2000W system. Are your 2 inverters in the same solar system? If so, do you have separate battery banks for each? I want to add some Li batteries, I have 4 sealed AGM batteries now, but my impression is that the battery banks need to operate as a unit their entire life. So, if I make a second battery bank, it would need it's own charge controller I presume, but can the two systems feed into one inverter? I guess I'm wondering why you have 2 inverters. I'm just beginning to think about expanding my system so obviously I need to do some research.

Thanks for taking the time to help me out.

First spend $21 for a monitor/shunt.

Amazon.com

You really need to know what the draw on your setup is, now and going forward. It will also let you know when you have everything on when your inverter is starting to max out by monitoring what is being pulled from your batteries as far as amp draw. It will also let you know when you need to increase your AH in your battery bank, meaning more battery's. Of course it is not the only thing that you consider but for sure you will see your load on your battery pack with inverter is on with a load and what the power drain with it off.

Are your 2 inverters in the same solar system? Yes

If so, do you have separate battery banks for each? No, both on the same bank of batteries. Previously i had two separate battery banks, separate controllers, separate panels. I combined everything.

I want to add some Li batteries, I have 4 sealed AGM batteries now, but my impression is that the battery banks need to operate as a unit their entire life. First, do not mix and match your batteries, LPO4-Flooded-AGM-etc, they all have different charging and life characteristics. Even mixing different age batteries from the same manufacturer can cause problems.

So, if I make a second battery bank, it would need it's own charge controller I presume, (Yes) but can the two systems feed into one inverter? When you connect your inverter using double cables to connect both battery banks, you will also be tying both battery banks together at the same time possibly creating charging and use issues like mentioned above.

I guess I'm wondering why you have 2 inverters? I started with two totally separate systems, panels, controllers, battery's, inverters, etc, to feed two separate manual transfer switches to power different circuits in my home. Then as my system grew, I purchase a 110/220 volt inverter to power my well pump which is 220. In doing this I just decided to combine everything since all of my LPO4 batteries were within a year of being new and all were the same brand. They all equalized well together. So I have a large bank of 12 , 100 AH batteries, wired 6p/2S making 24 volts. This powers appx 80% of my 110 needs for my house as longs as the sun is shining daily. Lights, wall plugs, TV's, microwave, washer, even a ductless hvac unit in our master bedroom when needed. Also with the second inverter,a 110/220 volt, it can power the well pump. Things i cannot power is whole house hvac, dryer and stove. I do have a regular electric 220 volt hot water heater but replaced the lower ac element with a dual probe 36 volt/2400 watt element. I power it by to strings of 3-305 watt solar panels hooked directly to each side of the heating element. My AC element rarely turns on as longs as the sun shines every day.

 

[DPCabin]

Inverters have an idle draw, but I wouldn't expect it to use more than maybe 20-30W continuous in addition to loads.

Something sounds amuck.

Worth checking that all your connections/crimps are good and tight. You may also be over-using your 600W PV. Are you certain you're getting fully charged every day?

No problem with panels. They fully charge batteries easily every day, even when shady. I'll check connections.

 

[DPCabin]

If they feed one inverter, they are the same battery bank

How old are the batteries?

To measure the draw on the batteries from the inverter, a device such as this can be had for under $30 for constant monitoring. I would prefer this unit as it records sum kW and is inductive but the 100W range won’t work for you

Or one of these View attachment 82189

Batteries are only 2 years old. The whole system is 2 years. I'll look into the tool you suggest. Thanks.

 

[12VoltInstalls]

Batteries are only 2 years old. The whole system is 2 years. I'll look into the tool you suggest. Thanks.

AGM batteries may only last a couple years if cycled daily, especially if cycled deeply.
If they were flooded but <15months I might suggest adding a few but two year AGMs I’m not thinking is a good plan.

If replacing them and LiFePo isn’t chosen I’d suggest maybe going with flooded batteries. 3-5 years on cheaper, more if treated well; maybe 5-10 years on good flooded batteries never cycled hard.

 

[DPCabin]

AGM batteries may only last a couple years if cycled daily, especially if cycled deeply.
If they were flooded but <15months I might suggest adding a few but two year AGMs I’m not thinking is a good plan.

If replacing them and LiFePo isn’t chosen I’d suggest maybe going with flooded batteries. 3-5 years on cheaper, more if treated well; maybe 5-10 years on good flooded batteries never cycled hard.

Thanks for you thoughts. The batteries have only cycled hard (below 50%) 2 times and for short periods of time. My understanding is that would not cause too much damage to them. I'm going to try turning the inverter off at night to see if they hold a charge better when it is not pulling on them. I am trying to determine if it is the batteries or the inverter that I should replace. I'll do Li batteries next time for sure. This has been a pain lately.

 

[DPCabin]

First spend $21 for a monitor/shunt.

Amazon.com

You really need to know what the draw on your setup is, now and going forward. It will also let you know when you have everything on when your inverter is starting to max out by monitoring what is being pulled from your batteries as far as amp draw. It will also let you know when you need to increase your AH in your battery bank, meaning more battery's. Of course it is not the only thing that you consider but for sure you will see your load on your battery pack with inverter is on with a load and what the power drain with it off.

Are your 2 inverters in the same solar system? Yes

If so, do you have separate battery banks for each? No, both on the same bank of batteries. Previously i had two separate battery banks, separate controllers, separate panels. I combined everything.

I want to add some Li batteries, I have 4 sealed AGM batteries now, but my impression is that the battery banks need to operate as a unit their entire life. First, do not mix and match your batteries, LPO4-Flooded-AGM-etc, they all have different charging and life characteristics. Even mixing different age batteries from the same manufacturer can cause problems.

So, if I make a second battery bank, it would need it's own charge controller I presume, (Yes) but can the two systems feed into one inverter? When you connect your inverter using double cables to connect both battery banks, you will also be tying both battery banks together at the same time possibly creating charging and use issues like mentioned above.

I guess I'm wondering why you have 2 inverters? I started with two totally separate systems, panels, controllers, battery's, inverters, etc, to feed two separate manual transfer switches to power different circuits in my home. Then as my system grew, I purchase a 110/220 volt inverter to power my well pump which is 220. In doing this I just decided to combine everything since all of my LPO4 batteries were within a year of being new and all were the same brand. They all equalized well together. So I have a large bank of 12 , 100 AH batteries, wired 6p/2S making 24 volts. This powers appx 80% of my 110 needs for my house as longs as the sun is shining daily. Lights, wall plugs, TV's, microwave, washer, even a ductless hvac unit in our master bedroom when needed. Also with the second inverter,a 110/220 volt, it can power the well pump. Things i cannot power is whole house hvac, dryer and stove. I do have a regular electric 220 volt hot water heater but replaced the lower ac element with a dual probe 36 volt/2400 watt element. I power it by to strings of 3-305 watt solar panels hooked directly to each side of the heating element. My AC element rarely turns on as longs as the sun shines every day.

Here's a photo of my setup. Would you mind telling precisely where to run the shunt? That would be so helpful if you have the time. Many thanks!

 

[12VoltInstalls]

I'll do Li batteries next time for sure. This has been a pain lately.

There’s also flooded batteries…
The pain is the discharging

Between switch and fuse I’d say

 

[GLC]

View attachment 82965
Here's a photo of my setup. Would you mind telling precisely where to run the shunt? That would be so helpful if you have the time. Many thanks!

Hi, it just need to be on the negative side between the battery and the inverter. Some connect it directly to the negative battery post and then connect a wire to the inverter. I have seen some connect it directly to the inverter, negative side and then run a cable to the negative on the battery. I have seen some put in somewhere in-between. I don't think it really matters a far as placement as long as it is on your negative battery side. What you are trying to accomplish is monitoring and tracking your watt draw out of your battery going to your inverter. If you also have a DC draw directly from the battery to a DC device, you would want another shunt there also on your negative cable feeding a separate fuse box feeding DC current load/loads. Looks like you already have a negative busbar on your setup. If you place your shunt before that busbar, that will work although it will register all watt draws out your battery's including you straight DC feeds to your appliances and inverter..