Change generator output from AC to DC and use PV in inverter as backup solution - good solution to use generator in your system.

[Bossman253]

Well i have generator without Inverter so it has poor AC quality. As many of you perheaps, so i dont want to connect it to Inverter as it could do harm to it.

I was thinking about chargeverter but since connecting chargeverter could make problems in terms of false battery reading in inverter.

I have idea to straighten AC to DC with this

and connect diode in PV Connection to separate string 1 from 2 and connect gen DC to second string PV in Inverter

What do you think is it safe and realiable solution, i think it could eliminate chargeverter solution and much much lower the cost.

 

[Crowz]

Well i have generator without Inverter so it has poor AC quality. As many of you perheaps, so i dont want to connect it to Inverter as it could do harm to it.

I was thinking about chargeverter but since connecting chargeverter could make problems in terms of false battery reading in inverter.

I have idea to straighten AC to DC with this
View attachment 243914
and connect diode in PV Connection to separate string 1 from 2 and connect gen DC to second string PV in Inverter

What do you think is it safe and realiable solution, i think it could eliminate chargeverter solution and much much lower the cost.

How would a chargeverter be any different than what you are talking about doing?

Its a battery charger that works with dirty power from a generator. It would be no more of a false battery reading than using any other dc source charging/providing dc power.

 

[Bossman253]

Chargers Itself it would be same as you state, but importance is there that Inverter has it on PV, and not bypassing Inverter and connected to battery. So statistics are without any false reading. It is always better to pass thru Inverter everything since it is heart of the system, not bypass it.

Correct me if i am wrong?

 

[Bossman253]

It would be no more of a false battery reading than using any other dc source charging/providing dc power.

That is not true

 

[Crowz]

generator (ac) > inverter with batteries > house power

generator (ac) > chargerverter > batteries (inverter drawing from batteries) > house power

Where is the difference?

You can set the chargeverter voltage to where you want the batteries to stay charged at and as the inverter draws from it the chargeverter ramps up to make up the difference in power.

So 52.0v battery setting > inverter draws 10 amps needed to run house load > chargeverter puts out 10 amps needed by inverter so battery stays at 52.0v.

I may not be understanding what your wanting. Sorry if this doesn't help.

 

[timselectric]

Yeah, I don't get it, either.
What's a "false battery reading" ?
The inverter doesn't care what the source is, as long as it provides what it wants.

 

[Offgrid Jungle]

He is asking if he can connect his generator directly to a MPPT input on his inverter, after running his gen output thru a rectifier bridge.

Let’s say it is ok and set aside the technical pitfalls. You will have a generator running unloaded once you battery s charged wasting fuel. You’re better off buying a new generator.

 

[Crowz]

He is asking if he can connect his generator directly to a MPPT input on his inverter, after running his gen output thru a rectifier bridge.

Let’s say it is ok and set aside the technical pitfalls. You will have a generator running unloaded once you battery s charged wasting fuel. You’re better off buying a new generator.

Or a chargeverter

 

[marionw]

Generator AC output to DC using a full wave bridge rectifier will indeed produce DC but the DC output because it is not filtered with inductors and capacitors will have a sawtooth like output, not a smooth DC/Constant voltage output. If you were able to filter the DC output and get it stable then maybe (I say maybe) you could use that as an input to the MPPT rather than a string of PV Panels.

Not sure about the efficiency (or safety).

 

[Bossman253]

Well if i have BMS connected to Inverter by CAN, it reads volts from battery, it have all readings from BMS and provide charging acordingly to BMS status. If i put chargeverter after BMS - does that produce any implications for inverter communication with bms or for inverter itself, additional power from chargeverter goes to inverter battery socket.

 

[marionw]

Normally the Chargeinverter is off except when you need to charge the batteries for whatever reason, low PV Array output for example. As the Chargeinverter charges the batteries assuming the Inverter is charging the batteries as well and not drawing power form the batteries, the BMS will report to the Inverter the current battery data based on the battery being charged from two sources. If the Inverter is drawing power from the batteries, the Chargeinverter, depending on it's settings will charge the battery AND provide power into the inverter or if it's programmed output voltage is less than the battery, will sit idle and provide no power until the battery voltage is less than the Chargeinverter's programmed voltage settings.

Many folks use two or more MPPT Charge Controllers (SCC) separate from their inverter, in many cases to handle larger PV arrays. These extra SCC will act very similar to the Chargeinverter. They will charge the battery and/or provide power to the Inverter.

 

[Bossman253]

Normally the Chargeinverter is off except when you need to charge the batteries for whatever reason, low PV Array output for example. As the Chargeinverter charges the batteries assuming the Inverter is charging the batteries as well and not drawing power form the batteries, the BMS will report to the Inverter the current battery data based on the battery being charged from two sources. If the Inverter is drawing power from the batteries, the Chargeinverter, depending on it's settings will charge the battery AND provide power into the inverter or if it's programmed output voltage is less than the battery, will sit idle and provide no power until the battery voltage is less than the Chargeinverter's programmed voltage settings.

Many folks use two or more MPPT Charge Controllers (SCC) separate from their inverter, in many cases to handle larger PV arrays. These extra SCC will act very similar to the Chargeinverter. They will charge the battery and/or provide power to the Inverter.

Thank you for answering me. It is more clear now for me. So basicaly it has to be properly setup on chargeverter and inverter. There is no implications for Inverter to receive charging power from chargeverter and battery (bms will pass thru what batteries need, and inverter will do the same).

Right ?

Is there a place i could start to setup proper chargeverter settings along with Deye inverter. Thanks in advance.

So my idea to make it thru Solar port isnt good choice ?

 

[wpns]

Thank you for answering me. It is more clear now for me. So basicaly it has to be properly setup on chargeverter and inverter. There is no implications for Inverter to receive charging power from chargeverter and battery (bms will pass thru what batteries need, and inverter will do the same).

Right ?

Is there a place i could start to setup proper chargeverter settings along with Deye inverter. Thanks in advance.

So my idea to make it thru Solar port isnt good choice ?

So there are two discussions going on here:

1) Is it OK, or safe, or a good idea, to make DC from a generator using a bridge rectifier (and appropriate capacitor) and feed that DC voltage into a SCC MPPT input? The answer is: It depends on the input characteristics of the SCC input, and no-one but the inverter manufacturer knows for sure. Solar panels are current-limited voltage sources, and if the SCC input draws too much current (I'm looking at you Victron, and any PWM-style input) you may let the magic smoke escape.

2) Can I connect a ChargeVerter directly to my batteries and charge them independently of my other charge sources (SCC, etc)? The answer is: Yes. Connect the CV to your 48V battery bus and plug it into your generator as required. There are a lot of optimizations around CVGC and other controls, but essentially it's just another battery charger, as others have mentioned. If running it manually I'd set it to the maximum charge voltage (bulk?) of your batteries and shut your generator down when the current starts to taper off to maximize charge efficiency.

 

[TM48]

You should be able to source a 48V battery charger where you are maybe even the Chargeverter under a different badge. I don'y know who actually manufactures it; someone here may know.

 

[DIYrich]

"False reading" is an issue when inverter controls battery charging based on battery voltage, and not comms. The inverter sees 50v and turns on the generator. The chargeverter puts charge voltage on the battery connection (say 55v), and the inverter gets confused. The inverter isn't supplying the charge voltage so doesn't know what happened.

CV2 where the CV2 controls the generator solves that problem.

 

[Bossman253]

"False reading" is an issue when inverter controls battery charging based on battery voltage, and not comms. The inverter sees 50v and turns on the generator. The chargeverter puts charge voltage on the battery connection (say 55v), and the inverter gets confused. The inverter isn't supplying the charge voltage so doesn't know what happened.

CV2 where the CV2 controls the generator solves that problem.

So if i wire inverter and get readings from battery not from bms by comms, there will be a problem ?.

What is CV2 ?

 

[Rednecktek]

Generator AC output to DC using a full wave bridge rectifier will indeed produce DC but the DC output because it is not filtered with inductors and capacitors will have a sawtooth like output, not a smooth DC/Constant voltage output. If you were able to filter the DC output and get it stable then maybe (I say maybe) you could use that as an input to the MPPT rather than a string of PV Panels.

Not sure about the efficiency (or safety).

Ya know, that sounds like a pretty cheap solution to the charging issue folks have with small 120v generators and 240v inverters. Rather than dropping hundreds of dollars on a 240v generator or a chargeverter that can only use 1/2 or less of it's capabilities, a rectifier, a big oll' capacitor, and an old computer heat sink should do the trick, right?

 

[Bop]

Many folks use two or more MPPT Charge Controllers (SCC) separate from their inverter, in many cases to handle larger PV arrays. These extra SCC will act very similar to the Chargeinverter. They will charge the battery and/or provide power to the Inverter.

In my own case, I'll be running 4x 60A external MPPT charge controllers, plus the two internal ones in the inverter, to handle the full 18kw on the house... (3 separate arrays facing in three different directions - N, E and W, 6kw in each direction...)

They don't even have to be the same type, size or brand as some mistakenly think (indeed one system I worked on before I retired had 7 different charge controllers!!!), some PWM, some MPPT, fed from 3 different power sources (some were on wind gennies, some on solar (of varying ages and types of controllers) and a microhydro from Rainbow Power Company thrown into the mix as well lol (I used to work there part time decades ago lol, was fun seeing the old gear from my younger days, still in use a few decades later!!!)

 

[Bossman253]

That is why i have created this post, i have people in Poland that have made such solution already. I can send you pictures

 

[Bossman253]

Ya know, that sounds like a pretty cheap solution to the charging issue folks have with small 120v generators and 240v inverters. Rather than dropping hundreds of dollars on a 240v generator or a chargeverter that can only use 1/2 or less of it's capabilities, a rectifier, a big oll' capacitor, and an old computer heat sink should do the trick, right?

That is why i have created this post, i have people in Poland that have made such solution already. I can send you pictures

 

[Bop]

Several issues- firstly if using it as a 'step up' to get 240v US style from a small 120v generator- one, you still only get the same wattage (bit lesss actually) so if your genny is a 120v, 16A one, you will get less than 8A at 240v...

Two- you are feeding 'dirty' DC from a 'constant voltage source' into the MPPT controller, and you may find the inverter doing strange things (and the genny too) as it tries to make the generator behave like a constant current source like a panel...

Three- depending on your particular inverter- the genny 'dc' voltage may be too low (it won't work), or 'just right' (it may/may not work) or too high (it won't work, and neither will the inverter any more as the smoke escapes)

I would be VERY leary of doing this to any 'random old inverter'- the odds are against it working (especially longterm) and you risk blowing the inverters MPPT charge controller up...

 

[DIYrich]

What is CV2 ?

version 2 of the chargeverter that has some smarts added.

 

[Rednecktek]

That is why i have created this post, i have people in Poland that have made such solution already. I can send you pictures

Yes please. Are they feeding it into a MPPT to their battery bank?

 

[DIYrich]

Two problems I see are:
1) MPPT will try to draw as much watts as it can by varying the voltage. Ignoring AC issues, that can overload the generator. You have to have a genny with an output greater than the mppt.

2) split phase 240v genny may be a problem. Because of neutral, you may need to put each line into a separate mppt. Now you have 60v on average on each line. Most AIO need about 100+ min voltage. 120v genny would be the same problem. Let's say you clip the 100-120v range, is that bad for the genny?

 

[DIYrich]

So if i wire inverter and get readings from battery not from bms by comms, there will be a problem ?.

What reading?