Need some troubleshooting help :)

[tazzalot]

Hi
I have a Renogy based setup in my van
BACKGROUND
2 off100ah batteries https://au.renogy.com/renogy-smart-lithium-iron-phosphate-battery-12-volt-100ah/
1 off 50 amp Dc to DC charger with MTTP
2 off solar panels
1 off 2000W 12V to 230V Pure Sine Wave Inverter (with UPS Function)
12volt LEDs etc etc

I'm trying to run a Nuwave induction cooktop

It is set up as per the attached pic

ISSUE
The cooktop is tripping out when running on 900 watts / low (drawing approx 850ish from the batteries) .. it will run for a few minutes then trip the whole setup ie lights cooktop invertor .. the whole deal
It will auto-reset within say 10 seconds and then away it goes .. then will trip again after a minute or 2.

THINGS I HAVE TRIED
Replaced the 1000-wat inverter for the 2000-watt inverter.
Upgraded leads from the battery to the inverter.

THOUGHTS
The 2000-watt inverter should be able to run a 900-watt cooktop ... the inverter fans aren't coming on so I'm assuming the invertor is capable of handling the load.

QUESTIONS
Why does the cooktop trip out the whole system
Do the batteries have some sort of overload protection which trips out

Happy to clarify / pics whatever .. this is driving me nuts

 

[rmaddy]

FYI - 4AWG wire is only going to work for a 1000W inverter on a 12V system. For a 2000W inverter you need 2/0AWG.

Show a picture of how your batteries are wired in parallel.

Are your batteries fully charged? What is their voltage when measure at the battery terminals?

Without the cooktop on, what voltage do you read at the inverter battery connections?
What voltage do you read at the inverter battery connections when the cooktop is on?

 

[tazzalot]

FYI - 4AWG wire is only going to work for a 1000W inverter on a 12V system. For a 2000W inverter you need 2/0AWG.

Show a picture of how your batteries are wired in parallel.

Are your batteries fully charged? What is their voltage when measure at the battery terminals?

Without the cooktop on, what voltage do you read at the inverter battery connections?
What voltage do you read at the inverter battery connections when the cooktop is on?

Thanks for your speedy reply .. much appreciated

Cable used


Battery connections


Individual battery voltages

1. 13.05volts
2. 13.04 volts

The voltage at the inverter .. no load 13.07 volts (?)

The voltage at the inverter under load 12.37 volts

Regards Stuart

 

[Rocketman]

You are not showing a battery monitor- like Victron Smartshunt. That is very important- so you know if your batteries are at 90% or 10%.

The No load voltage of 13.07 seems a bit low. Charge up the batteries to 100%.

Everything “should” handle the load - but it’s not so something is lying. My guess is the induction plate on low uses power then coasts then it uses power again at that one or 2 minute mark and it may be overloading the inverter by drawing too much power - it’s high/off/high/off not low all the time.

Do you have a clamp meter? A clamp meter and a Line splitter will tell you the amps that the induction plate are really using. (Look on Amazon for “line splitter for clamp meter”- I got the Klein unit).

The clamp meter is great to let you know how many amps are flowing in the wire (just make sure you get one that does both ac & dc. Having one that can show inrush current is very handy for problem solving like this - you could be getting an inrush at startup point too. (I am guessing- I don’t really know how induction plates work).

Good luck.

 

[Rocketman]

Also your battery wire looks like it is 2awg. That will handle about 100 amps. To get 200 amps (for the full power of the inverter - you need to get 2/0 wire or double-up the #2 wire.

As you start drawing more than 100 amps your voltage could be dropping which causes the inverter to hit its low voltage cut-off.

Good luck

 

[tazzalot]

You are not showing a battery monitor- like Victron Smartshunt. That is very important- so you know if your batteries are at 90% or 10%. .....

Good luck.

Thanks Rocketman

I have one of these fitted


And this is a terrible pic of what my is reading at the moment .. batteries are down because of multiple efforts to get the hot plate working



I'll pick up a clamp meter in the morning .. thanks again

 

[Bud Martin]

OP: "
ISSUE
The cooktop is tripping out when running on 900 watts / low (drawing approx 850ish from the batteries) .. it will run for a few minutes then trip the whole setup ie lights cooktop invertor .. the whole deal
It will auto-reset within say 10 seconds and then away it goes .. then will trip again after a minute or 2.

Please clarify as to which device has trip. The inverter?
Can we also see your whole setup?

 

[tazzalot]

Hi Bud
The whole setup goes down ... .. which has me leaning toward the batteries being the problem. I can't find any info on whether the Renogy batteries have some sort of inbuilt overload protection
I have house lights / USB chargers etc etc wired in and they all go done

These are the batteries https://au.renogy.com/renogy-12v-100ah-smart-lithium-iron-phosphate-battery-w-self-heating-function/

 

[mikefitz]

Try running a different load with the inverter at similar power levels, say a 1000 watt heat gun.
Also see is the issue is still present with engine running and thus additional power being added.

Test voltages at points in the circuit for excessive volt drops, it may be that the inverter is reaching low volts disconnect.

Assuming your inverter is a Renogy product, be aware that there have been reports of erratic operation and shutdown of these units, perhaps due to EMI. An Indiction cooktop could be generating lots of electrical noise and current pulsations.

If you have followed the connection setup in the first picture the interconnections are not ideal with multiple lugs on a single breaker stud.
Low cost breakers are unreliable and can introduce volt drops.

Cable length in the parallel connections of the batteries and the connection to the Inverter should be as short as practical.

Your batteries have over current BMS protection at just over 100 amps continious ( each battery) and low volts shutdown so beware this is a possibility.

Mike

 

[Zil]

Your battery has a BMS that is rated for maximum 100 amperes. Your inverter probably is pulling 150 + amperes.

 

[mikefitz]

There are two batteries in parallel, so a 200 amp capability, assuming both batteries are sharing.
It could be that they are not at the same state of charge and one is shutting down, followed by the other.
Voltage tests in the system may identify this.
It's advisable to fully charge each battery separately before connecting in parallel.
Mike

 

[Bobert]

It seems to me that your batteries are to low. Most lifepo4 batteries are less than %40 charged at 13.1 volts resting. If you have not been charging them to between 14 and 14.4 volts occasionally they will eventually become out of balance internally. Once they are out of balance your high voltage cutoff will become lower ( you won’t be able to charge to 14.4 without hitting high voltage cutoff) and low voltage cutoff will become higher ( the battery will cutoff power at a higher voltage than it is supposed to) this can result in the battery having substantially less charge at 13.07 volt s than is is supposed to have and simultaneously reducing the amperage load that you can place on the battery before low voltage cutoff is reached. Your batteries appear to be somewhat out of balance with each other also and that would multiply the problem if that is the case. As others have said it would be best to individually charge each battery till full to make sure that is not an issue.