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Discussion Starter · #1 ·
Hi guys I have just bought this 1500w pure sine wave . After my novapal 1000w just decided to stop working but it keeps tripping . Also on occasion trips the 100a fuse under the bonnet . I have used a 1200w circular saw , 600w induction hob , 1000w hoover and it’s the same . How do I post a video on here . Can anybody help please because I have no idea
 

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A little more info might help. Just what is the Inverter working off? The 12v sub system or the HV battery and in which EV? Are you sure this shouldn't be in the power fuel alt energy forum.

1200 Watts at the usage point would be 1260 to 1320 watts into the Inverter as you have to allow 5 to 10 % losses possibly more on a bad design. Motors though can have a startup draw which may causing tripping. A 600 watt induction hob sounds low power. Our portable one is 3kW peak though when running can be just a few hundred or less when keeping warm.
 

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I suspect you are seeing the effects of voltage sagging under load and your inverter is tripping out due to under voltage. Most 12v inverters have a low voltage cut off at 11.5v so you can 'hopefully' still start the engine after using the inverter. All of the devices you mention have high inrush currents on start up you need to look at your inverter to see what it can support. Pulling over 100A from the battery will cause it's voltage to drop. you could put a 2nd battey in parallel to bost your current capacity.
 

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Discussion Starter · #4 ·
Sorry yes I have a video of the system, it’s in a kangoo ze . The inverter is wired to the 12v battery . I have the ignition on when using so the dc dc is charging it also . I have a 100w solar wired too .
Rectangle Automotive exterior Bumper Audio equipment Cable

Gadget Audio equipment Measuring instrument Gas Rectangle
 

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Discussion Starter · #5 ·
I suspect you are seeing the effects of voltage sagging under load and your inverter is tripping out due to under voltage. Most 12v inverters have a low voltage cut off at 11.5v so you can 'hopefully' still start the engine after using the inverter. All of the devices you mention have high inrush currents on start up you need to look at your inverter to see what it can support. Pulling over 100A from the battery will cause it's voltage to drop. you could put a 2nd battey in parallel to bost your current capacity.
Thanks for your reply , I have the van turned on so the dc dc charges the battery . Strange how the 100a has tripped on a 1200w saw and the hoover runs for about 30 seconds and then stops and starts again and the process keeps doing this . At a loss really and I need to able to rely on the power
 

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1500 W, at a nominal 12 VDC = 125 A. .

The inverter will almost certainly draw more than 125 A from the supply, too. At best it might be around 85% to 90% efficient, so although the the 1200 W load from the saw is going to be a DC current of around 110 A from the 12 V supply, only slightly over the 100 A maximum, there will most probably be a starting current that may be two or three times the running current in all probability. Wouldn't surprise me if the thing drew 250 to 300 A for a short time at the start up of a hefty load.
 

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100a at 12v is 1200w but the Inverter will draw more due to losses . And a 1500w Inverter could draw 1500/12 amps or 125 amps not a sensible choice.

With 60 to100 plus amps in the 12v wiring even the slightest poor connection in the wiring will drop the voltage. For example 1/100 of an ohm in a connection will loose 1 volt at 100 amps and get hot but also drops the input to the Inverter to 11v so it needs to draw extra current to keep the voltage up.

These amperages are on par with Rapid chargers and you've seen the cables they use.

A small petrol jenny would seem more sensible at these power levels.
 
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FWIW, the cable size to safely carry 100 A would be 25mm², for 125 A this really needs to go up to 35mm². 25mm² low voltage cable is around 9mm to 10mm in diameter, so pretty hefty.
 

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Discussion Starter · #10 ·
I think I told you back in October what to use rather than the inverter, didn't I?
Yes you did and I spoke to the guys at sunshine solar and explained my installation and this is what they recommended even though I mentioned my reservations about the setup ( as you said ) they said they wouldn’t recommend a battery generator. The only thing I can see that is capable is the Festool power station but at £2500 is ridiculous. I can’t believe it’s trips using the vango sizzle induction hob though .
 

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Yes you did and I spoke to the guys at sunshine solar and explained my installation and this is what they recommended even though I mentioned my reservations about the setup ( as you said ) they said they wouldn’t recommend a battery generator. The only thing I can see that is capable is the Festool power station but at £2500 is ridiculous. I can’t believe it’s trips using the vango sizzle induction hob though .
Can you let us know what size cables you used to wire this up? I suspect, as others have said, that there may well be an issue with the voltage drop.
 

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Thanks for your reply , I have the van turned on so the dc dc charges the battery . Strange how the 100a has tripped on a 1200w saw and the hoover runs for about 30 seconds and then stops and starts again and the process keeps doing this . At a loss really and I need to able to rely on the power
You are seeing exactly the effect I described the hoover pulls down the battery voltage below the inverter shutdown value and it shuts off, when the load is removed the voltage recovers and it restarts.

Your DC - DC converter in the van was not designed to push high currents into a battery doing what your doing risks damaging the converter.

I'm assuming all of this worked before you replaced the inverter?
Did you buy a low cost inverter?

If it's yes to both then I suggest you replace your inverter like for like or use a different one, I've done several of these DC to AC power projects using 'Victron' inverters and never had a problem.
I have no connection with Victron.
 

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Discussion Starter · #13 ·
You are seeing exactly the effect I described the hoover pulls down the battery voltage below the inverter shutdown value and it shuts off, when the load is removed the voltage recovers and it restarts.

Your DC - DC converter in the van was not designed to push high currents into a battery doing what your doing risks damaging the converter.

I'm assuming all of this worked before you replaced the inverter?
Did you buy a low cost inverter?

If it's yes to both then I suggest you replace your inverter like for like or use a different one, I've done several of these DC to AC power projects using 'Victron' inverters and never had a problem.
I have no connection with Victron.
Thanks for your response, it’s from sunshine solar ( a reputable company?) I paid £250 for the inverter.
 

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Discussion Starter · #14 ·
Can you let us know what size cables you used to wire this up? I suspect, as others have said, that there may well be an issue with the voltage drop.
I have used 16mm cable from the battery to the inverter ( the inverter comes with 2 positive and 2 negative 8mm cables so I have used a junction box to connect the 2 from the inverter to the single 16mm . The 16mm cable has an 100a breaker on it next to the 12v battery . I used this when I had the 1000w novapal inverter and it was ok until something went pop and blew all 3 40a fuses ( I only turned the inverter on when this happened with no load ) I replaced the fuses and just displays a continuous fault beep . That’s why I bought this new one not from Amazon
 

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3000 W surge power from a 12 VDC supply is a whopping 250 A. I very much doubt that any standard car battery is going to be able to handle that without a hefty voltage drop, and the cabling needed to handle it is going to be massive.

The bottom line is that this is asking way too much from what is a pretty low power DC source.
 

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The original ze battery is 74ah really not suitable to drive a 1500watt Inverter. This Inverter is designed for an ice car with a massive alternator and battery. Not for an ev with tiny battery and dc/dc converter.
Just to keep voltage loss down you need a chunky cable from the battery to the Inverter and the return should be direct via a similar one not via the chassis, any resistance will stuff this at the amperage your trying to pull.
 
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