Water Sparkplug

[revizal]

Vexus on SUV (video explaination)

All,

YouTube - Vexus on SUV (explaination)

I've make a video to explain the Vexus setup on my SUV.
I prefer to use 100 watt bulb to home plug or UPS while riding riding instead of inverter. Later it should find better way to restrict 0.5 A current to the circuit.

Rev.

[jstadwater]

Hey Greg and everyone,

Like Jetijs once told me, Welcome to the fried inverter club! I guess letting the smoke out of at least one inverter is the price for joining the club, as xpskid mentioned. An observation, I was not able to much more than turn on the inverter and immediately smoke one before I used the isolation transformer in-line on the AC side. Just a thought, is there a 12-14VDC isolation transformer we can use between the battery and inverter? Maybe that would serve to "finish" the isolation process and give us what we're looking for. What are the thoughts of all about this? Later.................Mike

[Jetijs]

Mike, transformers do not work on DC.

[jstadwater]

OK,

So, any device that can be used to "absorb" the spike that could be placed between the battery and inverter? The isolation transformer already takes care of the AC side right? There has to be something that would work here.


Mike

[Jetijs]

maybe we can somehow use transil diodes like the 1.5KE15A, these are designed to absorb high voltage spikes and can handle very powerful pulses. I use these for my attraction motor instead of a neon bulb and they work very fine. They have a peak pulse power of 1500W. Thanks to lighty for this idea.
Here is a datasheet:
http://www.argus.lv/pub/datasheets/1_5KE_C_CA.pdf
Maybe we can put these diodes in parallel to the 12V input and they will start to conduct only if voltage becomes greater than 15V and discharge that spike to the ground. I am no expert so maybe someone can show us how to use these correctly.

[Jetijs]

I mean something like this.



In theory that diode should ground all the voltages that get above 15V, leaving the inverter unharmed.

[gmeast]

Tvs

I mean something like this.



In theory that diode should ground all the voltages that get above 15V, leaving the inverter unharmed.

Hi Jetijs,

Yes a TVS (transient voltage suppressor) located where you indicated should work. I would use a bi-directional TVS ... suggested by Chris31 from OverUnity.com.

Thanks for input,

Greg

[jstadwater]

Cool, I wonder if the local Radio Shack would carry that diode, probably have to order it though. That just might work. Was I correct to assume that while using the isolation transformer, that side (AC side) is already completely protected? So, the only other thing to contend with is the battery side of the inverter.

Thanks....................................Mike

[gmeast]

Tvs

Hi Jetijs,

Thanks for input,

Greg

[gmeast]

Tvs

I mean something like this.



In theory that diode should ground all the voltages that get above 15V, leaving the inverter unharmed.

Hi Jetijs,

Yes a TVS (transient voltage suppressor) located where you indicated should work. I would use a bi-directional TVS ... suggested by Chris31 from OverUnity.com.

Thanks for input,

Greg

http://home.pacbell.net/gmeast/VW/typtvsap.pdf

[Chris31]

In theory that diode should ground all the voltages that get above 15V, leaving the inverter unharmed.

Jetijs, no harm in putting a TVS across the inverter input. But its the spikes from the ignition coil that are getting into the inverter output stage and destroying it. Put a bi TVS across the output of the inverter. On a DC put a unidirectional TVS, on AC like the inverters output put a bidirectional TVS across it.

There have been mention of caps getting hot? this is most likely from a negative or over voltage getting into the capacitor.

Make sure you use the TVS with the correct breakdown voltage.

I would use a bi-directional TVS ... suggested by Chris31 from OverUnity.com

Im also in this forum lurking

[Jetijs]

Thanks Chris
In that case the circuit should look like this:


The 12v side diode is rated for 15V and the inverter output size diode is rated for 150V. Of course those who are working with 230V inverters should use diodes with greater breakdown voltages on the AC side. And of course the diodes should better be bidirectional. For example the 1.5KE150A is a unidirectional diode, but 1.5KE150CA is a bidirectional one, so look for those who have a "C" in the name When you have installed them, you should also check their temperatures. If they get too hot, then maybe you need more of them in parallel or just attach a heatsink to the diode. Also to be absolutely sure, you ans put another 1.5KE150CA diode on the other side of the isolation transformer
Thanks,
Jetijs

[Chris31]

Jetijs

The TVS across the input of the inverter should be a unidirectional. You dont want any negative spikes getting though.

A bidirectional 15V TVS would allow +15V and -15V through.

[Jetijs]

Yes, you are right. My mistake.
Here is the corrected circuit:

[jstadwater]

Just ordered the diodes, 2nd day delivery. I hope this works for us, now the bad part...........waiting for them to arrive so I can install into the circuit! Thanks guys, for such a quick response with a possible solution for our inverter issues. You guys are the best!!

Later.......................... Mike