Faulty 24v 5000watt 110/240VAC split phase power jack inverter

Fabian

I have a 24v 5000watt split phase 110/240V power jack inverter.

I notice that whenever it is turn on and you are drawing load and the battery is charging. Once the battery reaches about 26.5V or sometimes around 27V it starts to beep and after several seconds it cuts off the output but it is still on but no output. 

During the beeping stage the output voltage is fine until it auto cutoff the output. You have to turn it off and turn it on back to get it back to work normal. If the inverter is on and no load is been drawn and the voltage keeps on rising up it does not cutoff the output until it passes 30vdc which is normal for most 24v inverter. So I am wondering if is the load on the inverter causing the premature alarm.

I saw on the net where i see the specs for it and it shows that the high voltage alarm is 27V. So is that the max input voltage it can handle? because if that is the case that  is very low as most 24v inverters go up to 30vdc max. I am wondering if the specs is accurate that I saw as it was for the 6000watt version.

The thing that puzzle me is that if it starts to beep around 26.5V or even little higher and you turn it off and turn it on back or you wait till the output auto cutoff it will continue to work little longer even thou the voltage rise pass the voltage it cutoff the last time. So basically if the battery is at 28v for eg. and you turn on the inverter it will continue to work until after awhile it starts to beep and then the output is cutoff. It appears to me that there is no set high voltage cutoff level.

I am wondering if the issue is been cause from the rising of the battery voltage under load or without load or it is cause from high temperature during the 26.5v stage or higher and because maybe when it reaches this voltage level and load is been pulled the fan does not chip in same time hence it cause the alarm to comes on and then the output is cutoff after several seconds as pass.

I can't figure out the root of the problem?

Can someone help me in this regards please? changing the control board would resolve my issue?

Running the fan continuous would resolve it if its a temperature issue?

Also is the fan that come in this inverter a 12v or 24v type? 

mcgivor

What sort of load is connected, motor, microwave, wattage  etc. , is there an indication that it is in fact an over voltage issue?  

BB.

Check the dc input voltage to the inverter. Sounds a little like cable or bad electrical connection. You have high DC current draw at the inverter input, and the bus voltage falls to 21 volts or less,  causing a low input voltage fault. Even if the battery voltage itself is ok.

-Bill

Fabian

how do i go about disabling/removing/adjusting the overvoltage protection on the control board? Where exactly on the board i would find that section or which chip would deal with that?

I am guessing if that section is disable i could be able to use the inverter with a voltage rising up to about 29v?

mcgivor

The purpose of the overvoltage protection is to protect the internal components, disabling protection would subject the circuitry to voltage greater than design parameters, which could lead to premature failure. The limit on voltage is dependent on the intended use of the inverter, it would seem obvious the Power Jack is not intended for a solar installation, where voltages are often higher than the cut out threshold. Opinions, for what they're worth.

Fabian

i would still want to know how to adjust the settings just to do some experiments.

Estragon

I don't know anything about that particular inverter, but if I made it I'd likely set the HVCO in NVRAM.

Fabian

Recently the inverter stop working. I heard a loud bang sound from it and immediately there was no output. When i open it i discovered about 8 fets got damage. I change all of the fets a total of 24.

I turn it on after the repair and it came on but with no output. On the LCD shows that it is drawing about 550watt which currently I do not have any load on it and it shows about 27vac output.

When  i test the output with my multimeter I don't get reading. I am wondering if something got damage on the control board as well or maybe the transformer got damage?

At the time when the loud bang occur i was drawing just some small loads just about 200watt and there wasn't any form of short circuit or overload in the house so i am kinda confused as to how the fets got damage.

Could it be the that the control board is giving problems as well or is it that the transformer got damage?

I examine the transformer and i don't see any form of damage I only notice that it has 5 wires coming from it. 2 heavy gauge wires and 3 smaller gauge wires and when you test them with the multimeter I get open/continuous reading on all of them. The transformer is a toroid design, is this a normal reading for it?

bill von novak

Fabian said:

Recently the inverter stop working. I heard a loud bang sound from it and immediately there was no output. When i open it i discovered about 8 fets got damage. I change all of the fets a total of 24.

I turn it on after the repair and it came on but with no output. On the LCD shows that it is drawing about 550watt which currently I do not have any load on it and it shows about 27vac output.

When  i test the output with my multimeter I don't get reading. . . .

I examine the transformer and i don't see any form of damage I only notice that it has 5 wires coming from it. 2 heavy gauge wires and 3 smaller gauge wires and when you test them with the multimeter I get open/continuous reading on all of them. The transformer is a toroid design, is this a normal reading for it?

If you are getting "no readings" from anywhere in the inverter and all the transformer turns are open . . . I'd suspect your meter first.   A transformer failing so that ALL its windings are open is very, very unlikely.

Fabian

so base upon the issue what would be the root of the problem? the control board? because there aren't any ICs on the fet board just some fets, caps and resistors. So i don't think it is that board still giving issues after I change the entire fet setup.
if the transformer was damage there would be evidence right? because it looks quite normal to me. there are no rip or burn smell or burn mark and no evidence of insulation strip looking on it from the outside view.
The loud sound that i heard would be from the fets when they pop rite? and in that case the current would be cut so no damage would begin to occurred to the transformer?

mcgivor

Were the transformer readings taken with the transformer mounted on the circuit board or removed, if mounted the readings would be inaccurate.

Fabian

The transformer was removed.

mike95490

Capacitors will pop with a bang.  FET's not so much, other than the plastic heating up and flaking off.  They'd have to get real hot, real quick to vaporize parts fast enough to make a loud bang

Vic

When FETs are blown,  it is fairly common for the FET Drivers to also be damaged.

With a serious short,  internal or external to the inverter,   it IS possible for the FETs to have part of the cases blown off.   This can happen when there is a massive violation of the Safe Operation Area of many semiconductors,   including FETs.

If the bang noise was from a/come capacitors,   one would usually find capacitor guts scattered around inside the device (inverter).

IMO,   Good luck,   Vic

Fabian

So basically i can presume that the transformer is ok?  because as i said before I don't see any form of damage to it.

I don't see any drivers for the fets on their boards. All i see is some balancing resistors. I notice that the fets or on 4 different boards with 6 fets on each and each board is equip with a Led which lights up now on all 4 boards so is that a sign to show that the fets are operating perfectly on each of the boards?

Would the drivers be on the control board which is mounted on top of the fet boards? Or could the control board be at fault resulting in me getting no output? When I connect up the transformer to the mainboard and the control board and I test all of the transformer connections I get open/continuous readings and when I remove the transformer from the control board there is no open/continuous reading between the live and the neutral connections so I am kinda confused it appears to be the transformer at fault but I don't see any damage to it. Could there be an hidden damage which is not obvious?
I really hope the transformer is not at fault.

mike95490

ya know, this is not a battery operated radio you are mucking about in.  You either know what you are doing with high power electronics, or you do not.   I'm starting to worry for you.