On 2021/06/18 at 12:11 PM, 87 Dream said:

At least your battery is still in working order. So not all is lost.

Did you manage to check the fuses I mentioned earlier the 5 X 40A ones under the plastic shield material?

87

All four fuses look fine 

On 2021/07/07 at 2:55 PM, 87 Dream said:

Ok that rules that suspect out of the equation..any other noticeable burn marks or heat warped material now that you have gotten access under the plastic cover?

87

No I haven't. Looking from above and around everything is "pristine". No hints of scorching or anything else and can't smell anything burnt either.  

After learning a little about BMS I figure the BMS and the inverter charge circuit had a bun fight and the inverter lost

Running the same battery on the IVR1200 MPPT everything seems to work 100%, especially around the bulk charge cut off and not trickle charging the LiFEPO4

On 2021/07/16 at 12:45 PM, The_Scrutineer said:

No I haven't. Looking from above and around everything is "pristine". No hints of scorching or anything else and can't smell anything burnt either.  

After learning a little about BMS I figure the BMS and the inverter charge circuit had a bun fight and the inverter lost

Running the same battery on the IVR1200 MPPT everything seems to work 100%, especially around the bulk charge cut off and not trickle charging the LiFEPO4

How are you finding that IVR1200mppt? Do fans switch off when the battery is charged?

The ones I have here run continuously.

Does the mains side have a fuse and is that still in tact? (ie. the part the plugs into the wall).

"Pro"-tip: Test fuses with you multimeter using continuity mode.  A fuse may look ok, but you'll want that confirmation beep that is is good.

Hi Scrutineer. I've just had the same issue as you. Mecer 1200Va inverter on lead acid batteries for years.  Changed over to lithium battery and two weeks ago after our latest loadshedding the inverter pops.

I opened up at it looks like the rectifier bridge blew. It is a GBU 1010 unit. 1000V 10A. 

I'm going to see if replacing the blown part brings the inverter back. 

It seems that the charge circuit doesn't reach the lithium battery peak voltage and the system just keeps pushing power in.  This seems to result in the components being under load the whole time and eventually failing under thermal stress. 

Hope this gives you somewhere else to look to repair the unit.

On 2022/05/04 at 11:02 AM, CrzyEng said:

Hi Scrutineer. I've just had the same issue as you. Mecer 1200Va inverter on lead acid batteries for years.  Changed over to lithium battery and two weeks ago after our latest loadshedding the inverter pops.

I opened up at it looks like the rectifier bridge blew. It is a GBU 1010 unit. 1000V 10A. 

I'm going to see if replacing the blown part brings the inverter back. 

It seems that the charge circuit doesn't reach the lithium battery peak voltage and the system just keeps pushing power in.  This seems to result in the components being under load the whole time and eventually failing under thermal stress. 

Hope this gives you somewhere else to look to repair the unit.

If the rectifier blew, AC went down steam ... u384x(PWM driver IC) probably dead. The rectifier is the last component to fail in a overload condition. 

PM me if you have any repair questions.

The problem with lithium batteries are not how many amps or capacity they have ( they can not deliver the same peak amps as lead acid( BMS limited)) they can cause transient load spikes on the charging circuit of the inverter especially when battery charge mosfet's disconnect  for over volt or over cell protection.

For the statements or questions in this poste you can connect a inverter to any amount of amps and capacity battery. The protection (fuse, breaker) must be correct. The duty cycle of the charge circuit of these inverters are 100%. So they can charge a battery for a year if temps stay in spec.( Ambient and the fans work)      

 

ok it seems i'm not the only one who experienced this too.

Same story. 1200 mecer, with LA battery worked well for over 2 years.

Plugged in a brand new hubble s120 last month, and then last week, there goes the inverter! it wud not charge and then was doing some snap crackle and pop. RIP.

 

I'm getting a IVR1200 MPPT today. I hope this pairing works better this IVR1200 MPPT with the Hubble s120. 

Are there any specific settings I should be aware of? is it plug and play like my old mecer 1200? am i less likely to have the above issues as well with this new setup?

 

Thanks guys.

Ant

 

On 2022/07/01 at 1:33 PM, Pyro said:

ok it seems i'm not the only one who experienced this too.

Same story. 1200 mecer, with LA battery worked well for over 2 years.

Plugged in a brand new hubble s120 last month, and then last week, there goes the inverter! it wud not charge and then was doing some snap crackle and pop. RIP.

 

I'm getting a IVR1200 MPPT today. I hope this pairing works better this IVR1200 MPPT with the Hubble s120. 

Are there any specific settings I should be aware of? is it plug and play like my old mecer 1200? am i less likely to have the above issues as well with this new setup?

 

Thanks guys.

Ant

 

Heya

 

I just got this inverter yesterday and noticed that it doesn't like the bulk charging voltage(option 5) to be the same as the floating charging(option 6) when they're the same it charges at a lower power (~11A) on 25A mode and the voltage is pegged at 13.5V regardless of what you set it to.

I have a 200Ah Revov battery with this and setting the floating voltage one increment lower than bulk returns the charging to normal behavior, although mine is set to 13.8V to get 14.16V with the multimeter, so be aware of the voltage offset of about ~0.3V.

So far nothing has exploded, just thought I'd share my findings.

My battery is on User mode in option 02.

Regards

Ohan

Edited August 5, 20223 yr by Psynosaur

On 2022/07/01 at 1:33 PM, Pyro said:

ok it seems i'm not the only one who experienced this too.

Same story. 1200 mecer, with LA battery worked well for over 2 years.

Plugged in a brand new hubble s120 last month, and then last week, there goes the inverter! it wud not charge and then was doing some snap crackle and pop. RIP.

 

I'm getting a IVR1200 MPPT today. I hope this pairing works better this IVR1200 MPPT with the Hubble s120. 

Are there any specific settings I should be aware of? is it plug and play like my old mecer 1200? am i less likely to have the above issues as well with this new setup?

 

Thanks guys.

Ant

 

The settings that I got from Hubble for the S-120 are:
Battery Type: User-Defined 
Bulk charging: 14.4V
Low DC Cutoff: 11.2V
Float: 14.0V
Current: 25A

Does your fan stay on the whole time on the IRV-1200 MPPT? Hubble said that having an inverter that you can set the exact charging parameters is important, so I'm reluctant to go back to the 1200Va/750w inverter even though the fan turns off when its not charging. 

Hi .. I have recently acquired a Mecer 1200 (12V) and a Hubble 120 lithium battery. I was very mindful of the sudden demise of these inverters after some time when connected to lithium batteries, so monitored my system very closely. Lo and behold .. from time to time the fan would turn off when the battery voltage rose to around 13,5V .. after which the case would start to warm up. I therefore surmise that this is the precursor to the smoke coming out!

I can't imagine the reason for this but it would seem that some internal software mechanism assumes the battery to be charged and shuts off the fan .. not necessarily repeatable either which would explain why it seems to happen randomly. As a temporary fix I attached a computer type fan on the outside of the inverter (holes line up perfectly) and connected the fan to the battery terminals .. which is more a mechanical problem than electrical). The two fans now work in series. It works a treat but the fan can never be turned off. It has a power drain of 2W so not a big problem.

However, I would much rather keep the internal fan powered up while the mains is connected (this would cover the case whilst charging). Does anyone have experience of doing just that. I am prepared to waive the warranty to achieve that .. much more satisfactory than trying to return the unit for a repair, which would cost in the end.

7 hours ago, BigC said:

However, I would much rather keep the internal fan powered up while the mains is connected (this would cover the case whilst charging). Does anyone have experience of doing just that.

I don't have experience of doing that. But next to FAN CN6 I see FAN CN7 (unpopulated). Of the three pins, two are likely to have 12 V regulated (better than battery voltage, which can rise to over 14 V), so you may be able to use those pads (solder to them without even taking out the main board), to run either the internal fan on its own (it will be noisy running full blast all the time).

Alternatively, you could wire a small 12 VDC power supply to the AC-in terminals. That would run only when the AC-in is present, but not when in battery mode. You'd need to somehow "diode-or" the power. IF the fans aren't using PWM, that should be easy with just two power diodes. I don't know whether this model uses PWM control or not. With only 3 pins to the fan, it may not.

Hi Coulomb .. you are exactly right. I did just that and the fan does run flat out from a small 12V dc adapter. I discovered that the 3rd yellow wire is a form of speed indicator/sensor from the fan motor. Without that the inverter beeps and goes into fault mode. That impresses me as it means the functioning of the fan is monitored by the inverter as a crucial item. It is all working nicely. The one condition I could not test is .. what happens when the inverter shuts off the fan and the sense wire continues to send a voltage, which seems to be proportional to fan speed. Hopefully nothing, in which case the system should continue to work beautifully. 

Since you need access to that, you actually need to cut the fan wire and connect in a small piece of vero-board with the 2 diodes ORed.

I also reversed the fan as I have mounted the inverter vertically and it makes more sense to draw air in at the bottom and exhaust at the top. With all my experimenting and powering up and down continually, my regard for this little cheap inverter has increased many dBs.

I have noticed that the 12V dc stored on the caps does not bleed off, so I now connect the battery to the inverter terminal via a 10 Ohm resistor briefly to avoid that disturbing "snick" when connecting the battery. . . . chuckle!

13 hours ago, BigC said:

I have noticed that the 12V dc stored on the caps does not bleed off, so I now connect the battery to the inverter terminal via a 10 Ohm resistor briefly to avoid that disturbing "snick" when connecting the battery.

That's a very good idea; it avoids huge current surges into the capacitors, as well as blowing copper snot where it shouldn't go.

The splat is actually because the capacitors have discharged, so the battery is essentially connected across a short circuit for a short time until the capacitors charge up again.

Can i add an external battery charger to the batteries while using the inverter charger

8 hours ago, Dawid1 said:

Can i add an external battery charger to the batteries while using the inverter charger

@Dawid1Yes you can add a external charger. You can also add a extra MPPT to the charge the batteries. 

 

It may help to ensure that the external charger or MPPT has voltage settings about 0.1 V less than the inverter's bulk/absorb voltage setting. Otherwise, it can get confused and act strangely. i forget the exact scenario, but I found it worked better than way. I ran an external MPPT for several years, until I upgraded to a second inverter in parallel with the first.

On 2023/02/16 at 9:21 PM, Dawid1 said:

Can i add an external battery charger to the batteries while using the inverter charger

Good day good people, on the mecer 1200va 720w inverter, how do i turn off the low battery alarm?

Dear forum participants, I'm hoping someone can help. Mecer VA2000 UPS lead acid batteries x2 12V only lasted 5 months. Replaced with a single LiFePO4 lithium 24V 7AH battery. Discharge was spot on, 100WH. When the power came back on, allowing the UPS to charge the battery, the UPS failed. I reckon the x3 40A fuses blew out? Is is risky to replace with a larger fuse, and will this perhaps resolve the issue with charging the lithium battery?

 

Much appreciated,

Phantom computers noted the UPS is fine. Turns out the UPS is not designed to reboot after a lithium battery ran completely dead. Purchased a 24V 100ah charger to get the battery back up and running.
https://www.takealot.com/100ah-full-automatic-quick-battery-charger-12v-24v/PLID90405216

Trick is not to let the battery run dead completely.

 

Will confirm if the UPS revived after the blackout.

 

Thanks,

On 2021/06/18 at 10:52 AM, The_Scrutineer said:

Would the 200 litre tank not create twice gravity fed pressure vs the 2 x 100 litre tanks?

No it wont! The pressure is solely function of the water columns height behind it. Be it tanks of any size or only a small pipe. In the same sense an inverter only sees the voltage of the battery connected. The battery current is determined by the inverter in function of the load. If the battery capacity is too small its voltage will drop. If its well or even "oversized" it will behave well and keep the inverter happy. Your problem is definitely in the inverter. I could imagine a component (aging?) failure that just by coincidence happened when you changed battery.

Regarding In-rush current, your inverter will have an NTC (Negative Temp Coefficient) Thermistor in the Input section. This limits the inrush current that the main capacitors require to fully charge. This NTC is found in practically all SMPS units (Switch mode power supplies). Regards to all

9 hours ago, Cuan said:

This NTC is found in practically all SMPS units (Switch mode power supplies).

Yes, but an inverter is usually a lot more powerful than a switch mode power supply, e.g. 3-11 kW versus 300-750 W. Also the inverter typically operates at 24-48 V at around 100 A, whereas a SMPS draws only a few amps.

An inverter would suffer too much loss from using NTC devices. I doubt that they make NTCs with anything like 100 A rated current.

In this particular case, with a rated apparent power of 1200 VA, it might operate at nominally 12 V and some 100 A. Any voltage drop across an NTC would waste vast amounts of power.

When I still had one it kept tripping the power when load shedding ended and it would start charging. Did that for months until one day it never came back. This is what I found inside : 

 

That looks like the snubber resistor (taller grey resistor) and the two source resistors (green, shorter) resistors have been burning up over time. It might have started with the green resistors; these are used to sense the MOSFET current. If they changed resistance, that could have affected the peak MOSFET current, which would have worked everything harder, including the snubber resistor, but also likely the MOSFET itself and possibly other components.

But the start of the problem might have been some other components that failed, possibly gradually, and that caused these three (at least) to work harder and burn up.

As a point of interest, was the charge current roughly as expected, or too high or too low, after you restarted?

When I got it at the start of 2021 it was charging a 100AH Vision lead acid battery at 10A. Then when that battery died in 2022 I replaced it with two Joule 100AH gel batteries (in parallel), briefly upped the charging to 20A but the fan ran too loud, so I dropped it back down to 10A where it stayed until the inverter died in April this year.