inverter operating display black

non-EV Solar, Wind and other renewable power sources
non-EV batteries and other energy storage stuff
Forum rules
Important!
This forum is for discussion of Non-EV matters.
Post Reply
maximinus
Noobie
Posts: 23
Joined: Sun, 03 May 2020, 20:36
Real Name: Gerhard
Location: Vienna

inverter operating display black

Post by maximinus »

Hi all,
I sent following message to Mpp solar but would like to ask also here as I expect more profound answers here

Hi Eric,

today I found that the display on both inverters were black, although they are still operating as I can see from BMS and Coulombmeter. I disconnected them from main, panels and batteries but still no display after rebooting. Besides that watchpower on PC and via bluetooth cannot get connected. Any idea what went wrong ore how to solve this?

Regards Gerhard

a RaspberryPi connected to the inverters stopped working and does not boot anymore.

Is it possible that a surge destroyed something? we had no thunderstorm nor anything else.

Regards Gerhard
MPP5048GK 3,9 kWp
MPP5048GK 5,6 kWp
Battery 16S 300 Ah
48 m² Solar Panel
Heatpump 8 kW + 6 kW
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: inverter operating display black

Post by coulomb »

maximinus wrote: Thu, 18 Mar 2021, 23:10 today I found that the display on both inverters were black, although they are still operating as I can see from BMS and Coulombmeter. I disconnected them from main, panels and batteries but still no display after rebooting. Besides that watchpower on PC and via bluetooth cannot get connected.
All I can think of is a failure in one of the power supplies, e.g. +12V. This is needed by communications, though I thought not to the LC Display. Perhaps the LCD operates on 12 V but with 3.3 V signals, I don't know. There is a 50 V rated capacitor near the LCD connector on the control board, suggesting 12 V power.

Fortunately, the MOSFET drivers operate off 15 V, a separate power supply (derived from a different "transformer" winding). The DSP itself operates at 3.3 V and 1.8 V, both derived from a 5 V power supply.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
maximinus
Noobie
Posts: 23
Joined: Sun, 03 May 2020, 20:36
Real Name: Gerhard
Location: Vienna

Re: inverter operating display black

Post by maximinus »

GK LCD Display Check 20190821.pdf
(952.5 KiB) Downloaded 72 times
@coulomb

Thanks for your input. Will check when I answer MPPs request:
1.Please provide us serial label photo of these two inverters.

2.When this issue occurs, please provide us clear photo to show the LCD display condition.

3.Please follow this guide (GK LCD Display Check 20190821.pdf) to check these resistances of comm board and remote comm board then send us the result.
MPP5048GK 3,9 kWp
MPP5048GK 5,6 kWp
Battery 16S 300 Ah
48 m² Solar Panel
Heatpump 8 kW + 6 kW
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: inverter operating display black

Post by coulomb »

maximinus wrote: Sat, 20 Mar 2021, 01:01 GK LCD Display Check 20190821.pdf
Wow. They seem to have gone to a lot of trouble to produce that PDF, and it looks like it's just for you. Unless this is a more widespread problem.

They also seem to suspect different hardware than I did, although their measurements are easier and safer than mine would be.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
maximinus
Noobie
Posts: 23
Joined: Sun, 03 May 2020, 20:36
Real Name: Gerhard
Location: Vienna

Re: inverter operating display black

Post by maximinus »

although their measurements are easier and safer than mine would be
It appears that pdf was already prepared, this is not only me with display problems. I suspect that these measurements concern the backlight but may be the missing communication. My resistor values of these 1 Ohm resistors are only 0,2 Ohms and the voltage across the photocoupler 1 do not correspond. What else is interesting the voltage across this 2pin connnecor between mainboard and communication board which was of no concern by them is in one case 16V in the other 0V but both displays dark. Hopefully they can help with some advice. Keep you infomed as soon as I receive something.
Have a nice day
Gerhard
MPP5048GK 3,9 kWp
MPP5048GK 5,6 kWp
Battery 16S 300 Ah
48 m² Solar Panel
Heatpump 8 kW + 6 kW
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: inverter operating display black

Post by coulomb »

maximinus wrote: Sat, 20 Mar 2021, 18:22 My resistor values of these 1 Ohm resistors are only 0,2 Ohms ...
Those are actually fuses I believe, in which case 0,2Ω is fine.
and the voltage across the photocoupler 1 do not correspond.
Did you use diode range on the multimeter, and check both directions?
What else is interesting the voltage across this 2pin connnecor between mainboard and communication board which was of no concern by them is in one case 16V in the other 0V but both displays dark.
Was that a DC or AC measurement? Power supply to the comms board is a roughly 15 V p-p square* wave, which they send to the transformer and rectify and filter the output to generate the various voltages needed by the circuit. But I would think that it should measure non-zero on either a DC or AC multimeter range.

* Edit: it's probably not a square wave, since they use flyback circuits for the various power supplies.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
maximinus
Noobie
Posts: 23
Joined: Sun, 03 May 2020, 20:36
Real Name: Gerhard
Location: Vienna

Re: inverter operating display black

Post by maximinus »

Did you use diode range on the multimeter, and check both directions?
No, therefore I repeated the measurement and found that in one case the voltages are correct 0,58/1,09 Volt in the other case -0,67/+0,69 in diode and normal range. The measurement is indipendent of the state of the power pushbutton. Thank you for the advice, I did not realize that this side is the diode
Was that a DC or AC measurement?

It is definitely DC but it depends on the state of the pushbutton: if it is unpressed (off?) then the reading is 16,2V /14,88V
When it is pressed both are 0V. Maybe this connection has a other meaning and is not the powersupply.

Expect with inerest the response of MPP Solar.
Regards Gerhard
MPP5048GK 3,9 kWp
MPP5048GK 5,6 kWp
Battery 16S 300 Ah
48 m² Solar Panel
Heatpump 8 kW + 6 kW
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: inverter operating display black

Post by coulomb »

maximinus wrote: Sun, 21 Mar 2021, 22:06 I repeated the measurement and found that in one case the voltages are correct 0,58/1,09 Volt in the other case -0,67/+0,69 in diode and normal range. The measurement is indipendent of the state of the power pushbutton.

Those measurements are meant to be taken with the power off. The multimeter battery provides a small test current, and measures the resultant voltage drop.
When it is pressed both are 0V. Maybe this connection has a other meaning and is not the powersupply.
The button is a soft button, it's just a digital signal to one of the processors. Pressed means turn on the DC-AC converter or AC relay to power the loads. Unpressed means don't power the loads, but don't power down for one minute, and even then only if there are no charging sources. So that explains the presence of voltage when the button is unpressed, but not the zero volts when pressed. Perhaps the power supply is weak, and collapses when there is a higher demand, e.g. when the DC-AC converter comes on. But I don't see why only the HFPW supply would be affected, with the rest of the inverter appearing to work.

Edit: 12V -> HFPW. HFPW means high frequency power, used to power things like the communications board, paralleling board, etc.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
maximinus
Noobie
Posts: 23
Joined: Sun, 03 May 2020, 20:36
Real Name: Gerhard
Location: Vienna

Re: inverter operating display black

Post by maximinus »

Hi coulomb,

I would like to inform you that MPP agreed to replace "comm board" and "remote comm board", whatever the last one may be, free of charge. Unfortunately I could not convince them to give me some information how I could check if the vertical board inside the inverter or else is defective. I hate it to replace some parts without knowing the reason. I fear that the replacement parts may be damaged again when this board is defective. According to your experience is my fear unsubstantiated?
Or do you know what voltages/waveforms should be measured on this 6pin connector to confirm the board is OK?
Do you have the circuitry ore service manual of the GK inverter.

Many thanks for your support
Gerhard
MPP5048GK 3,9 kWp
MPP5048GK 5,6 kWp
Battery 16S 300 Ah
48 m² Solar Panel
Heatpump 8 kW + 6 kW
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: inverter operating display black

Post by coulomb »

maximinus wrote: Fri, 26 Mar 2021, 20:38 I would like to inform you that MPP agreed to replace "comm board" and "remote comm board", whatever the last one may be, free of charge.
Well, that's good, and it may fix your problems.
Unfortunately I could not convince them to give me some information how I could check if the vertical board inside the inverter or else is defective.

The vertical board is the control board with the main Digital Signals Processor. It and the main board would be hard to test by the owner.
I hate it to replace some parts without knowing the reason.
They possibly suspect that one or other of these boards is faulty, in such a way that it's dragging down one or both 12V power supplies. Whether the power supply was also damaged or not remains to be seen. The other thing is, these boards are small, inexpensive, and relatively easy to ship and install by savvy customer. So it's a fairly cheap gamble for them.
[ Edit: thinking about this now, I realise that the comms and display boards probably generate their own plus and minus 12V from high frequency power. But maybe it's the high frequency power that is being dragged down. ] [ Edit 2: No dragging down necessary; one or other of them has likely failed without disturbing the main power supply. ]
I fear that the replacement parts may be damaged again when this board is defective. According to your experience is my fear unsubstantiated?
I think that the chances of that are very low. Whatever damage happened is unlikely to spread now.
Or do you know what voltages/waveforms should be measured on this 6pin connector to confirm the board is OK?
Do you have the circuitry or service manual of the GK inverter.
No, all my experience so far is based on the PIP-MS models. The remote comms board for example (it distributes serial comms to and from other boards) only exists on models with the removable display. [ Edit: Oops, I think they call the communications distributor board the "comms board", and "remote comms board" is probably the whole removable display, with the LC Display on it. I was somehow thinking LC Display driven by the control board, as with the PIP-MS models. Sigh. ] I recently obtained an MK/King, so maybe there might be more schematic traces for such things eventually. When at the computer, I'll check my collection for an MK service manual. I'm doubtful.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: inverter operating display black

Post by coulomb »

coulomb wrote: Sat, 27 Mar 2021, 07:15When at the computer, I'll check my collection for an MK service manual. I'm doubtful.
As I suspected, I don't have a GK service manual in my collection. The closest would be a MK (King) service manual; ignore anything related to paralleling or the PFC module. You can read a web version here, or download a PDF file here.

On perusing this, I realised that they call the comms board in these models the new board that distributes communications to/from other boards. Also, I was thinking that the LCD was driven by the control board, as it is with PIP-MS models, but of course you have a removable display (Voltronic call it a remote display, but that's too easy to confuse with a totally different product for MS style models). As a result, a lot of my previous answers were muddled, sorry!

So now I'd say you should be fine with the boards they will be sending you. You might not even have to install the comms (distribution) board at all; the LC Display might be the only fault.

For your own satisfaction, the 6-pin connector(s) at the comms board may use the same pinout as the PIP-MS series, most of which is documented in this partial schematic trace of the PIP-MS comms board (quite different, but the comms connector could be the same). Mainly look at the lower left part near CN3. My guess is that unlike the PIP-MS board, the removable display takes its power from HFPW+ with GND as the return (HFPW- on the PIP-MS board).

As a point of interest, were you using the removable display remotely, or was it still "docked" at the bottom of the GK? I'm wondering if lightning or a power surge of some sort induced a transient into the long wires. Even if you had something plugged into the RS-232 and/or RS-485 ports of the removable display, they might have allowed a transient to get into the removable display unit and damage it. It seems unlikely, but at least it's a possible explanation of how it failed.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
maximinus
Noobie
Posts: 23
Joined: Sun, 03 May 2020, 20:36
Real Name: Gerhard
Location: Vienna

Re: inverter operating display black

Post by maximinus »

@coulomb
as a point of interest, were you using the removable display remotely, or was it still "docked" at the bottom of the GK? I'm wondering if lightning or a power surge of some sort induced a transient into the long wires. Even if you had something plugged into the RS-232 and/or RS-485 ports of the removable display, they might have allowed a transient to get into the removable display unit and damage it. It seems unlikely, but at least it's a possible explanation of how it failed.
One the displays were acually remote the other still docked inside converter. Both were connected to a PC via serial to
USB converter and both were connected to a RaspberryPi with the program "Solaranzeige" running on it via USB cable. By
the way the Raspberry is also damaged as it does not boot any more and his SD card does not boot in a replacement
Raspberry.
I tried to remember what happened shortly before the incident.
As I told you before I purchased a Dieselgenerator single phased to supply a batterycharger to recharge the battery in
case of missing sun. In a testrun this worked well and the battery got charged with 50Amps until the BMS switched off
due to endvoltage reached.
As the generator is located in a garage I had to provide a hole in the concrete wall to feed the exhaust into the
outside. This is a corrugated hose made of stainless steel. I wanted to arrange this hose anew and when I pulled this
hose back out of the hole while the generator was still running (but charger switched off on secondary side to battery)
I saw some light between concrete hole and hose which I identfied later as some DC arc. Actually there was a DC voltage
of 45V between ground of generator and ground of installation. This was caused by the fact that this charger had a
common ground connection with the +5oV terminal which I later removed. The switch disconncts the -50V.
Both inverters operated after this incident well as it was seen on the display of the BMS but their own displays were
black. I cannot imagine what happened as it was functional earlier but it may be the reason.

Regards Gerhard
Attachments
IMG_20210327_193716.jpg
IMG_20210327_193716.jpg (93.77 KiB) Viewed 1096 times
IMG_20210327_193634.jpg
IMG_20210327_193634.jpg (125.55 KiB) Viewed 1096 times
IMG_20210327_193631.jpg
IMG_20210327_193631.jpg (135.71 KiB) Viewed 1096 times
IMG_20210327_193730.jpg
IMG_20210327_193730.jpg (112.87 KiB) Viewed 1096 times
MPP5048GK 3,9 kWp
MPP5048GK 5,6 kWp
Battery 16S 300 Ah
48 m² Solar Panel
Heatpump 8 kW + 6 kW
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: inverter operating display black

Post by coulomb »

maximinus wrote: Sun, 28 Mar 2021, 03:27 Actually there was a DC voltage
of 45V between ground of generator and ground of installation. This was caused by the fact that this charger had a
common ground connection with the +5oV terminal which I later removed. The switch disconncts the -50V.
Wow. The difference between grounds does sound like the source of the problem. The fact that the Pi was also damaged at the same time is a further indication.

I occasionally come across chargers that earth one output, but it's always the negative output. [ Edit: but none of them were 48V chargers. ] My one charger that is still like that is clearly marked "UNISOLATED!". It can cause so many problems.

I hope that your system performs properly with the connection to earth removed. From one of the photos, it looks awkward to change, because the case seems to be very close if not touching the +Common terminal.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
paulvk
Senior Member
Posts: 457
Joined: Fri, 23 Oct 2015, 23:45
Real Name: Paul
Location: Sydney

Re: inverter operating display black

Post by paulvk »

Positive ground is the norm in 48v dc as 90% of equipment is for telecommunications use where the standard is positive ground.
maximinus
Noobie
Posts: 23
Joined: Sun, 03 May 2020, 20:36
Real Name: Gerhard
Location: Vienna

Re: inverter operating display black (now solved)

Post by maximinus »

The inverters are OK now after replacing the boards. The only problem is that the bluetooth connection is not functioning. The App indicates a established connection as it displays the correct number of both inverters, says connecting now and confirm connected, but all data- and parameterfields remain empty. Watchpower receives these data as does solpiplog. Strange.
Regards Gerhard
MPP5048GK 3,9 kWp
MPP5048GK 5,6 kWp
Battery 16S 300 Ah
48 m² Solar Panel
Heatpump 8 kW + 6 kW
User avatar
coulomb
Site Admin
Posts: 6357
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: inverter operating display black (now solved)

Post by coulomb »

maximinus wrote: Thu, 22 Apr 2021, 07:50 The only problem is that the bluetooth connection is not functioning... but all data- and parameterfields remain empty.
Is it possible that the Bluetooth board isn't connected to the data distribution board? It's a smallish PCB inside the inverter that has several RJ-45 sockets on it. A cable might have ended up not connected after the replacement of other boards.
MG ZS EV 2021 April 2021. Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
Patching PIP-4048/5048 inverter-chargers.
If you appreciate my work, you can buy me a coffee.
Post Reply