Inverter Man

Yes unit will still be functional as a ups after you removed the mppt/pmw scc...Will keep this post updated as I continue to figure this out I repaired more than 60 units the past 18months https://www.facebook.com/inverterman911 ,...the only units in the past that i could not repair was this Mppt fault that only shows 5w charge from mppt.... I cant seem to get my head around it

Thanks for the quick response I appreciate your willingness to help Coulomb I did download the pdf of your schematics and traced all tracks and components according to the circuit diagrams...all measured as expected. I will have a look at the powersupply around the switching transformer...I will probably have to remove all caps and measure the capacitance of each cap. ...can you tell me what causes discoloration of solder joints...I use flux when I resolder so that my joints look more profesional, but for some reason the solder joints won't shine...its a darkish colour

Mppt relays stopped disconnecting but generation alters between 0 watt and 5 watt... As soon as more curent are being drawn the relays disconnect again

Mppt relays stopped disconnecting but generation alters between 0 watt and 5 watt

Had to repair track with aliminuim foil,...but I also noticed that the solder joints looks a bit dark in color

Hi Coulomb, it is a 145Voc Mppt 80amp and Im refering to the + side of the mppt not the 400v that will give me a shock if I touched it while it is energised(out put was switched off when I aplied presure on the mppt board) I will add some photos later, and definitely look at the smd caps you are refering to as well as the track cracks Modina mentioned PS. I think Modina means that the pv voltage is bucked down to battery charge voltage And you mean that the Pv current is boosted to charge battery/supply load Both sound correct to me

Hi Coulomb, it is a 145Voc Mppt 80amp and Im refering to the + side of the mppt not the 400v that will give me a shock if I touched it while it is energised(out put was switched off when I aplied presure on the mppt board) I will add some photos later, and definitely look at the smd caps you are refering to as well as the track cracks Modina mentioned PS. I think Modina means that the pv voltage is bucked down to battery charge voltage And you mean that the Pv current is boosted to charge battery/supply load Both sound correct to me

Thanks for explaining the operation of a mppt so eloquently I will take some photos and add it to the post I think the mosfet cuircuit is fine because pv watts increase on the display when I apply my finger between the smd fet (that applies voltage to the relay coils) and the + bus sensing circuit of the mppt

Hi everyone thanks for this awesome forum and for accepting my request to join I have a Mppt that switch relays on then off again.PV voltage(85v) drops to battery voltage as soon as relays engage. The panel icon on screen disapear for a second and then reappear, as soon as panel icon connect to battery icon it switch off again...and it continues like that I had a look at the positive bus where relays switch to and found that when I press my finger on the sensing circuit the fault goes away and mppt operates as expected. I then concluded that it must be a dry joint..and proceeded to check all components and track continuity in that specific area where I pressed my finger...all values measured correct I then proceeded to find out why when pressing my finger on this part of the pcb will it cause the circuit to operate, I then found a clue on stack exchange website...something to do with capacitance or noise that is reduced by pressing/touching with finger... Solution to this seems to be to connect a cap between effected area and ground Is there anyone here that can enlighten me as to what cap I need to use and exactly where to connect it

Hi everyone thanks for this awesome forum and for accepting my request to join I have a Mppt that switch relays on then off again.PV voltage(85v) drops to battery voltage as soon as relays engage. The panel icon on screen disapear for a second and then reappear, as soon as panel icon connect to battery icon it switch off again...and it continues like that I had a look at the positive bus where relays switch to and found that when I press my finger on the sensing circuit the fault goes away and mppt operates as expected. I then concluded that it must be a dry joint..and proceeded to check all components and track continuity in that specific area where I pressed my finger...all values measured correct I then proceeded to find out why when pressing my finger on this part of the pcb will it cause the circuit to operate, I then found a clue on stack exchange website...something to do with capacitance or noise that is reduced by pressing/touching with finger... Solution to this seems to be to connect a cap between effected area and ground Is there anyone here that can enlighten me as to what cap I need to use and exactly where to connect it