PowMr 5000w all-in-one has the MPPT cycling at dawn and dusk

[andrewgokart]

I tried searching for this online and on here, but can't seem to find anyone who has an explanation for what I am seeing. I have 9 panels, 100w each, in series for roughly 205v going in to my PowMr 5000 watt all in one inverter. At Dawn and Dusk, the charge controller is displaying 205volts on the PV (195-205ish) and then will connect, begin charging the batteries and the voltage of the PV array will drop as amps goes up. The voltage drops down to around 85 volts and then it disconnects the PV array and stops charging. Then seconds later, it repeats this whole thing. OVER AND OVER AND OVER AGAIN until the sun is fully up or until it's fully down and there is no light. Is this normal??? It's basically just cycling the charger over and over and over again. In the time-span of 1 minute, it probably does this 2-3 times.

 

[sunshine_eggo]

Sounds like a faulty or really shitty MPPT sweeping algorithm.

Once the sun is up, does it maintain steady charging/power proportional to the available solar?

 

[Vigo]

Yes, this is normal. Most high-voltage MPPTs have a ‘minimum’ voltage around 100v. Solar panels will make nearly full voltage under surprisingly weak light, but once you start to pull current that voltage crashes quickly and the combination of the volts X amps does not amount to much in watts.

So yes, its normal. Now some mppts might be more irritating about it than others. Ihave a Powmr that beeps when it loses solar for the day, but thankfully it only seems to do it once! My growatts do that every morning and evening too but unless im watching it i uave no idea its happening. It doesnt bother me in either of my cases. Sometimes the notifications are selectable in settings.

 

[Bud Martin]

My MPP Solars do the same, the panels produce enough Voltage to wake up the unit but not enough current to keep the unit alive so the panels Voltage drops.

 

[andrewgokart]

Thanks. I figured it would be better to have the voltage stay high and draw the power that it can from the array instead of constantly switching it on and off. I would think it would just hold the voltage somewhere in the middle.

As for the beep, go through your settings and I bet you can disable it! I did on mine. So so annoying.

 

[andrewgokart]

Sounds like a faulty or really shitty MPPT sweeping algorithm.

Once the sun is up, does it maintain steady charging/power proportional to the available solar?

Yes, it maintains once there is more direct sun on them. So I assume it's working correctly. I just think it's really annoying for whatever reason. (It doesn't actually do anything that annoys me, I just don't like the fact that it does this cycling). I would think there is a more efficient way to hold a steady voltage and let the tiny amount of current it produces flow to the battery/load. Is the cycling bad for the batteries??

 

[Vigo]

I am guessing here, that the mppt uses battery power to initiate its operations and if the power harvested from the array isn’t a ‘net gain’, it will stop trying rather than slowly drain your battery with pointless PV operations. That’s a guess! I bet if you watch current during these sweeps it is absolutey tiny.

 

[v_green57]

Had this very same thing happen with a MidNite MN5048 but in my case it was happening on a very overcast day with little to no solar output. I took a video of it and my neighbor discussed it with MidNite.

Answer: "normal behavior".

To expand on this:

A large percentage of AIO's are made by the same outfit in China. Name escapes me now but somebody will know it. The PowerMr and the MidNite are probably basically the same unit.

Anyway, and this is my opinion only, if you come from a background of separate charge controllers that have highly optimized MPPT charge algorithims, you will be very disappointed in those of the AIOs.

To put it simply, they suck.

There was a MidNite Classic as part of the same install using another array, and at the same time under the same conditions, was outputting a steady small charge. No roller coaster.

AIOs are cheap and you get what you pay for. The lame-a$$ MPPT behavior coupled with the 70-100W "idle" consumption has removed them from consideration in my case.

I do, however, actively watch how things evolve and hope they will improve.

 

[andrewgokart]

Had this very same thing happen with a MidNite MN5048 but in my case it was happening on a very overcast day with little to no solar output. I took a video of it and my neighbor discussed it with MidNite.

Answer: "normal behavior".

To expand on this:

A large percentage of AIO's are made by the same outfit in China. Name escapes me now but somebody will know it. The PowerMr and the MidNite are probably basically the same unit.

Anyway, and this is my opinion only, if you come from a background of separate charge controllers that have highly optimized MPPT charge algorithims, you will be very disappointed in those of the AIOs.

To put it simply, they suck.

There was a MidNite Classic as part of the same install using another array, and at the same time under the same conditions, was outputting a steady small charge. No roller coaster.

AIOs are cheap and you get what you pay for. The lame-a$$ MPPT behavior coupled with the 70-100W "idle" consumption has removed them from consideration in my case.

I do, however, actively watch how things evolve and hope they will improve.

My first venture into solar was a Renogy MPPT unit that I hooked up to a 12v battery and was able to provide a charge with hardly any sun out at all. (and then sold that because that was too expensive for me at the time). So that's what I was comparing my AIO to. I see what you're saying, though. Wish I had a 48v MPPT and I would probably just have that hooked directly to the battery ha. I got all my current equipment dirt cheap though auctions, so that's the only reason I'm venturing into this. Not trying to spend a whole bunch of money to replace any equipment.

Thanks for the response! And "rollercoaster" is a great way to describe what it's doing.

 

[v_green57]

Here's the AIO manufacturer I mention above:

Global Leaders in Residential Energy Storage Solutions-SRNE

www.srnesolar.com

I would say over half the AIOs on Amazon are rebranded SRNE's.