PIP-4048MS and PIP-5048MS inverters

[coulomb]

Re batteries , has anyone used the cells (blades) from Prius for home use.

The ones I have are NiCd, at about 7.2 volts per blade

I thought that all the prismatic cells were NiMH (Nickel Metal Hydride). These are particularly difficult to charge safely, so I believe that they are rarely used in DIY projects (EVs or solar energy systems). At least one G2 Prius that was converted to plug-in caused a fire. (It's not certain what caused the fire, but it shows how dangerous this chemistry can be, if not handled very carefully.)

[ Edit: Nickle -> Nickel ]

[solamahn]

I use CALB CA400's. Trick is to choose very similar Ah rated cells to make up the bank. I am balancing 8 cells now to connect to a 2424mse. The 8 cells range from 430.0Ah to 430.7

[offgridQLD]

Interesting Solarmahn. 430ah is a healthy head start. Like you say as long as they are consistent. And stay consistent for that matter.

I use the same 400ah cells but 16 of them. I didn't do a full DOD capacity test when new. Though I did carefully top balance them and now 2 1/2 years on they are still well balanced with manual top balancing every few months.

Typical overnight discharge has me at around 25 - 30% DOD overnight. (basing it on 400AH nominal capacity) Though in real bad weather or the odd time we have needed our Ev charged overnight or I forgot to turn off the irrigation pump all night...oops!) we have seen 60 - 70% DOD a few times worst case but uncommon.

Who knows how long the cells will last I hope for 10 years and they are getting a easy life, refrigerated conditions conservative charge settings and for there size modest discharge demands.

Perhaps not the best economics to oversize the pack and not ring every ah from the lithium cells but I still like the idea that as the cells capacity shrinks. lets say by 30% at the 8 year mark (made up number) the reserve capacity is still within my average overnight consumption scope.

That said I would want any bigger than 400ah 16 cells. They replaced 1330ah of lead acid so three times smaller.

6MDX,
     I do see your point as you get older at some point almost everything has a life time warranty

[solamahn]

Some of them are 440Ah. I only take them up to 3.39v for top balancing

[TonyB]

Finally got around to retrying the reflash. Started with a rebooted laptop, so no comm issues. Powered down inverter, disconnected house loads and solar panels, no mains input. Restarted inverter - all OK - started reflash - after 10 seconds a clunk from the inverter - after another 20 secs a pop-up error message says 'Can't communicate on comm 7. In reflash panel it says comm 7 started. Inverter is now frozen - only option is to disconnect battery and reconnect - Inverter then starts up normally.
Note that there was no 2nd clunk from inverter. In second attempt, after freezing I did try to run reflash program but it just returns a 'can't open comm 7' error.
Any suggestions?

[weber]

TonyB, What's the model number on the side of the inverter? Are you certain the clunk is coming from the inverter and not a nearby contactor? I'm not aware of anything inside the PIP-4048MS that would produce a clunk sound, only relays that would produce a click. Can you confirm that there is still battery voltage at the battery terminals of the inverter after the clunk?

[coulomb]

... - started reflash - after 10 seconds a clunk from the inverter - after another 20 secs a pop-up error message says 'Can't communicate on comm 7. In reflash panel it says comm 7 started. Inverter is now frozen - only option is to disconnect battery and reconnect - Inverter then starts up normally.

The fact that it starts up normally indicates that it can't have started the re-flash process for real. One of the first things it would have to do would be to erase the first flash segment (possibly all of them at once apart from the one holding the DSP bootloader code), and there is no way it could run normally with at least a seventh of its code missing. There are 8 flash sectors, and a sector is the smallest unit that can be erased; one sector holds the bootloader.

So either the inverter/charger is the wrong model, or comms stops getting through somehow after the very start. Perhaps no comms is getting back from the inverter/charger back to the PC, so the PC never proceeds to the point where flash is erased.

My bet would be the latter (no comms is getting back to the PC). Does watchpower work on this PC and inverter/charger? Can you use a terminal program to do say a QPIGS command (general status command)?

[ Edit: the other possibility is that WatchPower or some other communications program is already running, and is interfering with the flash process. Makew sure you have done a File/Exit, not just close the window. Generally Windows won't allow more than one program to take control of a serial port at once, however. ]

[coulomb]

By my analysis, if the PC does not receive an acknowledgement from the inverter/charger after 10 attempts, it will throw up a message box with this exact text: "Can not open serial port".

TonyB: is this what you get?

[TonyB]

Guys, Thanks for your responses. Answers to questions posed - Inverter model name = Inverter 5KVA-48-PAR-A, serial = 92931608100021 (sorry couldn't post picture).

Certain the clunk is from the inverter, there are no contacters or similar in use externally. Yes battery power still present.

Watchpower works on this inverter, using the same usb/serial cable, had restarted laptop to avoid comm port clashes. Will try a terminal program on next visit.

Last question, that might have been the wording but will have to recheck on next visit. The error message I saw was in a separate window from the reflash software window.

[weber]

Inverter model name = Inverter 5KVA-48-PAR-A

I was expecting more. Does it have "Axpert KS" or "Axpert MKS" somewhere on the label? Or just "KS" or "MKS"? Failing that, do you know whether its built-in solar charge controller is PWM or MPPT? Failing that, can you find from its manual what is its "Maximum open circuit PV array voltage"? 105 Vdc or 145 Vdc?

What does it say for Manufacturer?

I suppose it's possible that "-A" means MPPT and "-B" means PWM or vice versa. In which case we will need to update the list of inverter model names that this thread is about, and that our patched firmware is suitable for.

[TonyB]

Weber, No there is no indication of manufacturer either on the inverter nor in the manual, only a 'Made in China' at the bottom of the label. It is an MPPT solar controller and the Panel Voc is 145V. It is running software version 72.60 and solar software is 04.10. So in all respects it looks like and acts like the Axpert, but maybe it is a clone that has slightly different reflash parameters???

[lopez]

Hi Tony,

Where did you buy it from?

[coulomb]

Weber, No there is no indication of manufacturer either on the inverter nor in the manual, only a 'Made in China' at the bottom of the label.

Yes, I've noticed that on many OEM'd machines. Frustrating.

It is running software version 72.60 and solar software is 04.10. So in all respects it looks like and acts like the Axpert

I have to agree.

but maybe it is a clone that has slightly different reflash parameters???

Possible I suppose, but it feels unlikely to me. The fact that it responds to the command from the Reflash software (by ignoring the buttons, for example) is a strong indication that these two are meant to talk to each other.

You mentioned that WatchPower works with your cable... is this through a USB to RS232 converter, plugged into the RS232 input of the inverter/charger, using the supplied DE9 to RJ-45 cable? Not through the USB port? I believe that the Reflash Tool won't work through the USB port, but Watchpower can, so Watchpower could still be working (through the USB port) while the RS232 port has issues.

Finally, is it possible to try some another USB to RS232 adapter? Some are created better than others. Those with FTDI and Silicon Labs chipsets are supposed to be better, and ProLific are supposed to be worse, but Weber and I have never had trouble with the ProLifics (apart from the driver issue; they changed the drivers to overcome some cheap knock-off problems, but if it talks at all, the ones we get here in Australia, at least from the local company Jaycar, seem to be good).

[Ian60D]

Thanks Weber,
              I gave that setting a try today but I get the same behavior from the PIP.

30A works perfect but set it at anything more and it will fall back (typical around 38 - 43A. Voltage and frequency from the generator all look stable. No errors I can see each time it drops to 0 amps and starts ramping up again.

I guess one experiment I could try is connecting the new PIP to a separate 40ah 48v lithium bank to power it and then feed it AC input from a 15A wall outlet (That's powered by my selectronic inverter) and see if it will then charge the 40Ah 48v bank at over 30A stable. This would eliminate any fussy Ac input issues it could have with my generator.

A bit of messing around but only option now I am full time offgrid.

I have just set up one of my units as a battery charger. Is has exactly the same behaviour.
1000AH Gel battery bank. Haven't connected the solar yet as it is set up as 24 V and I need to rewire it. Gen set is a Honda EX5500 Not an inverter gen but very stable. Runs everything else electronic I have tried just fine.

[offgridQLD]

Yes it would be interesting to hear from some one who is able to sucsefully charge with the PIP at the full 60A from a genset or even mains as a starting point.

I haven't had a chance to play with it more.

[TonyB]

Guys, We've had another go at trying to reflash, this time with a different Serial/USB cable - no change. The error message coming back is "Can not open serial port", so it looks like you are right in that no serial communications are getting back to the reflash program. Did also look at trying the USB cable but the reflash program only offers a choice of serial port - so no go there. Forgot to try the QPIGS whilst we were there, sorry. For your info I have attached photo of the label, below. Am still trying, through local seller, to establish who the importer/ditributor is (based in Seville)

[Ian60D]

Will test it on mains power if it's happy to charge at more than 30a from that then I will move on to tweaking generator settings to get closer to 240v and 50hz.

Did you actually try this? Do you have mains available? I don't so can't try it.

Of minor note. When I first set it to the higher current it ran at that for some minutes. Maybe 10 or more. It then started to drop out and ramp up.
I wonder if some sort of self protection is going on.
My gen set has voltage regulation and I have it set at 230V and it is stable at that. The Hz is a little high at 53. Thogh both these were from the pip display. I will check when I have time with the fluke and also adjust the gen set speed to get the Hz correct. Based on your experience I doubt it will change things though. Is your unit from MPP Solar? What firmware version?

[Ian60D]

BTW all the manuals for the mpp stuff is here.
http://www.mppsolar.com/manual/

[ Edited Coulomb: removed space from URL tag ]

[coulomb]

When I first set it to the higher current it ran at that for some minutes. Maybe 10 or more. It then started to drop out and ramp up.
I wonder if some sort of self protection is going on.

Reading that gave me a thought. Inverters require an inductor between the inverter output and the mains to be able to send power into of out of the inverter's "output". The phase difference between the inverter's output and the mains determines the magnitude and direction of power flow. So there will be significant (~ 6% of 240 V = 14 V) of 50 Hz in that inductor. Which inductor would that be? It has to be the large toroidal one that is connected to the inverter's output. The one Weber noticed gets really hot, and tried to re-wind with litz wire. (See the index for the whole interesting saga, in case you missed it.)

It seems to me that this inductor's core isn't designed for low frequency, and it already gets quite hot (some 100°C). So maybe when the inverter is inverted (so it becomes a battery charger) and there is significant 50 Hz in that inductor, it gets really hot. There are three temperature sensors in the inverter, one of them may sense the temperature of this inductor, or perhaps they infer it from its resistance somehow. The firmware may be forced to cut back the power to the mains battery charger when this inverter gets really hot.

I don't have time right now, but perhaps someone could carefully and safely measure the temperature of that inductor when mains battery charging? Even watching the temperatures from a Q1 command (see index) might be interesting.

[weber]

Reading that gave me a thought. Inverters require an inductor between the inverter output and the mains to be able to send power into of out of the inverter's "output". The phase difference between the inverter's output and the mains determines the magnitude and direction of power flow. So there will be significant (~ 6% of 240 V = 14 V) of 50 Hz in that inductor.

You're thinking of the kind of inverter that can smoothly go from taking power out of the mains to putting power into the mains. But the PIP never puts power into the mains. So it has no need for, and does not have, a 50 Hz inductor.

Which inductor would that be? It has to be the large toroidal one that is connected to the inverter's output.

That inductor is for blocking high frequency PWM. I expect it is designed to be as close to a short-circuit as is practical, for 50 Hz.

The one Weber noticed gets really hot, and tried to re-wind with litz wire. (See the index for the whole interesting saga, in case you missed it.)

I not only tried, I succeeded. And the inductor did run cooler.
viewtopic.php?title=pip4048ms-inverter& ... 332#p63996
The disappointment was that it didn't reduce the no-load power consumption.

It seems to me that this inductor's core isn't designed for low frequency, and it already gets quite hot (some 100°C). So maybe when the inverter is inverted (so it becomes a battery charger) and there is significant 50 Hz in that inductor, it gets really hot. There are three temperature sensors in the inverter, one of them may sense the temperature of this inductor, or perhaps they infer it from its resistance somehow. The firmware may be forced to cut back the power to the mains battery charger when this inverter gets really hot.

I happen to have a PIP apart at the moment, so I checked. There is no temperature sensor anywhere near that inductor. And I severely doubt that they would have added the PWM-filtering circuitry required to measure its 50 Hz resistance, when adding a single thermistor near it (as they have done with the HF transformer) would be so much simpler.

I don't have time right now, but perhaps someone could carefully and safely measure the temperature of that inductor when mains battery charging? Even watching the temperatures from a Q1 command (see index) might be interesting.

I hope it is clear now, that measuring the inductor temperature would be a waste of time.

[Ian60D]

Is someone able to test charging from the mains. In my case I have No PV or AC loads connected. The unit was turned on however. So mains charging battery with output (no load) In Bypass mode. Anything over a 30A charge rate triggers the problem. The unit doesn't appear to get warm from the outside even after 8 hrs of charging and the fans stay at low speed.

Cheers Ian

[offgridQLD]

Did you actually try this? Do you have mains available? I don't so can't try it.

Of minor note. When I first set it to the higher current it ran at that for some minutes. Maybe 10 or more. It then started to drop out and ramp up.
I wonder if some sort of self protection is going on.
My gen set has voltage regulation and I have it set at 230V and it is stable at that. The Hz is a little high at 53. Thogh both these were from the pip display. I will check when I have time with the fluke and also adjust the gen set speed to get the Hz correct. Based on your experience I doubt it will change things though. Is your unit from MPP Solar? What firmware version?

No I haven't tried a non generator input to charge from the PIP.

Yes my unit is a MPP solar branded with the latest lithium firmware upgrade.

No I don't have mains power at home (offgrid) Though I do have a 6000w continuous inverter that powers 240v AC to my home.

Along with a 2nd 48v lithium battery bank (just to ensure isolation with two separate systems). So as mentioned before running the PIP powered from a 15A outlet in my house and having it DC charge the 2nd 48v lithium battery should simulate as good or better quality power than mains power and eliminate the generator as the issue.

I will test this over the next few days and report back.

[andys]

Lately my mains input has been higher, around 245-250V. I have been successfully charging at 40A with no drop-outs.

Feels like it might have a "hair trigger" on change in input voltage or phase which makes it stop charging suddenly when on lower voltages or generator.

[Ian60D]

I'll try adjusting the voltage on mine tomorrow. Haven't had a chance to set the frequency correctly yet either.
I tried charging with 2 units but the second unit won't charge at all. I tries and drops out immediately and then beeps. I just received my parallel kits so will install those and try again.

[paulvk]

Is your mains input set to UPS or Appliance ?