PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

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.
User avatar
rthorntn
Groupie
Posts: 47
Joined: Sat, 06 Jun 2020, 08:36

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by rthorntn »

coulomb wrote: Tue, 21 Jul 2020, 19:41 I'm pretty sure the only way is to set the back to grid and back to battery voltage settings very low (so they never cause a mode change), and use the output source priority (setting 01 or there is the POP command to set it) to change from utility-first priority (POP00) to battery-first priority (POP02).
Thanks Coulomb, yuck, back to grid lowest is 44v and back to battery lowest is 48v, it would be great if you could just disable them completely.
4.2KW solar
Two MPP 5048MG inverters
15.36KWH battery (8 x Zenaji Aeon LTO)
dRdoS7
Groupie
Posts: 91
Joined: Fri, 28 Sep 2018, 12:28

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by dRdoS7 »

Hi,
rthorntn wrote: Tue, 21 Jul 2020, 14:56 Is anyone using a Victron BMV with these inverters, it uses a shunt right (up to 6000A/50mV shunt, that seems huge, the 500A/50mV would surely be alright for most people) so it has very accurate measurements and doesn't suffer from the voltage decreasing by nearly a volt when load is applied to the batteries?

I assume these things "learn" the SOC "curve" because they know how the current used changes the voltage over time or something like that?

With the Victron BMV, can its measurements be used to override the inverter measurements, so the inverter switches back and forth between batter and utility based on the BMV voltage?
I doubt the BMV learns anything, it maybe called Smart, but not that smart.

It knows the Amps and Voltage, and would calculate the Ah. You set the battery capacity at setup, and the parameters for the BMV to call the SOC to be 100%.

If you want to control the inverter, you should set it to Utility, and use a voltage controller to switch the mains input. Cheapest method.

I used that method with my first inverter.

If you already have a BMV, you can use that to control the mains input.

Only problem there would be an error which causes the inverter to go into bypass mode. That would require a sensing wire on the inverter output so that if the output drops, it prevents the input from being switched off, or switches it back on. Easy enough to do with a contactor. I have done similar with my MG, but use it to operate a bypass when an inverter error causes it to switch it's output off (i.e. error #08).

dRdoS7
ojeysky
Groupie
Posts: 53
Joined: Mon, 01 Jul 2019, 03:06
Location: Nigeria

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by ojeysky »

coulomb wrote: Thu, 09 Jul 2020, 21:44
ojeysky wrote: Thu, 09 Jul 2020, 20:55 Mine reads 41.14 yet the early float bug still exists
Ok, so firmware version 20.59 would be no use to you. Until that firmware update file becomes available, there is nothing I can do.

Edit: 20.59 is a firmware that works on 5 different variants, some 48 V variants and some 24 V variants. I suspect that with the lithium BMS integration, one firmware no longer covers both the 48 V model(s) and the 24 V models. For example, your screen doesn't mention an MCU/display/BMS firmware, which I believe the 48 V equivalent would.

If so, that means it might take a while.
So I have been observing the firmware that came with my replacement Board, while the early float bug still exists, it seem it no longer have impact on the charge rates as my batteries still charges at the highest possible current that it was doing when in bulk mode. I think there may have been a slight improvement in the latest firmwares
pierre.
Noobie
Posts: 2
Joined: Wed, 29 Jul 2020, 06:59

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by pierre. »

rddkrn wrote: Sat, 14 Mar 2020, 17:53 Today I paralleled my two inverters. All works well except for unstable ac output voltage. The voltage changes from around 220V to 235V (for 230V setup) which is read on the LCD display. This caused the lights in my house flickering.
I have exactly the same problem. When the power generated by solar PV is the same as the load the output voltage become unstable. See this topic and video:

https://powerforum.co.za/topic/6326-axp ... ment-78670
https://www.youtube.com/watch?v=Rh4GEBk2sJk

Have you found a solution to the problem? How high is your PV voltage? This problem only seems to happen with the Voltronics inverters that have a MPPT rating of 450V. I have 9x 340w panels per string, so my PV voltage is just below 400v.
JaseZA
Noobie
Posts: 3
Joined: Tue, 09 Jun 2020, 03:41

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by JaseZA »

ojeysky wrote: Thu, 02 Jul 2020, 17:14
We have similar set-up, mine is the 3024GK, and I also just got a ANT BMS, can you share how you are logging the BMS data? Do you have the float bug on yours as well? which causes the inverter not to get past the float voltage and what's your float/bulk settings?
Sorry, missed the notification for this query - mine has the premature float bug - I work around it by setting bulk and float the same and stopping charging at 95% using Home Assistant.

Communication from the Ant-bms is handled via bluetooth to my RaspberryPi through some custom python code I compiled from various sources. Let me know if you're still looking for a solution, I can send you what I've done.
JaseZA
Noobie
Posts: 3
Joined: Tue, 09 Jun 2020, 03:41

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by JaseZA »

Just wondering if anyone else has encountered an overload fault with their 3kw or 5kw model. Basically it won't bypass to grid when battery overload happens in the 105%-130% rated power band. It will bypass to grid when overload >130%. Instead of bypassing to grid, it just shuts down the output and triggers fault 07 (Overload error). This seems like a firmware issue.

I've got more info on this here: https://powerforum.co.za/topic/6537-vol ... ss-glitch/

Also, would love some patched firmware @Coulomb! :D
dRdoS7
Groupie
Posts: 91
Joined: Fri, 28 Sep 2018, 12:28

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by dRdoS7 »

Hi,

I was planning to buy a Daly Smart BMS, but read in a forum that it requires the connected inverter to "pre-charge". Never heard this term before. It sounds like a soft start from reading Wiki. Does the 5048MG have this function?

Apparently, it causes the (maybe not so) Smart BMS to cycle On and Off if there is no pre-charge.

Other BMSs may also require this.

Thanks,

dRdoS7
dRdoS7
Groupie
Posts: 91
Joined: Fri, 28 Sep 2018, 12:28

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by dRdoS7 »

Hi,
JaseZA wrote: Mon, 03 Aug 2020, 00:02 Just wondering if anyone else has encountered an overload fault with their 3kw or 5kw model. Basically it won't bypass to grid when battery overload happens in the 105%-130% rated power band. It will bypass to grid when overload >130%. Instead of bypassing to grid, it just shuts down the output and triggers fault 07 (Overload error). This seems like a firmware issue.

I've got more info on this here: https://powerforum.co.za/topic/6537-vol ... ss-glitch/

Also, would love some patched firmware @Coulomb! :D
My 5048MG has had errors which causes it to shut it down rather than going to bypass. It was very annoying! I made an inverter bypass with a relay. I had to replace it after about a year, replaced with same model. I think I need to put a larger one in. Anyway, now it can do what it likes, I'll still have power, if the grid isn't down.

Another plus is that if I do need to do some work on or around the inverter or batteries, I can bypass it without power loss. It's either that, or operate the 3 changeover switches really fast!

dRdoS7
User avatar
coulomb
Site Admin
Posts: 4319
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by coulomb »

dRdoS7 wrote: Mon, 03 Aug 2020, 11:27 it requires the connected inverter to "pre-charge". Never heard this term before. It sounds like a soft start from reading Wiki. Does the 5048MG have this function?
Pre-charge isn't something that is commonly implemented in inverters, and certainly PIPs/Axperts don't have it. But all inverter installations should have it.

Inverters have large capacitors across the battery terminals to keep the voltage stable over the span of micro- and milli-seconds. A discharged capacitor looks like a dead short, and the capacitors can draw thousands of amps briefly if a battery is connected across them suddenly. This sudden high surge of current is bad for the capacitors and possibly other parts of the inverter, and for whatever makes the connection. If it's a cable lug contacting a terminal, it can blow a chunk out of that lug or terminal, reducing its ability to pass operating current (up to a hundred amps or so). If it's a fuse casing making contact with its electrical contacts, it can burn a scorch mark in the metal part of the fuse and/or its contact, again reducing its ability to continuously pass large currents.

Electric cars have the same problem, only magnified by the typically much higher voltage of the EV battery. That's why when an EV becomes "ready", you can hear a series of muted clicks as buried contactors come on and off rapidly, performing (among other things) their pre-charge.

Pre-charge is usually achieved by initially connecting the battery to the inverter via a specially designed resistor. That resistor limits the current to typically a few tens of amps; still enough to clean contacts, but not enough to damage them. After a suitable period of time, typically a few tenths of a second to a few seconds, the resistor is bypassed by a contactor or switch, and that contactor or switch carries the full current of the operating inverter.

It's highly desirable that it's not possible for the inverter to start drawing significant current while the resistor is still in circuit. The resistor is designed to withstand a pulse of power, often as high as 25 times its continuous power rating. If it's forced to dissipate anything like its peak power for more than a second or so, it will likely explode. Some EV converters have had that experience :oops:

A pre-charge circuit could be as simple as a suitable resistor wired across the battery isolator. But then the inverter has battery voltage all the time, not allowing for maintenance, and there is too much chance that the inverter will wake up and draw power while the isolator is "off". So it's usually necessary to have two battery isolators, so the inverter can be turned off properly. One of those isolators could also be protection, e.g. a removable fuse or possibly a large DC rated breaker.

The BMS that comes with a packaged lithium battery typically contains high power MOSFETs that can be wired to provide a current limiting function. My understanding is that these provide a sort of natural pre-charge function, although they may limit the initial current surge to something like normal operating current or a little higher. But they also have a soft "off switch" that disconnects the MOSFETs completely. So they allow for complete isolation, splat-free connecting of fuses and lugs, and automatic pre-charge.

A stand alone BMS that might be controlling a wide range of actual battery cells usually won't have those MOSFETs installed, because the operating current of the battery isn't known in advance, and to include MOSFETs large enough to handle the largest possible battery would be prohibitively expensive. That sounds like what you have, dRdoS7, so they're in effect saying that you have to provide the pre-charge circuit yourself. As to why it might connect and disconnect continuously, I'm not sure. It likely has a current sensor, so perhaps in the absence of pre-charge, it would treat the capacitor in-rush current as an overload, and perhaps disconnect somehow, removing the overload, and the cycle repeats.

Edit: or perhaps they're saying that with certain batteries, the internal resistance of the battery might be high enough to cause the battery voltage to collapse under the overload, and not start the inverter. This on its own might cause the cycle of connecting and disconnecting described. Old engineers like myself may be reminded of a thing called "motorboating" in radio circuits. But with the size of battery used with house sized inverters, this is not likely to be an issue.
Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
1.4 kW solar with 1.2 kW Latronics inverter and FIT.
160 W solar, 2.5 kWh 24 V battery for lights.
Patching PIP-4048/5048 inverter-chargers.
dRdoS7
Groupie
Posts: 91
Joined: Fri, 28 Sep 2018, 12:28

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by dRdoS7 »

Hi,
coulomb wrote: Tue, 04 Aug 2020, 07:53
dRdoS7 wrote: Mon, 03 Aug 2020, 11:27 it requires the connected inverter to "pre-charge". Never heard this term before. It sounds like a soft start from reading Wiki. Does the 5048MG have this function?
Pre-charge isn't something that is commonly implemented in inverters, and certainly PIPs/Axperts don't have it. But all inverter installations should have it.
So, the 5048MG don't have it. Makes it easy.
A stand alone BMS that might be controlling a wide range of actual battery cells usually won't have those MOSFETs installed, because the operating current of the battery isn't known in advance, and to include MOSFETs large enough to handle the largest possible battery would be prohibitively expensive. That sounds like what you have, dRdoS7, so they're in effect saying that you have to provide the pre-charge circuit yourself. As to why it might connect and disconnect continuously, I'm not sure. It likely has a current sensor, so perhaps in the absence of pre-charge, it would treat the capacitor in-rush current as an overload, and perhaps disconnect somehow, removing the overload, and the cycle repeats.

Edit: or perhaps they're saying that with certain batteries, the internal resistance of the battery might be high enough to cause the battery voltage to collapse under the overload, and not start the inverter. This on its own might cause the cycle of connecting and disconnecting described. Old engineers like myself may be reminded of a thing called "motorboating" in radio circuits. But with the size of battery used with house sized inverters, this is not likely to be an issue.
There's another use for the term "motorboating", nothing to do with water or electronics, but which makes me smile. :shock:

I don't have a BMS, yet, just browsing, as they say. I am buying 16 cells from Leonford, when we return home mid August. Though current state of affairs in Vic. makes that less likely by the day!

This from the owner of one of these BMSs:
I've put my BMS to the side and requested my money back.

It doesn't work!
when it goes into protection mode (I triggered it), the whole pre-charge thing needs to be done again with my inverter.

That makes it for me an useless product.

Inverters that doesn't need pre-charge can work just fine.
Or if you don't mind to manually boot up the whole thing again, it's fine also.
Another owner appears to have the same On/Off problem. A device such as you described is also mentioned. Sounds too much trouble. An extra bit to fail? I suppose that describes the BMS too.

I think I'll look for something, not quite so "smart" then. They have a low balance charge, so I'd have buy a separate balancer. Just though it might be handy to see what's doing, and be able to change settings, rather than one that has settings locked in, and no monitoring.

Thanks,

dRdoS7
jannie
Noobie
Posts: 10
Joined: Wed, 25 Mar 2020, 05:57
Real Name: Jan Hough

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by jannie »

dRdoS7 wrote: Wed, 01 Apr 2020, 17:18
data wrote: Thank you for your reply. How did you get that email? What software are you using??
I use the supplied software, Watchpower.
coulomb wrote:
dRdoS7 wrote: Wed, 01 Apr 2020, 17:18 My PIP5048MG did similar a couple of days ago. It had a peak 6.0KW load while running off solar/batteries, and went to Line Mode, but it didn't go back to Battery Mode after the load dropped. No fault indication on the local panel.
Did you wait 10 minutes? Unpatched firmware forces the inverter to stay in line/bypass mode once it gets there for a minimum of 10 minutes (2 minutes for patched firmware).
No, when I received the email, I went to the garage to check. I saw it was in bypass, but no longer had a high load, so I switched it off & on. If it happens again, I'll wait. I had a look in the manual, but there was no mention of any time for a return. You'd think something like that would warrant a mention.

Thanks,

dRdoS7.

OK, after struggling a bit to get the email functionality working on WatchPower I finally got it right.
Gmail will not work with the standard safety Google account settings and 2 Factor Authorisation (which you should implement!).
These are the settings for a hotmail account.

[ Edited Coulomb: attempted to repair quoting ]
Attachments
WatchPower email.jpg
WatchPower email.jpg (64.26 KiB) Viewed 1178 times
User avatar
rthorntn
Groupie
Posts: 47
Joined: Sat, 06 Jun 2020, 08:36

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by rthorntn »

tl;dr would it be ideal for me to get a BMV and hack the inverters so I can set my back to grid and back to battery voltage settings real low (how low) and control switching between battery and grid with MQTT?
rthorntn wrote: Wed, 22 Jul 2020, 06:11
coulomb wrote: Tue, 21 Jul 2020, 19:41 I'm pretty sure the only way is to set the back to grid and back to battery voltage settings very low (so they never cause a mode change), and use the output source priority (setting 01 or there is the POP command to set it) to change from utility-first priority (POP00) to battery-first priority (POP02).
Thanks Coulomb, yuck, back to grid lowest is 44v and back to battery lowest is 48v, it would be great if you could just disable them completely.
I'm not happy with my inverters voltage or SoC measurement accuracy, I'm pretty sure I'm going to get a Victron BMV.

Lol, the intricacies of my pick 'n' mix home storage make my brain hurt.

So say I have a BMV and I have much better accuracy for voltage and SoC. To me it then makes sense to use voltage I get from the BMV to make decisions, so assume that I use ICC and MQTT publish from Home Assistant, which one of these (I think the 1st):

Code: Select all

Inverter/SetMode to 0 for Grid, 1 for SUB, 2 for battery (SBU)

or

Inverter/Axpert/ChargePriority to 0 Utility first, 1 Solar first, 2 Solar and Utility, 3 Solar Only
OK, so say I figure out the MQTT command, I still have the elephant in the room that the SetBackToDischarge and SetBackToGrid minimums are too high for my LTO chemistry. (which can also be set through MQTT Inverter/Axpert/SetBackToDischarge_Volts & Inverter/Axpert/SetBackToGrid_Volts).

Unless I'm missing something the BMV will just give me a nice accurate reading, I can't act on it, when we talk about setting the back to grid and back to battery voltage settings very low, what are we talking here (my LTO range is 42.5v to 55.5v) on the standard firmware the lowest I can set back to grid is 44v and back to battery is 48v. In my case if it was possible are we talking about setting both the back to grid and back to battery voltage to 42v?
dRdoS7 wrote: Wed, 22 Jul 2020, 08:16use a voltage controller to switch the mains input
Thanks, but I don't know what this means, do you mean just remotely switching off the grid connection to the inverters with a big relay, I don't think I like that idea and it's definitely not something I would be doing myself?

I keep reading about the float bug, fixed in the patched firmwares, I can't work out if it's an issue for me?

The PIP-4048MS and PIP-5048MS inverters thread has a convo between Wulfee, Coulomb and Weber around patched firmware that improves the SoC accuracy, is that something that these inverters also suffer from?
[Wulfee]

So does the LC flavour give a more realistic battery % indicator for Lithium Ion batteries on the front display?

[Coulomb]

[ Edit: As Weber points out in the post after next, I had quite forgotten an improvement that I suspect he suggested and largely implemented in the fully patched firmwares. So the following paragraph and short answer are quite wrong. ]

Marginally, in that the wild guess is a load compensated wild guess. The guessed SOC in percent is still basically the number of tenths of a volt above the DC low cutoff setting (setting 29) minus 2%. You might be able to find a value for setting 29 that provides an acceptable indication. Non-LFP lithium ion batteries tend to range in cell voltage from about 3.6 to nearly 4.2 VPC, so that's about 0.6 VPC. For a typical 14S battery, that's about an 8.4 V range. The firmware assumes about 9.5 V (for 0% to 95%), so that's about a 10% scale error, or just over.

[weber]

Coulomb is quite mistaken here. Our patched firmware gives a much more realistic battery SoC indicator on the front display, for cobalt-blend lithium ion batteries. Our SoC figure is not calculated in the way that Coulomb claims. Instead it treats the Float voltage setting as 100% and the Low Voltage Cutoff setting as 0% and scales the SoC proportionally in between, based on the load-compensated battery voltage.

Estimated_SoC = 100% × (Vbat_comp - Vcutoff) / (Vfloat - Vcutoff)

Of course it's nowhere near as good as a coulomb counter. It's maybe ±10%, assuming you have set the float and cutoff voltages correctly, and you have set the strength of load compensation ("kettle" compensation) correctly, as described in the AussieView™ and KettleKomp™ manual.
I looked at the manual, is KettleKomp™ available on these inverters?

I think I have seen my voltage jump around when the wife switches the kettle on. Does that happen with a BMV?

Thanks everyone!

Cheers
Richard
4.2KW solar
Two MPP 5048MG inverters
15.36KWH battery (8 x Zenaji Aeon LTO)
dRdoS7
Groupie
Posts: 91
Joined: Fri, 28 Sep 2018, 12:28

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by dRdoS7 »

rthorntn wrote: Mon, 10 Aug 2020, 13:58
dRdoS7 wrote: Wed, 22 Jul 2020, 08:16use a voltage controller to switch the mains input
Thanks, but I don't know what this means, do you mean just remotely switching off the grid connection to the inverters with a big relay, I don't think I like that idea and it's definitely not something I would be doing myself?
It doesn't require a big relay. It wouldn't be remote, put a contactor in the input cable to the inverter. What sort of AC load is the maximum? Single or 3 phase? 63A contactor/s controlled by the BMV wouldn't be difficult to wire up.

dRdoS7
User avatar
rthorntn
Groupie
Posts: 47
Joined: Sat, 06 Jun 2020, 08:36

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by rthorntn »

dRdoS7 wrote: Mon, 10 Aug 2020, 15:12
rthorntn wrote: Mon, 10 Aug 2020, 13:58
dRdoS7 wrote: Wed, 22 Jul 2020, 08:16use a voltage controller to switch the mains input
Thanks, but I don't know what this means, do you mean just remotely switching off the grid connection to the inverters with a big relay, I don't think I like that idea and it's definitely not something I would be doing myself?
It doesn't require a big relay. It wouldn't be remote, put a contactor in the input cable to the inverter. What sort of AC load is the maximum? Single or 3 phase? 63A contactor/s controlled by the BMV wouldn't be difficult to wire up.

dRdoS7
Thanks, single phase, do you have an example of the contactor?
Last edited by rthorntn on Tue, 11 Aug 2020, 12:16, edited 1 time in total.
4.2KW solar
Two MPP 5048MG inverters
15.36KWH battery (8 x Zenaji Aeon LTO)
dRdoS7
Groupie
Posts: 91
Joined: Fri, 28 Sep 2018, 12:28

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by dRdoS7 »

rthorntn wrote: Tue, 11 Aug 2020, 10:47
dRdoS7 wrote: Mon, 10 Aug 2020, 15:12
rthorntn wrote: Mon, 10 Aug 2020, 13:58

Thanks, but I don't know what this means, do you mean just remotely switching off the grid connection to the inverters with a big relay, I don't think I like that idea and it's definitely not something I would be doing myself?
It doesn't require a big relay. It wouldn't be remote, put a contactor in the input cable to the inverter. What sort of AC load is the maximum? Single or 3 phase? 63A contactor/s controlled by the BMV wouldn't be difficult to wire up.

dRdoS7
Thanks, single phase, do you have an example of the contractor?
This is what I will use:

https://agmelectrical.com.au/contactors ... ed-en.html

I need 2 NC & 2 NO, you probably would be able to use a 1-pole NC, l but I don't see one on this site. There are 40A 2-pole, but they're the same price anyway. Also, it's a 240V coil, which is fine for my inverter bypass, but you would then need an intermediate 240V relay with a 12V coil, which the BMV can control. I used that method to switch my old inverter input off previously. With that I used a 25A DPDT relay, but I've had a couple of those fail over the years. I use one in my existing bypass, so I'm buying a 63A contactor to replace it. After the second one failed, I found the specs, and it's 25A make, but only 10A break, IIRC (or vice versa). :roll: Pays to read specs first!

dRdoS7
User avatar
rthorntn
Groupie
Posts: 47
Joined: Sat, 06 Jun 2020, 08:36

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by rthorntn »

dRdoS7 wrote: Tue, 11 Aug 2020, 11:45
rthorntn wrote: Tue, 11 Aug 2020, 10:47
dRdoS7 wrote: Mon, 10 Aug 2020, 15:12 It doesn't require a big relay. It wouldn't be remote, put a contactor in the input cable to the inverter. What sort of AC load is the maximum? Single or 3 phase? 63A contactor/s controlled by the BMV wouldn't be difficult to wire up.

dRdoS7
Thanks, single phase, do you have an example of the contractor?
https://agmelectrical.com.au/contactors ... ed-en.html
Thanks.
4.2KW solar
Two MPP 5048MG inverters
15.36KWH battery (8 x Zenaji Aeon LTO)
Shuntmunted
Noobie
Posts: 7
Joined: Tue, 24 Dec 2019, 12:16
Real Name: Ben Moloney

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by Shuntmunted »

Hey Guys,

I have the PIP 5048 MG system and it was working fine except for, why appeared to be, the float bug which was capping my batteries at 54v. I updated the firmware with 71.80a and now the unit has developed this strange behaviour when the inverter is running. See video below:

https://youtu.be/O2c2zPfwCm8

The unit works fine when the inverter is off and charges no problem:

https://youtu.be/jJm9JKIDk60

Here are the settings:

https://youtu.be/jcTG8GN-dcs

I patched it as per the instructions and the screen shows 71.80a. It looks to have fixed the float bug but now I have a more debilitating issue. Any help would be greatly appreciated. We will be living off grid in just a few weeks 😬

Thanks,

Ben(Aus)
4.2kw Solar (12x 360w Canadian Solar)
PIP5048MG inverter
20kWh of LifePO4 Aliexpress Cells
ZEVA BMS16s 200a Shunt and 400a Gigavac contactor
User avatar
coulomb
Site Admin
Posts: 4319
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by coulomb »



@Shuntmunted, I notice that your charge LED is flashing quicky, and possibly erratically, when the PV power is erratic. When you turn the loads off, the PV stabilises, but also the charge LED starts flashing slowly (as normal).

Can you please keep an eye on that LED, to see if it always correlates with the erratic PV charging? If it does correlate, that might save time with checking whether other firmwares cause this issue.
Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
1.4 kW solar with 1.2 kW Latronics inverter and FIT.
160 W solar, 2.5 kWh 24 V battery for lights.
Patching PIP-4048/5048 inverter-chargers.
Shuntmunted
Noobie
Posts: 7
Joined: Tue, 24 Dec 2019, 12:16
Real Name: Ben Moloney

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by Shuntmunted »

@coulomb thanks for the reply. I am only getting erratic P.V. Charging when I have a load. Even when I disconnect all the loads yet have the inverter running I get erratic P.V. charging. Even the output voltage fluctuates between 229-231v. If I turn the inverter off and just have the P.V. charging the batteries all is fine and the P.V. stabilises. If I shut off the P.V. feed and run the inverter off the batteries it’s fine and the output power is stable.
4.2kw Solar (12x 360w Canadian Solar)
PIP5048MG inverter
20kWh of LifePO4 Aliexpress Cells
ZEVA BMS16s 200a Shunt and 400a Gigavac contactor
Shuntmunted
Noobie
Posts: 7
Joined: Tue, 24 Dec 2019, 12:16
Real Name: Ben Moloney

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by Shuntmunted »

Shuntmunted wrote: Fri, 14 Aug 2020, 07:49 Hey Guys,

I have the PIP 5048 MG system and it was working fine except for, why appeared to be, the float bug which was capping my batteries at 54v. I updated the firmware with 71.80a and now the unit has developed this strange behaviour when the inverter is running. See video below:

https://youtu.be/O2c2zPfwCm8

The unit works fine when the inverter is off and charges no problem:

https://youtu.be/jJm9JKIDk60

Here are the settings:

https://youtu.be/jcTG8GN-dcs

I patched it as per the instructions and the screen shows 71.80a. It looks to have fixed the float bug but now I have a more debilitating issue. Any help would be greatly appreciated. We will be living off grid in just a few weeks 😬

Thanks,

Ben(Aus)

Plot twist, I changed the firmware back to 71.70 and the PV fluctuations persist. I put a 1kW load on the system and the PV stabilises as per that load however, it still fluctuates a bit. It appears to be the current going from the PV to charge the batteries that is erratic. PV to load is smooth and consistent.

Also, the batteries are at 53.3v and the Unit has them at 100% (no charge LED) when the bulk charge is set at 55.2 and float is 53.8v.

@coulomb any idea what would cause PV charge to be erratic but PV to load to be normal?
4.2kw Solar (12x 360w Canadian Solar)
PIP5048MG inverter
20kWh of LifePO4 Aliexpress Cells
ZEVA BMS16s 200a Shunt and 400a Gigavac contactor
User avatar
coulomb
Site Admin
Posts: 4319
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by coulomb »

Shuntmunted wrote: Sat, 15 Aug 2020, 09:02 Plot twist, I changed the firmware back to 71.70 and the PV fluctuations persist.
I wondered if that might be the case.
any idea what would cause PV charge to be erratic but PV to load to be normal?
Models with the 450 V max (or 500 V max) SCC charge the battery through a circuitous route: PV voltage is first boosted to 350-450 V (the "DC bus"). The bus has varying loads on it from the "inverter proper" (the DC to AC converter powering the loads). There is a control system for the DC bus voltage that has to cope with the varying loads and the varying PV available power. Next, there is a buck stage that operates only when the battery is charging from either PV or utility or both (only when the battery is charging from utility for 145 V max PV models). This reduced bus voltage is then converted down to battery voltage by the DC-DC converter. There is a control system for the battery charge current.

So there are three converters involved (a boost, a buck, and a bidirectional converter), and at least two control systems (one for the DC bus voltage and PV charge power, and the other for the battery charge power via the bucked DC bus voltage). The control system for keeping the AC output voltage steady will also be affecting the DC bus voltage.

At times, power flow through the bidirectional DC-DC converter may be charging direction, i.e. the battery may have net charge one moment, and net discharge the next. Batteries have hysteresis; their terminal voltage changes depending on the direction of current flow. There are almost certainly asymmetries with the DC-DC converter as well. I suspect that the control systems have a hard time coping with all the fluctuations coupled with the changing dynamics when the battery power flow reverses direction. If average load power is about the same as average PV power, but both are fluctuating, then the power flow reverses will be frequent. I suspect that this is what's behind the erratic PV power.

The buck converter is a single directional converter; it can't act as a boost converter when the power flow is in the "wrong" direction (away from the battery). It can however be "switched off", which is really turning it on and not pulsing it (turning it into a near short circuit). Every time the battery power flow reverses, the buck converter may have to be reconfigured from a true buck converter to a short circuit and back again. It's not clear to me whether this involves a lot of work for the firmware, and whether this may contribute to the erratic PV power or not.

I have a long held theory, sadly still not proven, that the various control systems in the Voltronic inverters suffer from a thing called integral windup. This makes them prone to overshoot, which then has to be corrected, and sometimes that correction can lead to an overshoot in the other direction, and so on. If that's the case, then at least part of the erratic behaviour could be corrected or considerably improved by firmware alone, at least in theory.
Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
1.4 kW solar with 1.2 kW Latronics inverter and FIT.
160 W solar, 2.5 kWh 24 V battery for lights.
Patching PIP-4048/5048 inverter-chargers.
pierre.
Noobie
Posts: 2
Joined: Wed, 29 Jul 2020, 06:59

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by pierre. »

Shuntmunted wrote: Sat, 15 Aug 2020, 09:02
Plot twist, I changed the firmware back to 71.70 and the PV fluctuations persist. I put a 1kW load on the system and the PV stabilises as per that load however, it still fluctuates a bit. It appears to be the current going from the PV to charge the batteries that is erratic. PV to load is smooth and consistent.
Check the following: is the PV erratic only when the load is almost the same as the PV generation? As an example, if you are getting stable 1kW PV does this problem perhaps only appear when the load is between 700W and 1300W? If so you are probably facing a similar issue to what I faced. Two things you can try:
1) Check if disabling the solar balance feature reduces the problem. On mine this is setting 31.
2) Check if firmware version 71.82 reduces the problem: https://powerforum.co.za/topic/6620-axp ... ugust-2020

FYI: I think output voltage fluctuating between 229 and 231 is normal. Even on Victron inverters introducing a load to the battery drops the output voltage: https://www.youtube.com/watch?v=ubOaxu_2i9s
In your case I think the PV voltage dropping causes load on the battery which drops the voltage for a moment.
Shuntmunted
Noobie
Posts: 7
Joined: Tue, 24 Dec 2019, 12:16
Real Name: Ben Moloney

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by Shuntmunted »

@pierre. thanks for the reply!

Have a look at the data log https://www.dropbox.com/s/ksne4v8cpar9a ... g.xls?dl=0
The data log describes the issue better than I can in words. You can see that when there is a load on the AC side of the system the PV starts playing up.

Thanks for your suggestions, I will check setting 31 and give the 71.82 firmware a go.

Many thanks,

Ben
4.2kw Solar (12x 360w Canadian Solar)
PIP5048MG inverter
20kWh of LifePO4 Aliexpress Cells
ZEVA BMS16s 200a Shunt and 400a Gigavac contactor
Shuntmunted
Noobie
Posts: 7
Joined: Tue, 24 Dec 2019, 12:16
Real Name: Ben Moloney

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by Shuntmunted »

@pierre. I tried 71.82 and disabled 31..... no change 😭
4.2kw Solar (12x 360w Canadian Solar)
PIP5048MG inverter
20kWh of LifePO4 Aliexpress Cells
ZEVA BMS16s 200a Shunt and 400a Gigavac contactor
gazzaman2k
Noobie
Posts: 3
Joined: Sun, 26 Apr 2020, 17:44
Real Name: Gareth

Re: PIP-5048GE, PIP-5048GK and PIP-5048MG inverters (with unsafe SCC)

Post by gazzaman2k »

Shuntmunted wrote: Fri, 14 Aug 2020, 07:49 Hey Guys,

I have the PIP 5048 MG system and it was working fine except for, why appeared to be, the float bug which was capping my batteries at 54v. I updated the firmware with 71.80a and now the unit has developed this strange behaviour when the inverter is running. See video below:

https://youtu.be/O2c2zPfwCm8

The unit works fine when the inverter is off and charges no problem:

https://youtu.be/jJm9JKIDk60

Here are the settings:

https://youtu.be/jcTG8GN-dcs

I patched it as per the instructions and the screen shows 71.80a. It looks to have fixed the float bug but now I have a more debilitating issue. Any help would be greatly appreciated. We will be living off grid in just a few weeks 😬

Thanks,

Ben(Aus)
i take it you have 4 solar panels on the system? mine done that exact same thing, stick 5 panels on whats happeing is the mppt is going below the 120v cuttoff and then its resetting,
Post Reply