PIP-4048MS and PIP-5048MS inverters

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Post by dockarl » Sun, 26 Jul 2015, 20:29

Yep Solamahn I suspect it's ripple the charge controllers are trying to chase, and that's what Eric implied also. If my understanding of ripple is correct more batts = more 'capacitance' = batts filter the ripple. It still highlights a problem - better to deal with the ripple at the inverter and charge controller than at the batteries. Some research I have found indicates that high ripple aint good for batteries lifespan, but anecdotal evidence suggest more batts does seem to help the issue with these units. I guess it comes down to the economics of buying a decent charge controller vs the economics of lost lifespan from batteries due to potential unseen overvolts and high ripple.. In my case I was able to find a good european brand SCC for about the same cost as the money I wasted on the pcm5048's so it became a pretty easy decision..

In my case I have 12x125Ahr batts, for a 375ahr @ 48 Volts which isn't all that small, really. I think from memory MPP's specs call for minimum 200Ahr battery so per specs I have almost double the requirement and should be fine but doesn't seem to be the case.

Glad to hear your 4048ms system is working great.

Coulomb - thankyou very much for spending that time with Weber on your 'project day' - much appreciated. One thing I would like to do in part recompense is to donate the 'other' board to you guys to use for protocol research or maybe as a cold spare for all of us..

Cheers from Alice Springs,

M
Last edited by dockarl on Sun, 26 Jul 2015, 11:26, edited 1 time in total.

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Post by solamahn » Sun, 26 Jul 2015, 21:35

Yes. You notice that when AGM's are full, they don't regulate voltage as good. But that could be said of all battery chemistries, I think. I wonder if setting the float to 52 would help. But really the scc should react quick enough to a change in solar current so that it is not the batteries that at doing the voltage regulation.
I tried lots of different things to fix this problem. Originally I thought the MOSFET failures were due to overheating so I mounted the inverters off the wall a bit, turned the fans upside down, reduced max solar charge, reduced load, fitted smaller ac out breakers, connected panels 3 in series instead of 2 and even changed from using one inverter to two in parallel.
Looks like the problem was always the use of 125A fets on hs1 instead of the 200A ones which are fitted on the latest versions.
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Post by ChrisHobson » Mon, 27 Jul 2015, 08:34

solamahn wrote:
Looks like the problem was always the use of 125A fets on hs1 instead of the 200A ones which are fitted on the latest versions.


Hi Solamahn

When did they make the change from 125A to 200A mosfets roughly?

Chris

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Post by solamahn » Mon, 27 Jul 2015, 10:18

I don't know. It must have been this year some time. Hopefully yours has the 200's
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Post by weber » Tue, 04 Aug 2015, 05:49

Thanks to gmacd33 I just learned what Giant Power have done to the IPS-4000WM to get it listed as meeting IEC 62109 on the Australian Clean Energy Council website.

Nothing.

They have written an Application Note that contains the following advice:

------------------------
The Giant Power IPS4000WM is a standalone offgrid inverter and is certified as IEC62109-1 & IEC62109-2 complaint as required by section 4.3.11. The IPS4000WM has a MPPT voltage range of 60-115v and as such is classified as ELV under AS5033:2014 so sections 3.4 Protection against Earth Faults do not apply providing the voltage is kept within this range.
------------------------

The truth is, a PV array is not classified as ELV based on its MPP voltage, but its open circuit voltage (at the lowest expected operating temperature). That maximum open circuit voltage has to be less than 120 V for it to be ELV. The IPS-4000WM (PIP-4048MS) can take open circuit voltages up to 145 V.

That means our our choice now for the PIP, in Australia, is probably only strings of two 72-cell modules (144 cells). You might just be able to use strings of three 54-cell modules (162 cells) depending on your minimum dawn temperature and their exact voltage rating and temperature coefficient. But there is no number of 60-cell modules that will work. Two would have their max power point below 60 V when hot, and three would have their open circuit voltage above 120 V when cold.

We can no longer use strings of three 60-cell modules, or three 72-cell modules as I did on Black Monolith #1.
Last edited by weber on Mon, 03 Aug 2015, 23:28, edited 1 time in total.
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Post by offgridQLD » Wed, 05 Aug 2015, 01:04

So what happens if you have freak cold day is your system illegal that day?

I agree and understand the issue. Just not 100% on what responsibility - accountability for the weather the designer - installer of the system has.

Do you just have to show you have taken reasonable steps based on historical weather data for the area.

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Post by weber » Wed, 05 Aug 2015, 01:47

offgridQLD wrote: So what happens if you have freak cold day is your system illegal that day?
No.
I agree and understand the issue. Just not 100% on what responsibility - accountability for the weather the designer - installer of the system has.
I'd say if it's a generic system, it's up to the designer to specify the lowest dawn temperature for which the array will remain ELV, and up to the installer to check that agrees with BOM data for the area it's being installed in. If it's being designed for a specific location then it's up to the designer to check the BOM data for the general area. It would not be reasonable to expect anyone to precisely account for any local microclimate, just as it would not be reasonable to expect them to exactly predict the future.
Do you just have to show you have taken reasonable steps based on historical weather data for the area.
Yes. In SE Qld, if you're in Brisbane or on the coast, 0°C is a safe figure to use. But it drops as you go inland.
http://www.bom.gov.au/climate/averages/ ... _All.shtml
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Post by Scott » Fri, 14 Aug 2015, 07:37

Not sure if anyone's posted the service manual yet. It's not great but it's something...

http://dealer.mustek.co.za/write/upload ... 31104a.pdf

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Post by Tjadenw » Fri, 14 Aug 2015, 07:48

Thank you

I've been looking for the service manual
Do you have the Axpert 3K service manual also?


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Post by coulomb » Fri, 14 Aug 2015, 16:36

Thanks, Scott, every bit of information helps. This has more detail than the repair manual we had so far.

I hope that this isn't literally the schematic of the MPPT controller:

Image

If so, there is essentially no dead time, so the two MOSFETs will short the panel with the input capacitor in parallel with it, allowing a pulse of current to "shoot through" the pair every half PWM cycle, causing needless heating and stress. But apart from the power supply schematic, which seems fairly complete, these schematics seem very generic. Still, a lot better than nothing.
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.

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Post by coulomb » Tue, 18 Aug 2015, 01:50

At Project Day yesterday, Weber noted that the above topology is somewhat clever; with the interleaved nature of the SCC, there is always a smooth current drawn from the input (when one half is fluxing its inductor (top transistor of the pair on), the other half can be free wheeling (bottom transistor, really just a low loss diode, turned on). Presumably this reduces the current that has to be supplied by the capacitor at the input (this capacitor would absorb solar panel energy when none of the top capacitors are conducting, and supply it later). For those interested in the technical details, here is an article on multi phase buck converters. It looks like ripple current reduction is the main benefit, but there seem to be others.

I spent most of project day installing the parts recently purchased for dockarl's PIP and the spare board he bought. It looks like his original board was one of the first PIPs manufactured, made in 2013. The replacement board is from 2014. It seemed to make sense to work on the 2014 board first. Seven devices went into that board: 2 MOSFETs from the buck stage (and thanks to Scott's manual, we now realise that these aren't in parallel*), 4 IGBTs from the bus end of the DC-DC converter, and the switcher for the bus soft start circuit. This latter one we replaced, even though the originals seemed OK, because the original fault code was 09, "Bus soft start failed". (It was cheap, contrasting with the > $10 each plus tax for the IGBTs). We now believe that when nearly anything blows up from along the power train, the microcontroller will pick this up as a bus soft start error. Weber pointed out that you can't soft start if you have no power, after all.

[ Edit: * Actually, they are in parallel, the manual's block diagram seems to be highly idealised. The MOSFETs or IGBTs for the buck stage are actually in the negative side of the bus, for example. ]
[ Edit: * It turns out that later models have only the one IGBT/MOSFET in the buck stage. These have a TO-220 diode in place of the TO-247 package.]

One of the buck MOSFET/IGBTs (they could be either) is right behind the biggest film capacitor I think I've ever seen. It measures 50 x 40 x 30 mm. When trying to put this MOSFET in, I thought this is nuts, I may as well pull out the capacitor and make things easier for myself.

Image

It's doubly crowded in, by the fins of the heatsink on top and this capacitor in front. Others have the smaller (but still large) blue capacitors in front as well, but fortunately not this one.

Well, it has "leads" that are the same size as the contacts of automotive fuses; they're almost like quick connect terminals. So it was hell getting it out, and even more hell getting the solder out so I could put it back later. Fortunately, there are many plated through holes around the slots where these "leads" pass through the printed circuit board, so I didn't have to worry too much about losing plating between top and bottom side of the board. I ended up using a drill as a crude milling tool, carefully taking my time so that the thin drill didn't break. It did make the MOSFET easier to replace, but for the spare board, I decided not to remove the big black capacitor from that board Image

I set up a current limited power supply, with 24 V of batteries in series, so that hopefully nothing too violent would happen if anything went wrong. I switched on, and... nothing. No light from the LCD display, no fans whirring, no power LED. Huh. I'm sure it was working at least to that level last time, so now with all these repairs it's worse. But wait, last time we were running off the mains, not the battery. Ok, set up the mains wiring, switched on and... nothing. Image

Huh? But last time... Weber pointed out that the mains wire was attached to the other board, the 2013 one, so we must have tested on that board, not this one. But before I did the whole replacement exercise on the other board, I thought I'd try and see what's wrong with this one, if only to figure out what parts to buy. After all, with Scott's manual for the Axpert inverters, the one fairly complete schematic is for the power supply. Well, for the battery power supply; it turns out that there are two similar power supplies, one that runs off the battery, and one that runs from the AC input. They both use a UC3845 "current mode PWM controller" IC, but get this: one is a through-hole version, and one is surface mount! I can only imagine that one came first, say the battery one, and then it was decided that the AC input one would be added later, and they only had room to put it surface mount underneath. I guess they didn't want to mess with the existing through hole one; don't mess with something that works.

All the semiconductors seemed to check out OK, except for the UC3845 chip. The resistances didn't seem close to what the repair manual suggested that they should be. When I checked the other board, the resistances were much closer to what was specified. Resistance checks like these can be very unreliable, since they depend so much on the multimeter used, but I felt confident that the other board would work.

So I mentally noted to buy this chip, and set out to make the repairs to the other (2013) board. It turned out that it wasn't such a hard thing to replace the buck MOSFETs with the big black capacitor still in place, when I managed to squeeze a socket in there and rotated it by a combination of finger power and pliers. So this time, I connected up the power supply and battery, switched on, and... nothing. Waah!   Image

But last time... Ah, again, that was on the mains. Could it be that three of the four power supplies were broken, and the one I hadn't tried was still good? Only one way to find out. I connected the mains wiring, switched on, and... Light! Beautific, glorious light was poring forth from the liquid crystal screen! Joy! Image

Now to connect a battery before I had to head home; it was getting late by this stage. But at that point, I spotted a medium sized white capacitor. Oops! Image I had removed a white capacitor that was blocking the IGBTs (it has normal pigtail leads, so it's easy enough to remove and replace), and had forgotten to replace it. (Part of it is visible at the right end of the photo.) Sigh. So I'd have to wait for Weber to replace the capacitor and try again next morning.

That was this morning, and it seems to charge the battery just fine from the AC input. As I understand it, that involves the whole power train (full bridge at the AC output, buck converter, and two full bridges at the DC-DC converter on either side of the high frequency transformer). Actually, it may not involve the first two, I just don't know how the battery charger function actually works. But it's a pretty good sign. Weber didn't attempt to fire up the inverter part as an inverter, reasoning that something bad may happen because the power supply (from the battery) is not working.

I have the other board here now, and will attempt to get it working. Hopefully, the same repair will get the other board working as well. So dockarl, we think we're getting close to repairing the two boards.

[ Edit: by the heatsink -> by the fins of the heatsink; white capacitor was blocking IGBTs; visible at right end of photo. ]
[ Edit: buck converter is not in reverse when AC charging.]
Last edited by coulomb on Sat, 15 Jul 2017, 09:10, edited 1 time in total.
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.

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Post by coulomb » Tue, 18 Aug 2015, 02:48

Image

Image
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.

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Post by offgridQLD » Tue, 18 Aug 2015, 13:12

I think I need to make you guys some custom spanners (basically heat up a cheap few $2 store spanners and bend it into a funky shape to make easy work of jobs like that.

What size is the bolt head holding the fets in?

Kurt
Last edited by offgridQLD on Tue, 18 Aug 2015, 03:13, edited 1 time in total.

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Post by offgridQLD » Tue, 18 Aug 2015, 15:27

I'm just charging my 40ah/48v lithium pack with the PIP at the moment from mains power. I have the PIP set at 20A max charge. The PIP is pulling 1250w AC from the wall and its feeding 1088w into the battery. I work that out at a 5% loss or 95% efficiency. Not to bad.


One question I have regarding The serial interface board on my PIP. When I use the pip to recharge my Imiev from the little 40ah - 48v battery. I set the LVD at 48v this is 48v under load with a 2200w load on the batterys.

What I find is that at some voltage above 48v but bellow 50v (sorry I will get a exact voltage number) the relay on the Serial interface board starts clicking away. I would guess about two times pr second and continues to do so until just befor LVD where I get a break in the clicks and then they slow down.

What setting can I change to stop this or why is it doing this. Admittedly I haven't investigated it yet and will do so on the weekend when I have my coms cable handy.

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Post by weber » Tue, 18 Aug 2015, 15:34

I was, quite rightly, berated by Coulomb for not having Z (or offset) screwdrivers, which of course he has in his workshop. Image

The heads on those M3 screws are 5.5 mm hex and #2 phillips. The white capacitor definitely has to come out. It has maybe 1 mm of clearance. Even if you could turn the screws there's no room for them to come out. But the black capacitor has about 20 mm clearance from the screws which are under about a 10 mm overhang of heatsink, so a suitable offset screwdriver or open-end spanner could do the job there.

I also don't have open-enders below 8 mm (only sockets). Coulomb also pointed out that I need a miniature file set. I feel a tool shopping expedition coming on. Is there anything else I've forgotten, Coulomb?
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Post by weber » Tue, 18 Aug 2015, 15:46

offgridQLD wrote:What I find is that at some voltage above 48v but bellow 50v (sorry I will get a exact voltage number) the relay on the Serial interface board starts clicking away. I would guess about two times pr second and continues to do so until just befor LVD where I get a break in the clicks and then they slow down.

What setting can I change to stop this or why is it doing this. Admittedly I haven't investigated it yet and will do so on the weekend when I have my coms cable handy.


Hi Kurt. That's nothing to do with the serial comms. That's the so-called "dry contact" described in the manual. It can be wired to an alarm to warn you of impending shutdown on undervoltage. I think you can turn it off using setting number 18 "Alarm on/off".
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Post by offgridQLD » Tue, 18 Aug 2015, 16:09

Thanks Weber, I will dig through the setting and turn it off as listening to it for 10 min straight in the confines of the car had us all a little loopy in the end. Image

Yes some times you just can't win if the screw doesn't have room to back all the way out. It's a bit like building large objects in a workshop and then realizing it wont fit out the doors ( don't ask me how I know that one Image )

I guess my point on the tools is just a reminder that some times a simple specialized tool or just the correct tool for the job can turn a world of pain into a quick and enjoyable process. I understand some time's it's difficult to justify the expense or time spent creating them. But often there are modesty priced options out there now days or the time spent making them pays it's self off in the long run.

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Post by ChrisHobson » Wed, 19 Aug 2015, 00:00

Depending on what program 1 is set to program 12 and 13 and the low battery cut off influence the dry contact. Program 18 switches off the buzzer/alarm on the unit (gets rid of the annoying beep when you are pressing buttons on the unit and silences alarms).
Last edited by ChrisHobson on Tue, 18 Aug 2015, 14:09, edited 1 time in total.

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Post by weber » Wed, 19 Aug 2015, 00:35

Does anyone know what the conditions are that cause a PIP-4048MS to drop out of float mode, so that next time it charges it will go to the absorb voltage? What voltage does it have to drop below, and for how long? And is it a fixed voltage or is it a certain number of volts below the float voltage setting, or is it setting number 12 (back-to-utility voltage) even when the PIP is in UtI mode?

There was some discussion in this thread beginning at
viewtopic.php?title=pip4048ms-inverter& ... 332#p57546
but we did not come to any conclusion.

I need to know about this for the Black Monolith, because I was relying on going to the absorb voltage to balance the cells, and I was relying on the completion of cell balancing (all cells in bypass) to decide when to reset the SoC meter to 100%. And this was just never happening and the SoC meter was slowly drifting downwards so that eventually it was only reading 60% when it was really 100%.

The Black Monolith has 16 x LiFePO4 cells and I had the float voltage set to 53.8 V (3.36 V per cell) and the absorb voltage 55.2 V (3.45 Vpc).

I have worked around it temporarily by raising the float voltage to 54.2 V (3.39 Vpc), but this is not a good long term solution.

[Edit: Replaced "absorb voltage 54.5 V (3.41 Vpc)" with "absorb voltage 55.2 V (3.45 Vpc)"]
Last edited by weber on Tue, 18 Aug 2015, 21:17, edited 1 time in total.
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Post by Tjadenw » Wed, 26 Aug 2015, 04:49

Did you guys see the new model Voltonicpower launched

http://www.voltronicpower.com/oCart2/in ... uct_id=151

Only 1.5 and 3 KVA but the new model has got selectable output voltage, charger stage selection and CV charging time selection.

The solar charger is only 40 amp unfortunately, i wonder if a 4 Kw model will follow.

[ Edited Coulomb: made link clickable ]
Last edited by coulomb on Thu, 27 Aug 2015, 17:56, edited 1 time in total.

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Post by coulomb » Wed, 26 Aug 2015, 16:25

Tjadenw wrote: new model Voltonicpower launched

I'm not totally convinced that it's a new model, though it does have some interesting features, like a selectable 2/3-stage charger.

Thanks for pointing it out.
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.

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Post by T1 Terry » Wed, 26 Aug 2015, 17:01

weber wrote: Does anyone know what the conditions are that cause a PIP-4048MS to drop out of float mode, so that next time it charges it will go to the absorb voltage? What voltage does it have to drop below, and for how long? And is it a fixed voltage or is it a certain number of volts below the float voltage setting, or is it setting number 12 (back-to-utility voltage) even when the PIP is in UtI mode?

There was some discussion in this thread beginning at
viewtopic.php?title=pip4048ms-inverter& ... 332#p57546
but we did not come to any conclusion.

I need to know about this for the Black Monolith, because I was relying on going to the absorb voltage to balance the cells, and I was relying on the completion of cell balancing (all cells in bypass) to decide when to reset the SoC meter to 100%. And this was just never happening and the SoC meter was slowly drifting downwards so that eventually it was only reading 60% when it was really 100%.

The Black Monolith has 16 x LiFePO4 cells and I had the float voltage set to 53.8 V (3.36 V per cell) and the absorb voltage 55.2 V (3.45 Vpc).

I have worked around it temporarily by raising the float voltage to 54.2 V (3.39 Vpc), but this is not a good long term solution.

[Edit: Replaced "absorb voltage 54.5 V (3.41 Vpc)" with "absorb voltage 55.2 V (3.45 Vpc)"]


Why a 3.36v float, what was the reasoning behind that? Can your program include an equalising charge frequency and parameters? As I don't use the MPPT controller at all I have no idea of what parameters can be set, but I use this function for the Victron BMV 100% SOC reset on the charge control system we have.

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Post by weber » Wed, 26 Aug 2015, 17:35

Hi T1 Terry. When you quoted my question, I got all excited, thinking maybe you were going to answer it. Image Never mind. Image
T1 Terry wrote:Why a 3.36v float, what was the reasoning behind that?
The lower the float voltage the longer the life. Although in a place like Queensland we shouldn't forget that keeping them cool is way more important. Ideally we wouldn't float them at all but simply stop charging until the estimated open circuit voltage fell below some threshold, say 3.29 Vpc. A number of experiments have shown that the rested voltage of a fully charged LiFePO4 cell will eventually settle around 3.36 V. Also it is just sufficiently above the 3.33 V plateau between 80% and 95% SoC to be sure it is fully charged.
Can your program include an equalising charge frequency and parameters? As I don't use the MPPT controller at all I have no idea of what parameters can be set, but I use this function for the Victron BMV 100% SOC reset on the charge control system we have.

The PIP's MPPT charging parameters are the same as its 230 Vac charging parameters, and they do not include a periodic equalisation charge. Nice try though.
Last edited by weber on Wed, 26 Aug 2015, 07:37, edited 1 time in total.
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Post by solamahn » Wed, 26 Aug 2015, 18:17

I just tried a 4048 on 240 charging and the start voltage was 50.9 and it went up to the bulk charge setting of 57v. I know with 2424 the start voltage has to be below 25 for it to go into bulk charging but I did not think it mattered with a 4048. If the charging starts at a high voltage then it will not stay in bulk for long. That was using firmware 52 30. Has anyone tried changing the scc firmware. I can do it on a 2424msx but with a 4048ms I just get a debug assertion error
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Real Name: Kurt
Location: Fleurieu Peninsula, SA

PIP-4048MS inverter

Post by offgridQLD » Wed, 26 Aug 2015, 19:04

Are you thinking of what some charge controllers call a (rebulk) mode When it will go back through the bulk/absorb stage if the voltage drops below a set value while in float?

If so then no I don't think it has that particular feature. It doesn't have any programmable adjustment of the time spent in CV - absorb stage. It's more or less. Set a float - absorb voltage and max charge limit and that's it for charging adjustment.

How long it spends at CV is predetermined by the time it took to get to the absorb voltage (with a limit on the min & max time from memory (10min / 8hrs)


I took my PIP out the other day in my Imiev (Ejerycan backup) As I had a long trip to do and wasn't sure of the capacity needed to complete it. It turned out I had plenty of capacity when I got home in the stock Imiev pack. So I now had a full 2kwh 48v Calb battery that I didn't want to let sit for long periods at 100% SOC.

So I drained the pack back down to 50% SOC using the PIP powering a small 2.5kw (non inverter) style RC split system Aircon unit. It was cool at the time so I was using it in RC heat mode. It was a funny feeling sitting in a room with the thermostat set at 28C! bathed in warm...hot air. While a tiny battery and inverter where doing all the magic. I had to run it for several hrs to get the battery back down to roughly 50% SOC (Silly split system AC's and there high efficiency Image.

It was interesting to see the live consumption reading on the PIP4048's display. 630w when the compressor was running and the Meter I was running it through showed 630.1w. I then increased the fan speed on the aircon unit and the PIP4048's display read 641w and the inline meter read 640w. It was nice to see them agree somewhat. I was also suprised at how low the consumption was on that particular inexpensive no name non inverter style AC unit . (I had always just assumed it's consumption was around 1kw) so that was a nice outcome.

PIP4048's display (fan low)
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Energy meter (fan low)
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PIP4048's display fan high
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Energy meter (fan high)
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It was a good test to see how the PIP4048 handles Air Conditioner spike loads as I was considering dedicating it (when it's not in Ejerrycan mode) to run several split system Aircon units at the same time. I will have to try it on one of my inverter style units and see if it has any funny issues with it (like it did a few times with the variable load of the Imiev charger)

Kurt






Last edited by offgridQLD on Wed, 26 Aug 2015, 09:07, edited 1 time in total.

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