PMS 3h - Power Management System

@KiwiDaveNZ

i have the same battery -



as for chargers the Victron is awesome, and just works. either the IP22 or the IP65




Renogy do there own 240v charger . . . . but its pants compared to the Victron.



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FYI - CTEK & NOCO are recommended brands. . .

but weve had issues with the NOCO chargers being used as power supplies on long trips: - Noco Genius 10 not working correctly
.....


output wise for that 100Ah it will take 100A, but 10-30A charger is a more suitable range,

it just depends how long you have to charge,

example :

10A charger will take 10hours to charge a 100A lithium.


30A charger will take 3.3hrs to charge a 100A lithium.



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as for multiple charge souses . . . that's fine.

each charger will sort itself out independently.


+++++++++
 
As @Dellmassive says I am a great believer in the Victron range and would recommend the Smart Charger either 12/7 or 12/15. Bigger is better if funds allow.
 
Thanks for your advice guys, much appreciated. BTW it was @Dellmassive review on the Renogy battery that finally sold me on pulling the pin, so thanks for the really useful info. Looking into finding a Victron 12/15 Smart Charger or larger Amp rating at the best price I can (my Scottish ancestry always kicks in when shopping!). Pretty sure Victron do the fly leads so should be an easy fix. Oh and a lovely switch cover to stop any use of the PMS 3H onboard charger. Cheers!
 
I talked to my Auto electrician yesterday, and were talking about what might be needed to do the install, when it got to the low voltage battery protect. He was discussing whether or not the low voltage disconnect was necessary as the BMS has a low voltage shutoff, and suggested checking with manufacturer as to whether an additional disconnect was required. I read in the manual that " It is recommended to pair the battery with discharge equipment featuring low voltage disconnect in the system", So I would assume this would mean something like the Victron battery protect device is recommended. Just checking if a low voltage disconnect device is used/recommended by others in their setups?
 
It's not required for a lithium battery with a BMS that already has that feature.

99% of modern lithium's have this feature.

( The older green Valance lifpo4 didn't have this feature, so am external unit was needed)

I personally have removed the Victron battery protect units from my setup,, as the Roamer battery already has this feature.

Most BMS will shut down at a 0% SoC, say 10v

Some people however still use a low voltage disconect to shut off loads at say 10% or 20% .. IE 11.5v.


So ultimately it's personal preference..... Remember each conection and join adds resistance to the total install.
 
The reason I had thought the battery protect might have been useful , as you mentioned @Dellmassive , was to ensure the battery state of charge doesn't drop below a level that might start to degrade the battery. When I looked at the datasheet for the battery the BMS was going to let it drop to 10V before acting to stop discharging, I thought that was a level where the battery might degrade and was surprised that the cut off set point was so low. Sounds like it may still be useful to have the Victron there set to cut off at 11.5v (Low voltage disconnect) and reconnect at 12.8v (setting 6 on the Victron battery protection unit). Looking at the discharge curve for LiFePO4 this looks like about 7% undervoltage cutoff and 20% undervoltage restart again. Trying to keep the precious healthy, as it isn't cheap to replace.
Unless I have got the wrong end of the stick and 10V is going to be OK for the battery health, or I am misunderstanding the spec sheet on the Renogy website for the battery?
 
No, you are correct in your assumptions.

The BMS shut of point is to prevent damage to the cells..... So that's the 0% point.


By reducing the depth of discharge, you increase the cycle life expectancy.


But the Renogy still claim 4000plus charge cycles down to 80% DoD....

4000 cycles / 365days is still 10 years !!!!!

So you can drain your battery down to 20% every day for 10years.


With that in mind..... Plus having numerous lithiums now I decided to drop the low volt protect.
 
Thanks again Dell for the top advice. Will take your comments into consideration as dumping the low voltage cut-off switch saves me 30 something to 50 something quid depending if I got the BT or non BT versions of the Victron.
 
Sorry if I am hijacking the thread, but I think it’s relevant.

I too have just bought a renogy 100Ahr lithium (the one with Bluetooth), and consequently need to change the charging setup. I have just upgraded the Solar with a second panel in series, which gives me a longer charging day and up to 300W (about 250 max in reality) this runs through a Victron smart Solar, so no problems there. But I also have an older dc -dc Ctek250SA and a Maypole 8Amp mains charger. My thought is, if I get a compatible dc-dc charger to replace the Ctek, then why not connect the Existing Maypole mains charger to the starter battery with a relay to the ignition sense (might need a diode to block feedback to the main fuse box lighting up the van electrics), so that this will switch dc-dc charger and charge the lithium battery and I only have to buy one new charger (plus a relay and diode).

Anyone see any problems with this? Or is there a better way?

Many thanks. Alan
 
@Alanmh I just bought the Victron IP65 12-Volt 15 amp 230V battery charger which will also be able to kick start the Renogy if it goes into low voltage protect mode (or so I have read). I will have a permanently installed plugged fly lead to the battery to plug the charger in( the Victron comes with both M8 and crocodile plugged connectors), and has a Lithium charging profile. 141£ on Amazon. A fairly easy solution when plugged in to a socket in the van when connected up (thanks for all the advice guys). I will be interested to see if your idea is possible, might depend on the van though, my one has a smart alternator that likes to keep the starter battery at 80%. The vans system monitors the charge level in the starter battery. Not sure if any of that is relevant in your case and will leave it up to the experts to speak to your suggestion. But I am going for the simpler, but maybe? more expensive option. But I guess in your case a new B2B with a lithium charge option (as I assume your current charger doesn't have a Lithium profile) is going to cost a pretty penny which you have to get anyway as you can't charge the Lithium from a relay setup from the alternator (I think my Stirling BB1230 was about 230£).
 
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Thanks - I have just ordered the Victron 12/12-18 (18amp Dc to DC) and bonus, I just read that it will charge in parallel to my Victron smart solar charging. Looks like I may never need hook up again!
 
Sorry if I am hijacking the thread, but I think it’s relevant.

I too have just bought a renogy 100Ahr lithium (the one with Bluetooth), and consequently need to change the charging setup. I have just upgraded the Solar with a second panel in series, which gives me a longer charging day and up to 300W (about 250 max in reality) this runs through a Victron smart Solar, so no problems there. But I also have an older dc -dc Ctek250SA and a Maypole 8Amp mains charger. My thought is, if I get a compatible dc-dc charger to replace the Ctek, then why not connect the Existing Maypole mains charger to the starter battery with a relay to the ignition sense (might need a diode to block feedback to the main fuse box lighting up the van electrics), so that this will switch dc-dc charger and charge the lithium battery and I only have to buy one new charger (plus a relay and diode).

Anyone see any problems with this? Or is there a better way?

Many thanks. Alan
Yes you can do this....

I have tested it out....

I call is Auto VsR feature.


The mains charger raises the starter battery voltage to the post by when the dc-dc charger will kick in (even without the IGN signal).

This will then charge your leisure battery....


But testing shows that as @KiwiDaveNZ says the starter is kept at 80%, so you loose the first 20% before the dc-dc kicks in to charge the LB.

I found that the charger will cycle on and off..... But ultimately both battery will get a charge.

I found that the more powerful a main charger you have works better..... Ie tested with a 15A charger.


And that the Victron charger worked particular well as you can tweak the charge voltage to reduce cycling....

Ultimately the best option is for twin mains charger s...

Say a 5A for starter and 15A for LB.
 
More info.


.
 
Thanks @Dellmassive , I knew it worked with the CTEK, but wasnt sure about the Victron Dc to DC. I have the 15Amp Victron on order as that keeps all my cables the same and I have never seen the old AGM battery pull more than about 12/15 Amps from the CTEK, normally its around 10amps at most. Looking forward to the lack of voltage drop from the lithium when the fridge compressor kicks in!
 
Hello, sorry, only just seen the little notification icon that said someone had replied...

I ended up fitting my Victron IP65 charger to the side of one of my cupboards with the idea that when charging on hookup I'd just plug it in to one of the van sockets. I've wired the battery up with the chargers M8 connectors so that I don't have to connect crocodile clips. I have however found that since first charging it up at home with the Victron, I've not had to charge it again yet. It's 200ah and my Sterling B2B charger has kept it well topped up on the return drive from wherever we've been. I was thinking of getting a suitcase solar panel for emergencies but we can probably do 10 days completely off grid with our average use so I'm not sure it's worth it.

One thing to note, the lithium profiles on my Sterling and my Victron were slightly different to the recommended settings of the battery manufacturer (Roamer). I ended up setting up custom charging profiles which was easy enough to do.

I've still not found out how to properly disconnect the PMS battery charger, it's not been wired in the way the manual suggests. My red "Charger supply" button has to be on or no EHU power gets through to anything. It means that if I'm on hook up, I have to keep the battery button "OFF" so it doesn't charge anything. Ideally, I'd like to kill the charger altogether, but I'll probably just wait until I've time (and have someone with me who knows the regulations) and remove the PMS altogether.
 
Hello, sorry, only just seen the little notification icon that said someone had replied...

I ended up fitting my Victron IP65 charger to the side of one of my cupboards with the idea that when charging on hookup I'd just plug it in to one of the van sockets. I've wired the battery up with the chargers M8 connectors so that I don't have to connect crocodile clips. I have however found that since first charging it up at home with the Victron, I've not had to charge it again yet. It's 200ah and my Sterling B2B charger has kept it well topped up on the return drive from wherever we've been. I was thinking of getting a suitcase solar panel for emergencies but we can probably do 10 days completely off grid with our average use so I'm not sure it's worth it.

One thing to note, the lithium profiles on my Sterling and my Victron were slightly different to the recommended settings of the battery manufacturer (Roamer). I ended up setting up custom charging profiles which was easy enough to do.

I've still not found out how to properly disconnect the PMS battery charger, it's not been wired in the way the manual suggests. My red "Charger supply" button has to be on or no EHU power gets through to anything. It means that if I'm on hook up, I have to keep the battery button "OFF" so it doesn't charge anything. Ideally, I'd like to kill the charger altogether, but I'll probably just wait until I've time (and have someone with me who knows the regulations) and remove the PMS altogether.
Could always get it wired up correctly, it shouldn't be wired like that, it certainly isn't on mine, so probably could be pulled by an electrician/ auto electrician and sorted. The manual agrees with the way mine is wired. As I said in a previous post I bought a switch cover to stop the charger switch being enabled, not much good to you until it's sorted though.
 
Could always get it wired up correctly, it shouldn't be wired like that, it certainly isn't on mine, so probably could be pulled by an electrician/ auto electrician and sorted. The manual agrees with the way mine is wired. As I said in a previous post I bought a switch cover to stop the charger switch being enabled, not much good to you until it's sorted though.
I'm not sure it even makes sense wiring it the correct way (if indeed it has been wired a different way). The switch that says "Charger Supply" needs to be ON for the EHU to work. Seems odd to call it Charger Supply if it's just the ON switch for the whole unit, and that there's no actual switch to then turn the battery charger component on or off.

I've heard these units aren't that good, and my van also has a separate blade fuse for the fridge underneath the PMS, one for the poptop lights and one for the PMS unit and one for a voltage display. It seems like a bit of waste to have the big black box thing just to host the EHU, 3 sets of LED's and the water pump.

I'll probably just leave it alone, it all seems to be working fine and at least I understand how it works if not why it's been done like that. Until I'd got a lithium battery, it was trouble free operation apart from the internal PMS battery charger not being up to fully charging my old battery.
 
I'm not sure it even makes sense wiring it the correct way (if indeed it has been wired a different way). The switch that says "Charger Supply" needs to be ON for the EHU to work. Seems odd to call it Charger Supply if it's just the ON switch for the whole unit, and that there's no actual switch to then turn the battery charger component on or off.

I've heard these units aren't that good, and my van also has a separate blade fuse for the fridge underneath the PMS, one for the poptop lights and one for the PMS unit and one for a voltage display. It seems like a bit of waste to have the big black box thing just to host the EHU, 3 sets of LED's and the water pump.

I'll probably just leave it alone, it all seems to be working fine and at least I understand how it works if not why it's been done like that. Until I'd got a lithium battery, it was trouble free operation apart from the internal PMS battery charger not being up to fully charging my old battery.
The charger supply switch should only enable/disable the battery charger (which is why it's labelled charger supply), not the 240v 3pin power sockets and lights etc. They are enabled via the pms when plugged in to the external supply for the PMS 3H. The PMS also has fusing for the 240v side. Something weird going on there. The switch should be for the battery charger only and in your setup you can't switch the charger off without disabling everything. Hopefully one of the auto electrical guys here can explain why yours is setup the way it is. Good luck with it.
 
Hi Guys, new to this forum and having some difficulties with my PMS3 fitted to my T5. I have it wired to the leisure battery only as I don’t want do draw anything from the starting battery. I have a split charge relay topping up the battery on the move but plugged into EHU I can’t seem to get the battery charger to work. The light comes on when selected on with the RCD and 3rd CB engaged. I have a good chassis return which I have checked with a multi meter. The PMS unit is connected directly to the leisure battery and to the chassis. When selected to Van I’m not getting any increase in voltage. Trying to keep my fridge running when on hook up without depleting the leisure battery
 
@Tomlowe242 I think you need to go back to basics and check the wiring on the PMS. Do you only get 12v system supply when Van is selected? Does the 240v side all work OK even when charger is off and the output selector is in the central position. The charger is very poor and only puts a small current into the battery. Most people with PMS use a Victron type charger run off your 240v outlet to charge the leisure battery whilst on hook up.
 
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