PMS 3h - Power Management System

[Phil_G]

Andy, Keighley to Kidderminster is just a hop in the van! Martyn has kindly offered to take a look at your power problems so
make it a day out, take the van to Martyn's, then take the family to West Midlands Safari Park.
Or you could camp over and make a weekend of it. If you do need to buy anything, you will struggle to better his prices.
You've already experienced one dodgy installer, dont be caught out by another just because he's local.
...and the Safari Park is a fantastic day out
JMHO
Phil

 

[andy greenwood]

Andy, Keighley to Kidderminster is just a hop in the van! Martyn has kindly offered to take a look at your power problems so
make it a day out, drop the van at Martyn's, then take the family to West Midlands Safari Park.
Or you could camp over and make a weekend of it. If you do need to buy anything, you will struggle to better his prices.
The Safari Park is a fantastic experience
JMHO
Phil

Hi Phil

Thanks for your reply, is Martyn actually travelvolts ? I'm just in conversation with him at the moment with regards travelling down there and getting whatever is needed to sort it all out

 

[Noddy996]

Any update as to what you had to have done Andy? We have the PMS3 in our van too, and I am now concerned about its unsuitability after reading this thread. What did Martyn recommend / do to your van to rectify things?

 

[Teesix]

Yes, I'm afraid that the same applies to the Sargent units.

Is this the case for ALL Sargent units?

My van gets converted in Feb and the unit the converters are fitting is a Sargent ec155 power supply unit ec50 control panel 240 volt and 12 volt harness.

Should I also be concerned?

 

[Spaghetti]

I have a PMS3, and can confirm that it won’t charge your van on the move.

My converter also fitted a simple split charge relay. The first weekend away, the leisure battery got very low, and the split charge relay tried to dump a large current into the leisure battery and it blew the 40a fuse.

I pulled then split charge relay out and fitted a CTEK 250SA. When driving, this takes whatever voltage the starter battery has, and outputs up to 20a of the appropriate voltage to charge the leisure battery. The gets round the variable output from the smart alternator.

This now ensures that the leisure is nicely topped up when we arrive at our camp site.

Pete

 

[Mark T]

Hi guys hope you don't mind me adding my ten pennies worth to the discussion, I had a similar PMS3 set up to Andy fitted in a T6 with regen braking, but I definitely had a split charge relay positioned under the drivers seat near the leisure battery. I also had an unfused length of wiring from the starter battery to the relay and leisure battery. He had also attached a return cable to the negative terminal of the battery adjacent to the vw current control gizmo. My installer said it would all work fine to charge both starter and leisure batteries. It didn't!. Travelvolts Kindly fitted me a Cetek bat to bat charger and it now works fine. Thanks a bunch Martyn.
Mark from Kent

 

[Dad19]

Hi everyone
Newbie alert. I also have pms3 but also have 50w solar panel and charge controller. Will this charge the battery fully

 

[travelvolts]

The solar panel is a bit on the small side but if you have a good controller it should give the battery a decent charge under bright skies during the summer. The PMS will not charge your battery.

 

[Bigmandenz]

Hi guys, just read this with great interest, we have a pms3, I was under the impression that when i was on electric hook up, that would power the 12v system in my camper van, this is the 1st time we’ve been away this time of year and after 4 days the leisure battery has gone flat. Is there something I need fit to get this working properly ? We’ve been running the fridge, tv, lights and mobile chargers on the 12v. The only 240v socket we have, runs the kettle and that’s working fine, fortunately

We converted the van in April and had a solar panel put on the roof, we were away for 3 weeks this summer and had no issues.

many thanks

 

[Spaghetti]

Seems strange.... is the ‘charger’ on the PMS3 on, with the neon in the switch illuminated?

I presume you have the battery selector on the leisure battery and not the starter battery?

Mine will maintain the leisure battery indefinitely if on 240v hookup with the charger on and leisure battery selected. It would be better if it was a smart charger, as this would be less likely to cook the battery, but hey.

 

[Bigmandenz]

Yes, battery selector is on van battery and neon indicator is on. Will turn the engine in tomorrow morning to see if they come back, will also look at buying a smart charger and getting someone to fit it for me

 

[Spaghetti]

Yes, battery selector is on van battery and neon indicator is on. Will turn the engine in tomorrow morning to see if they come back, will also look at buying a smart charger and getting someone to fit it for me

Likewise, I was going to fit a smart charger on the spare MCB output and use that instead of the PMS3 power supply, as it’ll look after the battery better.

Do you see a voltage rise on the leisure battery when you switch the power supply on? Either by using a volt meter or the little LED bar graph?

 

[DilbertOntour]

If I do get an external smart charger and connect tot he spare MCB output how do I connect in the 12V circuit? The PMS3 is at the back of the Van and the battery under the drivers seat. Can the battery charger be added in series with the load? I,e, positive to the battery, negative to the positive on PMS3 and negative to battery negative?

 

[Deaky]

If I do get an external smart charger and connect tot he spare MCB output how do I connect in the 12V circuit? The PMS3 is at the back of the Van and the battery under the drivers seat. Can the battery charger be added in series with the load? I,e, positive to the battery, negative to the positive on PMS3 and negative to battery negative?

Your charger must be connected in parallel

 

[travelvolts]

On the back of the PMS is a row of 12 volt connectors. You can connect the output from your charger here. Find the terminals marked Bat + and -

 

[Boilerman]

Sorry to disillusion you but the PMS 3 will not charge your leisure battery correctly, either from the engine of from the mains. You will find that your battery slowly loses its full charge over a period of time and will subsequently be damaged beyond recovery.
You need a DC-DC charger to charge from the alternator and the PMS mains "charger" is only really a power supply for your 12 volt circuits when hooked up to the mains. At 13.8 volts it will maintain a full battery will not charge a depleted one.

Hi travelvolts,
What I can’t get my head round is, how are these pms 3 units allowed to be sold as being capable of charging a camper car battery & leisure battery even though they are not upto the job?

 

[Phil_G]

Its not really that they are "not up to the job", theirs is a different job to charging - to provide a stable, regulated voltage for your 12v ancilliaries.
A proper charger on its absorbtion stage would be feeding your 12v TV etc with nearly 15v, which may exceed its safe spec. So neither a smart-charger or a PSU are individually ideal. The PSU method is ok as long as the leisure battery is never discharged - ie its on permanent 13.8v float. Occasionally and after any significant discharge it needs the full bulk/absorbtion/float cycle to get back to 100%. A PSU cant do that, it can only float. Some have both, on hookup the 12v system runs off a PSU - whilst for charging, a relay isolates the leisure battery from the 12v rail so the smart-charger can do its full cycle without overvolting anything sensitive.
Cheers
Phil

 

[Boilerman]

Its not really that they are "not up to the job", theirs is a different job to charging - to provide a stable, regulated voltage for your 12v ancilliaries.
A proper charger on its absorbtion stage would be feeding your 12v TV etc with nearly 15v, which may exceed its safe spec. So neither a smart-charger or a PSU are individually ideal. The PSU method is ok as long as the leisure battery is never discharged - ie its on permanent 13.8v float. Occasionally and after any significant discharge it needs the full bulk/absorbtion/float cycle to get back to 100%. A PSU cant do that, it can only float. Some have both, on hookup the 12v system runs off a PSU - whilst for charging, a relay isolates the leisure battery from the 12v rail so the smart-charger can do its full cycle without overvolting anything sensitive.
Cheers
Phil

Thanks for your reply Phil.
I have the pms 3 in my van, do you know of a smart charger that would work well in tandem with my pms 3?
Cheers,
Gordon.

 

[Phil_G]

Its hard to say, it depends on your usage, your consumption rate, duration of battery-only use, duration of hook-up use, how frequently you are away - there are so many variables that you would be best discussing the whole project with an expert like Martyn. For most "light users" (LED lights, TV & phone charger) floating would probably be fine for the duration of a holiday, then you can manually do a proper charge cycle on your return home. Many top-notch converters use the PSU method, but thats not to say its optimal

 

[Boilerman]

Ok, I’m a light user then, lights, TV & usb. So, just for my clarification. The PSU basically controls & maintains a constant 12v to the consumers from both the leisure battery power supply & the 240v hook-up supply while supplying a float charge to the leisure batteries when the charger switch is on that selection?

Gordon.