Battery Charging - Main Battery Chassis Point -
- Thread starter Dellmassive
- Start date
Wow that leisure batteries pegged out 100% propper.... wish mine looked like that.
All that said... all looks normal, re 80% starter.
All that said... all looks normal, re 80% starter.
Look good right? And that was after 1 week camping, charing multiple devices every night, and without starting the engine at all for 5 days! Credit goes to Jason @Absolut5 for a GREAT installation of top quality kit it seems!
Sweet I'm assuming you have a solar panel hooked up to that DS250 to keep it that charged for a week.
Can you share/list out your setup for us pls?
Nope - no solar panel at all!! Just the B2B via the DS250...
In terms of the setup, this is the list that Jason sent prior to fitting:
- Mains hook up/leisure battery
- Under bonnet socket
- Extension lead
- Consumer unit
- 105 AGM leisure battery (safer and last longer than a normal leisure battery)
- 10a stage charger
- Ctek D250sa B2B charger (designed for stop/start tec)
- Fuse holder
In terms of sockets:
- 2 x CBE 12v & 240v twin sockets
- LEDs and USB that Leighton Vans installed re-connected to Leisure battery instead of Starter...
I'm yet to use the hookup / charger as the B2B has been so good (or at least that's what it seems!)
Worth saying that @Absolut5 did a SUPER neat job too!
In terms of the setup, this is the list that Jason sent prior to fitting:
- Mains hook up/leisure battery
- Under bonnet socket
- Extension lead
- Consumer unit
- 105 AGM leisure battery (safer and last longer than a normal leisure battery)
- 10a stage charger
- Ctek D250sa B2B charger (designed for stop/start tec)
- Fuse holder
In terms of sockets:
- 2 x CBE 12v & 240v twin sockets
- LEDs and USB that Leighton Vans installed re-connected to Leisure battery instead of Starter...
I'm yet to use the hookup / charger as the B2B has been so good (or at least that's what it seems!)
Worth saying that @Absolut5 did a SUPER neat job too!
Oh. Ok. So were you running the van engine for a while each day.... when you was away for a week to keep that leisure battery at 100%?
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Interesting... actually, no! Didn't run the engine at all until the day we headed home... Basically, the battery sense showed 100% for the first couple of days (even though we were charging from USBs) and then you see it drop down to 70% on the final day (when I charged my laptop), before returning back to 100% on the journey home.
I'm presuming the earlier bits of returning back to 100% on the graph are just some sort of "recovery" as the sensor settled / temperature changed, as I definitely didn't start the van, so couldn't have been charging?
Ok... you must be drawing a very low load then.
For some reason I thought you had a fridge running somehow......but if it was just usb charging points... then that may explain the very low draw...
If you was running a cooler box or fridge the draw would be higher and you would see the drain overnight etc.
For some reason I thought you had a fridge running somehow......but if it was just usb charging points... then that may explain the very low draw...
If you was running a cooler box or fridge the draw would be higher and you would see the drain overnight etc.
My experiences with CTEK Battery Sense monitors (2 of them):
The good: the voltage readings seem to be well calibrated - within 0.01 Volts from each other - and a calibrated voltmeter. So that looks good.
Not so good: the algorithm estimating state of charge seems not be worth of much in everyday use (e.g. starter battery). The algorithm probably assumes being hooked into battery at rest as very willingly recording sag of voltage as severe permanent discharge and very reluctantly "accepts" charge.
Below a snapshot where starter battery is discharged for 15 mins by 12 Amp load (Webasto aux heater) before starting the engine and setting off. Then driven 35 mins alternator charging at 14.8 Volts. The above twice a day.
So why I think the SOC shown is totally wrong. The snapshot was taken after 12 hour rest (02 Apr 06:33) - note the voltage at 12.50 Volts (verified with multimeter + van's own battery management). 12.50 Volts at rest is an indication of approx. 80% SOC.
Anyways, CTEK Battery Sense seems to keep good track of batteries at rest - so suitable for monitoring batteries in parked/stored vehicles. Actually, in July CTEK slipped out a software which instead of vague SOC chart (as above) showed actual recorded voltage/temperature values (similar to BM2-monitor charts). However, the software was withdrawn in few days.
The good: the voltage readings seem to be well calibrated - within 0.01 Volts from each other - and a calibrated voltmeter. So that looks good.
Not so good: the algorithm estimating state of charge seems not be worth of much in everyday use (e.g. starter battery). The algorithm probably assumes being hooked into battery at rest as very willingly recording sag of voltage as severe permanent discharge and very reluctantly "accepts" charge.
Below a snapshot where starter battery is discharged for 15 mins by 12 Amp load (Webasto aux heater) before starting the engine and setting off. Then driven 35 mins alternator charging at 14.8 Volts. The above twice a day.
So why I think the SOC shown is totally wrong. The snapshot was taken after 12 hour rest (02 Apr 06:33) - note the voltage at 12.50 Volts (verified with multimeter + van's own battery management). 12.50 Volts at rest is an indication of approx. 80% SOC.
Anyways, CTEK Battery Sense seems to keep good track of batteries at rest - so suitable for monitoring batteries in parked/stored vehicles. Actually, in July CTEK slipped out a software which instead of vague SOC chart (as above) showed actual recorded voltage/temperature values (similar to BM2-monitor charts). However, the software was withdrawn in few days.
Totally agree with you and your readings re the ctek units. . . thats why i have moved over to the BM2`s now. (ctek still connected to see the comparison)
same as you . . . the ctek is to Conservative and always shows very poor battery levels . . . . even though i know they are good. I think they need to tweek the algorithm a bit.
here is current ctek
and bm2 readouts.
.
Yes, the BM2's are definitely worth their price - at best they have been sold for less than 20€. Even their accuracy is good enough. Below a screenshots of three BM2's and a CTEK all connected into same battery (CTEK reading is +0.01 Volt above calibrated value). The app BM3 besides being capable to show several BM2's on same screen has a capability to export an Excel file with all the collected data of a month. Both apps BM2 and BM3 connect to the same BM2 -modules - very convenient.
I've just plugged my charger in and put it across both terminals - It is a CTEK XS 3600 I think - Do I need to change it?
My van does not seem to have a sticker saying not to charge across the battery though...
My van does not seem to have a sticker saying not to charge across the battery though...
By connecting across the battery terminals you are bypassing van's own battery management system (the gadget at battery's negative terminal) which takes into account currents in and out of the battery. So definitely it would be better to move charger's negative clamp to van's chassis (e.g. battery fixing bolt).
I did that - My charger then went from showing red (charging) to green (charged).
Would that be due to the battery management system?
Would that be due to the battery management system?
No - the gadget at the negative terminal is just a current shunt - which won't effect any current flows in or out.
Are you sure the electrical connection to van's chassis through the bolt is good. Sometimes there might be a layer of paint in the thread effectively isolating the bolt from chassis. Perhaps connecting back to battery's negative terminal to see if it's different then.
I f you have stop/start, bluemotion. Then yes, as above use any other earth point.... do not use the battery negative terminal.
But.
If you dont have stop/start bluemotion then is doesn't matter and you can use the battery negative post.
Where is the best place to buy the BM2 units from? Are they all the same?
Ebay or Amazon...
They are all the same...
Though I've just imported a couple of lithium versions..... which are the same with modified firmware.
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