I am sceptical about the desulphator, but as a new set of batteries
costs me
300 euro, I thought, let's give that 30 euro kit a try. Of course not
knowing that it would kill my 200 euro charger...
To get some more info on my spikes, I just connected a capacitor and
a
diode. It showed 62 volts. Oops. This must certainly have been the
cause of
my charger problem.

The logic of the charger seems to be fine and looking at the amount
of
gassing it also seems to be putting out plenty of current. I did saw
at
least one FET inside and will go and check out that one and others
that I
can find. I tried to find a schematic, but couldn't.

The funny thing indeed is that this charger has a built in
desulphator. This
also led me to think that desulphators could work. If a reliable
manufacturer like CTek is building it into its chargers... The problem
that
is that the CTEK only stays in desulphation mode for about 5 seconds.
I
cannot imagine this to be effective at all. Therefore a tried the
desulphator
kit.

The desulphator comes from Courtiestown:
http://www.courtiestown.co.uk/batter...ust%202011.pdf

Thank you all for your comments. I hope I'm lucky and can get it
running again. Will keep an eye on the peak voltage of the desulphator
too, to see if mine is perhaps dropping.

Joost

On 26 mrt, 01:44, Jeff Liebermann wrote:
On Sun, 25 Mar 2012 14:40:56 -0700, mike wrote:
There are lots of claims made by desulphator vendors. *I've never read
anything, outside the vendor sphere of information, that said they
worked at all. *My experiments agree that they don't work.

I agree. *I maintain several mountain top radio and weather station
sites, all on various mutations of battery power. *Various experts
have arrived with desulphators and magic anti-sulphation potions
(EDTA), none of which have done anything beyond a short term revival.

One problem is that none of the articles I've read that proclaim
miraculous battery rejuvenation bother to run before and after tests.
I have a West Mountain Radio CBA-II battery tester.
http://www.westmountainradio.com/product_info.php?products_id=cba3&na....
With a 10A discharge rate, the L16 batteries that I usually use (2V
465A-hr) take about 4 days to hit the knee in the curve. *Your T105
(6V 225A-hr) should take about 2 days. *However, that's with a new
battery. *What I've found is that a pre-treatment battery, may have
about 1/4th of it's original capacity, while a post treatment battery
will have even less. *The post treatment battery will "take a charge"
better than one that seems sulphated, but the discharge capacity isn't
there.

Diversion: *When you discharge a wet cell battery, you solve the lead
plates into the electrolyte solution. *When you charge the battery,
you electroplate the lead back onto the plates. *It never quite goes
on the same way it came off. *Do it often enough, or too fast, and the
lead plates start looking like a coral reef with attendant loss of
capacity.

What's happening is the result of doing a post mortem on only one
battery, so this is admittedly rather anecdotal. *What desulfation
does is remove the coating of lead sulphate from the lead plates.
That's fine, except that by the time the battery becomes sulphated,
the normally porous (sintered) lead plates, now look rather like a
coral reef. *Exposing more of the lead plate surface should will
improve the ability to take a charge, but the discharge is still at
the mercy of the lack of sufficient surface area, and that's going to
be as bad or worse than what you started. *Worse, the shock treatment
of de-sulfation can cause chunks of lead sulphate to fall off the
surface of the lead plates and fall to the bottom (i.e. deep cycle),
taking some of the coral reef looking lead to go with it. *The
reduction in the amount of lead in the battery plates will have a
detrimental effect on future charge/discharge cycles.

Links to a typical crude desulphators:
http://homepower.com/view/?file=HP77_pg84_Couper
http://home.comcast.net/~ddenhardt201263/desulfator/desulf.htm

Good battery advice:
http://batteryuniversity.com/learn/article/sulfation_and_how_to_preve...
http://batteryuniversity.com

As for connecting two charger in parallel, you're lucky that one of
the chargers didn't blow a fuse, or an internal component. *Don't do
that again. *If you RTFM at:
http://www.baintech.com.au/download-document/37-ctek-xs-15000-user-ma...
it says:
* *"Do not place the charger on the battery while charging"

You're probably going to want to probe around in it live with an
oscilloscope.
Looks like an offline converter that can be dangerous to service without
proper equipment (AKA You get dead).

I couldn't find a schematic of the CTEK MULTI XS 15000 which might
help with a repair. *On paper, it looks like a really nice battery
charger. *My guess(tm) is that the desulfation contrivance is capable
of producing some rather high voltage pulses. *Those could easily have
destroyed whatever output power FET's are inside.

Make and model of the desulfation device?

--
Jeff Liebermann * *
150 Felker St #D * *http://www.LearnByDestroying.com
Santa Cruz CA 95060http://802.11junk.com
Skype: JeffLiebermann * * AE6KS * *831-336-2558