MegaPulse

[jimbaerselman]

I appreciate that.

As I understand Megapulse is claimed to work by providing a high frequency pulsing at the 'the natural frequency of the battery', whatever that means. I assume it means lots of tiny high voltage pulses - and since it doesn't heat the battery (at those mA it couldn't!) it's obvious that those pulses are of a very short duration compared to the 'non-pulse' periods.

I believe the actual battery charging for megapulse is done from an additional source. though that may not be necessary for your tiny torch battery.

Incidentally, I think (this is memory again, fallible stuff!) that the Sterling de-sulphating cycle is a 16v steady voltage of relatively short duration - tens of minutes - cut off using time or a battery temperature sensor, whichever shouts first.

The battery manufacturers do not say that megapulse doesn't work, but they are skeptical that it has any advantage over standard, high voltage techniques for de-sulphation.

 

[Anonymous]

The MegaPulse (and all the other pulsers I've come across) are two-terminal devices that you connect across battery terminals (right onto the battery posts themselves, ideally) with croc clips, if you like. The device takes the dc from the battery and converts it, using a dc-dc convertor, into the voltage it needs for a pulse. The pulse is then sent into the battery usually via a capacitor to isolate the pulse circuitry from the dc circuitry. It could also be transformer or inductively-coupled. Not other form of charging is needed to make a MegaPulse work.

The peak current from the pulse discharge could be quite high - tens of Amps, I don't know what is used in these designs in practice - but the average is around 0.050A and this needs to be replaced or the battery will go flat over time. Most yachtsmen would, I imagine, leave theirs running all the while they have some kind of charging, mains, wind or solar, and switch it off when leaving the boat without charging or when trying to get weatherfax, RTTY, or having trouble with Navtex.

 

[VicS]

[ QUOTE ]
The MegaPulse ................

[/ QUOTE ] That is exactly my understanding.

The current drain varies between models. One of those from Courtiestown draws 100mA. So that will run a 90Ah battery flat in a bit over a month. Therefore not suitable for permanent connection without regular charging.

 

[jimbaerselman]

Yep. That makes sense. You'd need a big enough volt-jolt to create 10 to 20 amps to crack the crystals. Then you'd spend about 500 times the length of the jolt to re-charge the capacitors for the next jolt.

Sterling's jolts are just much longer (and incidentally charge the batteries) and have 7 days between jolts.

Same idea. Different frequencies. Both ideas covered with a bit of flannel to 'prove' that solution a is better than solution b, when, in fact, they're possibly identical in effect, even though the time scales to reach the effect may differ.

 

[Anonymous]

[ QUOTE ]
Sterling's jolts are just much longer (and incidentally charge the batteries) and have 7 days between jolts.

[/ QUOTE ]I don't think so. If you read what they say (above) you would infer that they don't think that a pulser (as described in my last post) is included in any Sterling. You wouldn't run a pulser every week, you leave them running 24/7. There is no published literature on pulsing for a few hours a week so how would they know that it would work, even? Sterling, as a policy, actively discourage (=ignore) emails but they pride themselves on their phone support. I can't do that from Spain but maybe one of you could give Mr Sterling a ring and get it from the Horse's mouth /forums/images/graemlins/wink.gif

In past discussions I've found him to be very unhelpful when it comes to a straight answer to a technical question.....if he doesn't think you need to know he will tell you that you don't need to know - in no uncertain terms! I doubt you'll get a straight answer, but it would be an interesting exercise.

Tell you what, if anyone thinks otherwise, I'll pay a fiver to The Salvation Army if I'm wrong, if they will pay a fiver to a charity of their choice, if I am right? In other words, if Mr Sterling says, in a clear and unambiguous manner, that his chargers give a pulse output of a similar electronic form to the MegaPulse (which, incidentally, looks absolutely identical to his own Pulser, so he has probably badged a MegaPulse) then the Sally Army gets a fiver. I won't mind, it's a good Christian charity appropriate at this time of year, anyway!

 

[jimbaerselman]

I think you mis-understood me. I'll posh up my English!

Sterling's de-sulphating method is to apply a constant 16v for some period (tens of minutes?) once a week. The rest of the time the battery will be on a 13.6 maintenance voltage.

I was drawing the parallel that that is just pulsing, but in a very slow motion form compared to 'megapulse'. The one has a cycle of seconds, the other has a cycle of days. Many battery manufacturers argue that there is no measurable difference between the methods . . .

Any clearer?

 

[Anonymous]

We are discussing a battery desulphator working on low energy current pulses 24/7, that is the subject of this thread. If a battery charger manufacturer decides to include some other kind of anti-sulphation technology then that's fine, but it should not be called a pulser, if it isn't a pulser. Regular equalisation periods have been industry practice for well over a decade, pulsers are only starting to be accepted as mainstream technology. I am not aware of any charger manufacturer who has an integral pulser.

Sterling sell pulsers that look physically identical to the MegaPulse. They sell chargers that don't claim to pulse but they claim that they don't need pulsers because they have equalisation cycles. Maybe that is as good, maybe it isn't, but they should not confuse two entirely different technologies. Personally I doubt whether the regular equalisation cycles can desulphate a battery. I have never seen any evidence that they can.