Ultimate speed miroprocessor charger

[snow leopard]

Can anyone give a definitive answer as to whether it is safe to connect a microprocessor type charger to the car battery without disconnecting the battery from the car? After searching the forum I have come across several members' posts which say that they do it and that it is safe. I then find MB saying don't unless it's theirs' - is this just commercial protectionism? CTEK say it's safe. Ultimate Speed (currently in Lidl with an appealing price tag) advise that the battery should be disconnected - is this a 'liability caveat'? I've also read in the Auto press that with such a diminuitive price tag, this is a brilliant piece of kit.

From my understanding, whether it's CTEK, MB (some have said MB is a badged CTEC) or the cheapo Lidl offering, a microprocessor pulse charger is all the same physics - I do hope I'm right on this but then again I'm not an electronics engineer and I am pretty worried about some potentially very expensive consequences. I really would like to risk £14 on the supermarket special but I'm even more adverse to risking my car electrics. If OK, I'd plan to hook it up via the jump start terminals.

Really grateful if anyone with solid knowledge/experience can advise.

 

[190]

One definitive answer would be to monitor the voltage while charging. MB's concern is about not exceeding a voltage declared to be safe to the cars electronics. The figure I've seen for this in an online W204 C class owners manual was 14.8 volts. I very much doubt any small charger would exceed that figure.

Short of buying one to test the voltage do CTEK publish any technical data for their charger ?

 

[whitenemesis]

MB's own charger is a rebadged Ctek. I have such a charger with a convenience connection fitted by MB. I regularly charge my battery without disconnecting the battery, just as MB does in their workshops.

Ctek's website details all the charging characteristics of their chargers. The pertinent value is the ripple current. Too high and it can adversely affect the car's system. Ctek values are very low and perfectly safe to use connected.

Personally I would steer clear of Lidl's offering

 

[renault12ts]

Definitively, yes.

 

[Andyjb]

If LIDL's is similar to ALDI's then I would not risk it. I bought one but tried it on my spare battery on the bench first. The charger output went up to 16.7 volt! I took it back and had a refund! That voltage would have upset my Merc!

 

[richard]

Don't blow your car up. Any cheap small charger can still (and very easily) provide too higher voltage. They can't provide much current, but it doesn't take much current to break things.

The electronics in your car is far too expensive to risk busting it

Buy Merc one or CTEK

Richard

 

[flango]

My pals got an Aldi special on his Ferrari 458 Aldi one is equiv or better spec than ctek. German made tuv approved.

 

[snow leopard]

Thanks for replies, especially the cautionary notes. Seems wise not to risk it so looks like it'll be the Ctek jobbie for me!