Porsche 911UK Forum

Welcome to the @Porsche911UK website. Register a free account today to become a member! Sign up is quick and easy, then you can view, participate in topics and posts across the site that covers all things Porsche.

Already registered and looking to recovery your account, select 'login in' and then the 'forget your password' option.

CTEK Chargers

Ocean Blue

Well-known member
4 Jul 2009
After reading and contributing on some threads for the CTEK charger I wrote to CTEK. Here are some technical clarifications from Tony Zeal at CTEK UK.

Hi Peter
Sorry for the delay in getting back to you, if I can try to answer your questions in turn

1) Can a scenario exist where the battery will give off Hydrogen gas, which, if the bonnet is closed will accumulate. The Lower Explosive Level (LEL) for Hydrogen is low at 4% by volume i.e. 40,000 ppm.
It is hard to believe this could happen during normal charging conditions either via the vehicles alternator or the CTEK charger (unless either goes faulty).
It is common for modern vehicle batteries to be fitted in a sealed container or in the passenger compartment with no danger.
CTEK 's precise control over voltage and amperage whilst charging minimizes the emissions of Hydrogen gas from the battery .

2) Will closing the bonnet on the 12VDC cable for the 911 cause any potential issues such as cable chaffing whereby the chaffing could give cause for catastrophic failure.
From the charger point of view this will cause no damage, it will automatically stop charging as it sees an open circuit.
From the battery point of view trapping the cables like this could cause a short which could result in melted wires.
Closing the bonnet with a potential risk of damage to any cable is not a good Idea.

3) Would you consider fitting an inline fuse to the CTEK cable adjacent to where the connection to the battery is performed.
Many CTEK charging accessories have an in line fuse fitted, this is a good way of reducing the risk of shorting. There has been some
investigations striving to develop a fuse integrated in the cable or clamp. This may be a solution in the future.

4) Have you given any thought to the connector plug that connects the two battery leads together in close proximity to the battery a public health risk.
The length of cables from the battery posts to the connector reduces the risk of a spark in the proximity of the battery.
The CTEK charger is spark free , however the DC side of the system should always be connected first and then the AC
further reducing the risk of sparking.
There is available as an accessory a cig plug connector that will charge safely through the cigarette socket – this is actually a Porsche part

Thank you for raising your concerns I hope I have answered fully all of your questions and helped allay any fears you may have had.

Kind regards

New Threads

Forum statistics

Latest member