CTEK MXS 5.0 Faq page 7

Can I charge the battery without removing it from the
vehicle or opening the caps?
There is no reason to disconnect or remove the battery from the vehicle – or open the battery caps –
while charging with CTEK. CTEK chargers are spark proof reverse polarity protected and electronically
safe.
My charger never goes further than the float (first green)
level.
The charger stays in float maintenance mode for 10 days keeping the battery topped up
using the minimum level of current. After 10 days the program moves on to the last stage –
pulse level – for long term maintenance.
My charger gets very warm – is this normal?
Yes, this is normal when the charger is working hard in the bulk charge phase. The heat is
generated in certain circumstances depending on the battery that's being charged. The
charger does not necessarily heat up when it's charging other types of battery.
My charger will not start charging – is it broken?
CTEK chargers need some counter voltage to start providing tension/current. If there's a
poor connection between the charger and the battery charging will not start. If the battery is
below 2V charging will not start.
Can I charge Lithium batteries with a regular CTEK
charger and ordinary batteries with a Lithium charger?
No. Lithium batteries need a different type of charger to lead/acid batteries. We do not
recommend using a CTEK charger designed for lead/acid batteries. Charging lead/acid
batteries with a Lithium charger will not give the best results and cannot be recommended.
How should I connect the charger? My car has BMS
(Battery Management System)
Connect the red clamp (or eyelet) to the battery's positive (+) pole. You can connect the
black negative (-) clamp (or eyelet) to the chassis or a recommended earthing point.
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