Understanding CTEK Charge Curves

 

What happens inside a CTEK charger when you connect it to your battery?

A charge curve is the sequence of charging stages a charger follows to analyse, charge and maintain a battery. CTEK's intelligent multi-stage charging technology is designed to optimise battery performance, extend battery life and ensure reliable power when you need it most.

Explore the different CTEK charge curves to see how each stage works to charge, condition and maintain your battery for maximum performance and longevity. 

 

6-Stage Charging

Featured in our XS 0.8 charger.

CTEK's 6-stage charge curve is designed to recondition, charge and maintain your battery for optimum performance and longevity.

CTEK XS 0.8 Charging StagesXS 0.8 - CHARGING PROGRAM

A 6-stage charger (no soft start or recond as amperage output 0.8 A is too low).

STEP 1 DESULPHATION

Detects sulphated batteries. Pulsing current and voltage, removes sulphate from the lead plates of the battery restoring the battery capacity.

STEP 2 BULK

Charging with maximum current until approximately 80% battery capacity.

STEP 3 ABSORPTION

Charging with declining current to maximize up to 100% battery capacity.

STEP 4 ANALYSE

Tests if the battery can hold charge. Batteries that cannot hold charge may need to be replaced.

STEP 5 FLOAT

Maintaining the battery voltage at maximum level by providing a constant voltage charge. 

STEP 6 PULSE

Maintaining the battery at 95–100% capacity. The charger monitors the battery voltage and gives a pulse when necessary to keep the battery fully charged.


7-Stage Charging

Featured in our MXS 3.8 charger.

Building on the 6-stage charging process, CTEK's 7-stage charge curve adds an intelligent ANALYSE stage. This additional step checks whether the battery can accept and retain charge, helping to identify batteries that may be nearing the end of their service life.

CTEK MXS 3.8 Charging StagesMXS 3.8 - CHARGING PROGRAM

A 7-stage charger (no recond).

STEP 1 DESULPHATION

Detects sulphated batteries. Pulsing current and voltage, removes sulphate from the lead plates of the battery restoring the battery capacity.

STEP 2 SOFT START

Tests if the battery can accept charge. This step prevents that charging proceeds with a defect battery.

STEP 3 BULK

Charging with maximum current until approximately 80% battery capacity. 

STEP 4 ABSORPTION

Charging with declining current to maximize up to 100% battery capacity.

STEP 5 ANALYSE

Tests if the battery can hold charge. Batteries that cannot hold charge may need to be replaced.

STEP 6 FLOAT

Maintaining the battery voltage at maximum level by providing a constant voltage charge. 

STEP 7 PULSE

Maintaining the battery at 95–100% capacity. The charger monitors the battery volt-age and gives a pulse when necessary to keep the battery fully charged.


8-Stage Charging

Featured in our MXS 5.0, MXS 5.0 POLAR, MXS 7.0 & MXS 10 chargers.

CTEK's 8-stage charge curve delivers the ultimate in battery care by recovering, charging, analysing and maintaining your battery. In addition to charging and maintenance, the advanced process includes battery health checks and a dedicated RECOND stage that can help restore deeply discharged batteries and recover lost capacity.

CTEK MXS 5.0 Charging StagesMXS 5.0 - CHARGING PROGRAM

Full 8-stage algorithm.

STEP 1 DESULPHATION

Detects sulphated batteries. Pulsing current and voltage, removes sulphate from the lead plates of the battery restoring the battery capacity.

STEP 2 SOFT START 

Tests if the battery can accept charge. This step prevents that charging proceeds with a defect battery.

STEP 3 BULK

Charging with maximum current until approximately 80% battery capacity. 

STEP 4 ABSORPTION

Charging with declining current to maximize up to 100% battery capacity.

STEP 5 ANALYSE

Tests if the battery can hold charge. Batteries that cannot hold charge may need to be replaced.

STEP 6 RECOND

Choose the Recond program to add the Recond step to the charging process. During the Recond step voltage increases to create controlled gassing in the battery. Gasing mixes the battery acid and gives back energy to the battery. 

STEP 7 FLOAT

Maintaining the battery voltage at maximum level by providing a constant voltage charge. 

STEP 8 PULSE

Maintaining the battery at 95–100% capacity. The charger monitors the battery voltage and gives a pulse when necessary to keep the battery fully charged.


CTEK MXS 7.0 & 10 Charging StagesMXS 7.0 & 10 - CHARGING PROGRAM

STEP 1 DESULPHATION

Detects sulphated batteries. Pulsing current and voltage, removes sulphate from the lead plates of the battery restoring the battery capacity.

STEP 2 SOFT START

Tests if the battery can accept charge. This step prevents that charging proceeds with a defect battery.

STEP 3 BULK

Charging with maximum current until approximately 80% battery capacity. 

STEP 4 ABSORPTION

Charging with declining current to maximize up to 100% battery capacity.

STEP 5 ANALYSE

Tests if the battery can hold charge. Batteries that cannot hold charge may need to be replaced.

STEP 6 RECOND

Choose the Recond program to add the Recond step to the charging process. During the Recond step voltage increases to create controlled gasing in the battery. Gasing mixes the battery acid and gives back energy to the battery. 

STEP 7 FLOAT

Maintaining the battery voltage at maximum level by providing a constant voltage charge. 

STEP 8 PULSE

Maintaining the battery at 95–100% capacity. The charger monitors the battery voltage and gives a pulse when necessary to keep the battery fully charged.


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