The PULSE TRONIC system is TELWIN’s patented technology that is the brain of the T-CHARGE 20 charger. This is not a simple, linear charging process. It’s a dynamic, 8-step cycle that adapts to the individual needs of each battery.
The first step is ANALYSIS, where the charger checks the battery’s condition, voltage and ability to accept a charge. Then, if necessary, RECOVERY mode is activated, using current pulses to dissolve lead sulfate crystals on the plates, which often restores performance to older batteries. The main stage is BULK CHARGE, which is charging at maximum current until about 80% capacity is reached. This is followed by ABSORPTION CHARGE, where the current is gradually reduced and the voltage stabilized to fully and safely recharge the battery to 100%.
The next stages are ANALYSE (re-verification of charge maintenance), FLOAT (maintenance charging, compensating for self-discharge) and PULSE (special pulse maintenance mode for long-term maintenance of optimal condition). For the professional, this means the assurance that each battery, regardless of its type or degree of discharge, is treated individually, maximizing its life and performance, eliminating the risk of damage.

TELWIN T-CHARGE 20 is not only a charging, but also an advanced diagnostic and regeneration tool. Before the charging process begins, the device performs a preliminary analysis of the battery’s condition. A key function is RECOVERY, dedicated to batteries that have become sulfated due to deep discharge or long periods of non-use. T-CHARGE 20 sends precisely controlled high-voltage pulses that help break down the sulfate layer on the lead plates, restoring their active surface and energy storage capacity. Many times this saves a battery that would already appear to be due for replacement.
In addition, the T-CHARGE 20 offers test functions. It allows you to quickly check the battery’s charge level and, importantly for the mechanic, test the efficiency of the vehicle’s alternator. This makes it possible to quickly diagnose whether the problem with an undercharged battery lies with the battery itself or the car’s charging system. This comprehensive approach saves time and money, allowing for accurate diagnoses and effective repairs.

Working with batteries requires extreme caution, so the TELWIN T-CHARGE 20 is designed for maximum safety of the user, the battery and the vehicle’s electronics. The device is equipped with a number of protections: against reverse polarity (mistaken connection of clamps), against short-circuit (even if the clamps come into contact), against overload and overheating of the charger itself. Importantly, it is spark-free – it does not generate sparks when connecting or disconnecting clamps from the battery, which is crucial when working near fuel fumes.
The IP65 rating means that the housing is completely dustproof and protected from water jets from any direction. So you can use it in typical workshop conditions without worry. In addition, the “COLD” function allows you to optimize the charging process at low ambient temperatures (e.g. below 5°C). Under such conditions, the charging characteristics of lead-acid batteries change, and the T-CHARGE 20 adjusts the charging voltage to ensure a full and safe charge, even when there is frost outside the window. The “SUPPLY” function, on the other hand, is the ability to use the charger as a stable 12V/24V power source, such as when replacing the battery, preventing the settings of the on-board computer and other electronic systems in modern vehicles from resetting.