Avoid sparks and contact current surge!

When connecting a battery to a load with a capacitive input for the first time, a connection current surge / arcing occurs when the load capacity is charged to the battery voltage.
With large batteries (with low internal resistance, especially lithium batteries) and heavy loads (with large capacitors at the input / output), the contact current surge can easily reach 1000 A.

It "sparks" when connecting. This is not ideal for the service life of the capacitors and batteries, and contact burn-off can also occur at the contact point. This material burn-off can lead to injuries (eyes) and damages the connection point. This is particularly the case with large inverters & chargers above 24V.


To avoid this contact / connection current surge, the device should be "pre-charged" via a resistor before connection to the battery.


With the pre-charge / pre-charge cable, we have created a pre-charge resistor with which sparking and the contact current surge can be avoided.


This pre-charge resistor is not intended for pre-charging with main switches.
If you want to pre-charge with a main switch, this must be permanently installed via a button.
Pre-charge units are available for automatic main switches. Please contact us for more information.