The CTEK Smartpass is a power management device.
This clever ‘black-box’ maximizes the utilization of alternator, solar and AC/DC charging devices, while protecting the house or service battery from over discharge.
A common problem, especially with caravans and motorhomes equipped with three way fridges (gas, DC and AC) is trying to charge a house battery, from the vehicles alternator, whilst still running the fridge. Some three way fridges can draw up to 25 amps, so we have a situation where we are trying to quickly and efficiently charge a battery, while, at the same time, we are drawing power from it to run the fridge! The end result is usually a very under-charged battery with poor performance and service life.
The smartpass gets around this problem by supplying power to the user loads, directly from the alternator, while the vehicle is running. This enables the house battery to achieve full charge without supplying loads at the same time. When the vehicle is switched off, the smartpass then switches the loads to the house battery. A battery watch feature ensures that the house battery is not over discharged and damaged. Very clever!!!.
Of course modern vehicle alternators do not efficiently charge house deep cycle batteries, so the smartpass is designed to work ‘hand in hand’ with the CTEK D250 Dual DC-DC Charger (see separate blog).