I have the above mentioned DC-DC charger installed in a camping trailer (tiny pod caravan) with 12V coming from the car through the towing electrics.
The problem I am having is that it is causing issues with the car's electrics with the inrush current at initial charge start. The car's constant 12V is fed off the main wiring loom with a 15A fuse although the fusebox can supply up to 60A total so the first I noticed an issue was that the 15A blew. When I installed a bigger fuse to test I got the charger to work again but it's causing the following problem...
When the charger sees the car start with alternator sensing it engages the charge and with a clamp meter on the input cabling goes to about 42A. This massive current draw drags the input voltage down to about 8V where the charger automatically cuts out. Once the voltage rises it cuts back in and keeps repeating.
If I disable the alternator sensing or adjust the cutout voltages, the initial spike of 40+ amps on the input settles down to a more agreeable 10A and the input voltage holds steady at around 13.5V. I'd rather not have the alternator sense disabled though.
Does anyone have any suggestions of what I can do to reduce the inrush current or at least set the charger in such away that it doesn't cut out during the initial spike so that it can settle down to 10A before it wants to cut out?
