jtaylor wrote:

Got a diesel, and it gets cold here. There's a block heater, but I also
have a 1A charger that could be attached to the same extension cord - would
there be any drawback/problems with leaving this connected (on the battery
side) _all_ the time? It's a cheapo transformer & diode unit.

There's a wonderful product called "Battery Tender". Many guys who own large
motorcycles own them. It's like a wall wart but it comes with lots of different
connector types including lugs, battery clamps, etc. I have a power outlet on my
bike which is designed for connecting power to heated riding clothing, said
outlet which is always connected to the battery. It's ideal for plugging in a
battery tender. Many vehicles have lighter sockets which aren't switched off
when the key is off, these are also excellent ways to trickle charge a battery.
They aren't cheap at around $50 but they work perfectly and seem to last
forever. There are indeed problems with a trickle charger being left on - if you
force current into a charged battery you will just dry out the electrolyte and
damage your battery.

GWE