Adjustable Voltage Boondocker Converter Question
Do Randy's new adjustable boondocker converters have the initial 15 minute boost feature? thanxx!
Forum Discussion
I would be nervous about starting the PM3 or even a PM4 and then connecting it to the battery though. That is at least one factor in causing the in-rush thermistor to fail. They say that problem has been fixed in the newer models but I would still be nervous.
They are working on a new design that will not have an in-rush thermistor at all, but not there yet.
On cold start of a Honda and heavy load-- to run my 100amper, I have to start the Honda 3000 first and let it warm up before plugging in the charger or it will conk out if ambient is cold too. It warms up faster if you start it with eco-off. Plug in the charger with eco-still off and after the grunt, now you can put eco to on.
That is another way to blow the thermistor. The charger gets started before the Honda conks out and now you restart the Honda which restarts the charger, so you have a "hot restart" on the charger while its thermistor is still warm, so it fails.
The thermistor fails by having a crack through it but it keeps working, so you might not notice unless you have the lid off and look carefully. After a few hot restarts and more cracks in it, eventually it burns through and pieces fall off. At some point you will notice even with the lid on--see the smoke or the unit won't start.
Replacing the thermistor is fairly easy, but getting the board out takes a while unscrewing it all. You drill through the board from underneath where the thermistor RT1 legs go in the old solder, poke the new thermistor legs through, solder them a little above and below, and snip off the legs underneath. Pull on the thermistor to make sure it is not loose. Put the unit back together, say a prayer, and plug it in for a bench test.
They are working on a new design that will not have an in-rush thermistor at all, but not there yet.
On cold start of a Honda and heavy load-- to run my 100amper, I have to start the Honda 3000 first and let it warm up before plugging in the charger or it will conk out if ambient is cold too. It warms up faster if you start it with eco-off. Plug in the charger with eco-still off and after the grunt, now you can put eco to on.
That is another way to blow the thermistor. The charger gets started before the Honda conks out and now you restart the Honda which restarts the charger, so you have a "hot restart" on the charger while its thermistor is still warm, so it fails.
The thermistor fails by having a crack through it but it keeps working, so you might not notice unless you have the lid off and look carefully. After a few hot restarts and more cracks in it, eventually it burns through and pieces fall off. At some point you will notice even with the lid on--see the smoke or the unit won't start.
Replacing the thermistor is fairly easy, but getting the board out takes a while unscrewing it all. You drill through the board from underneath where the thermistor RT1 legs go in the old solder, poke the new thermistor legs through, solder them a little above and below, and snip off the legs underneath. Pull on the thermistor to make sure it is not loose. Put the unit back together, say a prayer, and plug it in for a bench test.
