it says "Automatic" - I wonder if it might think the battery is done charged & it might shut down while using ?
if not, I think it would be ok to use. I'd try it 15 amps & see if it gets too warm (charger) in a couple hours. I bet it don't but if so, go to 2 amp.
when mine, I've checked my amps to the relic & usually only a few amps, if even that
my 2¢