Well ... it might be a few milliamps, since my built in three-place ammeter can only resolve around +/- 100 milliamps. However, as I've noted, jacking the charge voltage up via the alternator still finds the ammeter saying "zero".
The DCS-100HIT model from this spec sheet is the latest version of what I think Interstate relabeled and sold me two of way back in 2006. Note the recommended float voltages that are perfect for a stock converter. Also note the "Equalization and Cycle Service Charging and Current Limits" are just that - limits - not requirements. My batteries almost never see more than 14.4 volts - so I guess their cells may not be very equal after nearly 8 years. I do still see it sitting around 12.84 volts after arriving at full charge:
http://www.cdtechno.com/pdf/lit/12_1061_10.pdf