A few people have asked me about the life (endurance) of the batteries in the H2, and I have replied I don't really know.
I do know a couple of things:
- The batteries became substantially depleted yesterday at NEEGOG, after perhaps two hours total running spread between there and at Albury and on test at home
- Charging back to full capacity yesterday evening took barely an hour
I suspect the capacity of the two-thirds AAA batteries is substantially less than the 400 mAh claimed by their manufacturer, simply because the recharging was so quick.
To keep the maths simple I will say the radio receiver/controller consumes 30 mA, and the loco motor averages 90 mA. These figures are about 10% high to keep my estimate conservative.
Suppose the loco runs constantly, like at NEEGOG
- The model consumes 30 + 90 = 120 mA
- Battey capacity appears to be around 240 not 400 mAh (because 2 hours x 120 mA = 240mAh)
Suppose the loco runs with a 1:5 duty cycle on my shunting layout
- The model consumes an average of 30 + ( 90 / 5 ) = 48 mA
- Battery endurance will be about 240 / 48 = 5 hours
Suppose I leave the loco switched on and forget about it
- The model consumes an average of 30 mA
- Battery endurance will be about 240 / 30 = 8 hours
Five hours is less useful than the seven hours I predicted, but the one-hour recharge could be helpful. I need at least one more locomotive to provide cover if I want to operate for a seven-hour show, but the railway does now have access to six more locos apart from this one!
The Micron MR603 receiver offers a substantially reduced power consumption over the MR601 I used here because the board is large enough to hold a more sophisticated power regulator. I had to choose the smaller receiver to fit it into the model.
Maybe this is useful to someone, though I don't know whether the people who asked me are on WT.
