Using CellPro 4S as a watt meter?

[Ellis]

I guess this is probably for flydiver,
I have a CellPro 4s charger and I think I read that you (fly) used it as a watt meter. If so could you tell me how it's done. It's not covered it the instructions.
Ellis

[flydiver]

No, can't use it as a wattmeter. It will give you individual cell voltages and % of battery capacity remaining, neither of which a wattmeter will give you. This can be useful at the field if you are trying to figure out how long you can run batteries in a particular plane. I time my flights so have not seen LVC in months.
Wattmeter will only give you resting total voltage if merely used as a 'voltmeter'. Of course a wattmeter does a WHOLE lot more. I use both tools all the time.

There is a charger that has a wattmeter type of device sort of built in I think. Pretty expensive and don't recall the name right now. Got an X prominent in the name I think.

fly

[Ellis]

Thanks fly,
I was just thinking of learning more about the power consumption and prop ratios, but I guess it wont be tonight.

By the way, did you look at this software download?
www.toddsmodels.com/Scorpion_Calc_Software_Available_for_Download_s/148.htm

Ellis

[flydiver]

I've looked at similar [Motorcalc] but don't use it. There are just so many variables that I like the solid evidence of testing what I am actually going to use. Generally I check motor manuf. recommendations, decrease it by 20% and start from there. Most of the data is pretty much a fantasy even some of the better motors and almost all of the Chinese.

I still have a buddy that's fixated on slow fly props and over propping. "But I only fly at 1/2 throttle and I want the power to get out of trouble". Can't convince him that all he is seeing at the upper end of the wattmeter reading on an overpropped motor is HEAT-not more power. Heat is measured in watts too. The wattmeter doesn't tell the WHOLE story but it sure helps shed some light on the darkness.

The other tools to be more complete are a Tachometer, an infrared thermometer, and a thrust stand. I haven't gone the thrust stand route-I just fly 'em and see what I like after I'm sure I'm not burning them up.

I've just gotten into rewinding motors and that is a bit of an eye opener.

fly