Quote from: anwar on July 28, 2010, 08:05:20 PM
Buy a wattmeter and test on the ground.  Way to peace of mind/nirvana in leccies !

Hellow Anwar Sir, I got my wattmeter and i need some help. Kindly tell me what are the different readings and how are they useful? i was testing a turnigy aerodrive 42-60 sk series motor with 6s 4400 mah (two 3s 2200 in parallel), apc 12X6 E prop and 80 amp besc. the readings are as in pic below. how do i calculate thrust to weight ratio? and what about other readings. thx

CP, if you put 2 3S in parallel then your cells will become 3s 4400 mah and not 6s 4400 mah.

Here is what you should see:

Current:
1)Your 2200 batteries 20c in parallel can give you a maximum of 88 amps, but you should not draw more than 70 amps from it. Good for your batteries.
2)Your motor should not consume more than 70 amps with the prop.

Put your watt meter between the motor and batteries and chek to see if the amps are not more, amps indicated by A on your meter. Slowly increase throttle and see readings. Also make sure your ESC is getting good air flow. Check the temperature periodically.

Voltage:
It also shows how much the voltage drops when load increases.

WATTS:
It shows voltage x amps

AH:
It shows how much mah the motor has consumed from your battery since you started the experiment.

Connect watt meter properly. Connecting the battery to watt meter where you are supposed to connect motor will burn it.

Aaal da best!

You would need a spring balance setup etc to calculate thrust to weight ratio. Cant do that with a watt meter. You can see the trust by visiting hobbycity and reading user reviews for respective props.