April Propwash 2018 web.pub

water is determined by those other factors (small prop vs. larger prop), but either way, performance potential is determined by the available power. The following data represents the 4 of the most popular, currently allowed P-LTD Motors: AQ1800 AQ2030 DYNM1500 DYNM1800 I will expect to compare all the other motors to these. For these tests, I did the following: 1. Battery: 4S2P ThunderPower 70C 5000mAh packs (Total 10,000mAh), fully charged prior to each test run and allowed to return to "normalized" temperature before each test. 2. Battery's were paralleled in order to attempt to maintain 15.0V +/-0.2V for the entire 60-second pull. 3. ESC: Castle Hydra Edge 100 with water cooling on to maintain a consistent ESC temperature. 4. Load: Loads were applied using various arrangements of airplane propellers to achieve a ~100A, hopefully within +/- 5.0A, load. 5. Temp: Temperature was monitored using a Spektrum DX-9 with AR400 RX and TM1000 Telemetry module, using a band style temp probe (normally used for wrapping around a cylinder head or exhaust tuned pipe). 6. Temperature was recorded within 1/4" of the forward end bell by taping the probe to each motor in exactly the same manner. 7. Temperature was recorded prior to each run, and again after each run, once it had climbed to its maximum, determined by the point where it no longer increased (Absolute maximum recorded). 8. VOLTAGE, MAX RPM, WATTS, and AMPS, were taken as an average over the course of a minimum of 40-seconds, starting approximately 10-seconds after the start of each run. Starting point is determined based on the point on the graph where the values are stabilized. The motor initially loads up and then tapers down to a steady state, generally after about 5-10 seconds at full throttle. 9. I will consider this data to be baseline by which every other motor will be compared. Once a complete data set is available, a more direct comparison of these motors should be possible. There is quite a KV drop for those four motors because it’s quite a massive load. The KV drop is REAL KV (explained above) minus the resulting calculated KV. The more efficient/ powerful the motor, the less KV drop you'll see. Some indicators to look at are going to be KV Drop, Temperature Delta, and resulting maximum RPM. A more efficient, more powerful motor should provide more KV and should probably have less temperature gain over the test time. However, that could be skewed by the motor construction. It's possible for a motor to be powerful, but heat up due to the materials/mass of the motor. I tested the following 3650 motors: TP 3650-1970 LPB 3650-1840 Neu 1410-2Y SSS3650-1500 I used the same test parameters as described above. Physically, these motors are representative of the actual rotor/ stator size to our present P-limited motors. However, being 4- Pole vs. 6-Pole, they have less torque, and therefore don't appear to handle the 90-100 amp currents well. One motor finally bit the dust as well. The SSS3650-1500 motor started Test #1: NO LOAD Purpose: To determine the real KV for each motor. Note: The idle current from this test could provide insight as to motor efficiency, but in many cases was too low to be recorded, so I'm ignoring it for now. I did a series of tests with fixed prop loads. Based on that data, I'm going to vary the loads on each motor in order to test each at a load at or very near 100 amps. I'm going to run these for a much longer period of time, measuring the temperature before and after the run. I will be paralleling the batteries in order to provide a more stable voltage supply (Sorry, I wish I had a high-amp variable power supply, but those are really expensive, so batteries will have to suffice). The goal will be so try to record 60-seconds of data for each motor, with starting/ending temps, etc. Ultimately, this will tell us which motors are equivalent and which are clearly outside of the present P-limited performance range. Based on the data thus far, it's pretty clear which motors currently appear to exceed the present performance levels. More data will make clear exactly where each stands. Why do I need to test each motor at 100 amps? My goal is to measure the motors ability to produce power. Power... Watts... Horsepower... is determined by Voltage and Current (P = Voltage x Current). By getting each motor to 100 amps and attempting to maintain a similar voltage under load, each motor is putting out the same power. From there, heat build-up, KV drop, and maximum RPMs, can then be more directly compared. Ultimately, speed is determined by power available, regardless of the KV or RPMs. How you put that power to the PROPWASH Page 20 April 2018 Test Setup Test #1 results