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Electric Stunt => Gettin all AMP'ed up! => Topic started by: Keith Miller on September 24, 2016, 03:59:28 PM
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Hi all -
Any ideas would be appreciated. ???
Here's the issue. About 50% of the time, the system will start up (after the initial "burp"), spool up (with some bit of what sounds like hesitation), then shut off between 1 and 4 seconds later. In some cases the motor never comes up to full speed, in others it will quit just a second or two after reaching full speed.
Thanks in advance! H^^
Motor: Turnigy Aerodrive SK3-2836-150 with 8x5e prop
Battery: A-SPEC 1.8 mAh 3-cell
Set RPM 10,554 (achieving only 9800 actual but not at a voltage or current limit)
Current draw - 16.8 A peak / 181 Watts.
Minimum pack voltage observed - 10.7 V under full load
Suspecting bad cells, I swapped batteries; all are new and perfectly balanced.
I monitored the individual cells and never saw voltages drop below about 3.5.
I thought maybe the ESC to timer connector was loose, but it's snug.
Timer settings:
2 min run, 5 sec delay, ESC Mode: Phoenix new high 10,554 RPM
Here's the Talon settings:
Auto Rotate Enabled: False
Auto-Lipo Volts/Cell: 3.2 Volts/Cell (*)
Brake Delay: .6 sec (Delayed) (*)
Brake Ramp: Immediate (*)
Brake Strength: 50% (Soft)
Current Cutoff Type: Soft Cutoff (*)
Current Limiting: Very Sensitive
Cutoff Voltage: Auto Li-Po (*)
Desired Head Speed 1: Optional
Desired Head Speed 2: Optional
Desired Head Speed 3: Optional
Direction: Forward (*)
Governor Gain: 40
Governor Mode Type: High
Head Speed Change Rate: 6
Hex55: 85
Initial Spool-Up Rate: 10
Link Live Enable: Disabled (*)
Motor Start Power: Medium (59) (*)
Motor Timing: Normal (5) (*)
Power-On Beep: Enabled (*)
PWM Rate: 12 Khz (*)
Throttle Response: Medium (5) (*)
Throttle Type: Governor Mode
Vehicle Setup - Gear Ratio: 1.000
Vehicle Setup - Motor Kv: 1500
Vehicle Setup - Motor Number of Poles: 14
Vehicle Type: Control Line
Voltage Cutoff Type: Soft Cutoff (*)
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Keith,
Firstly, the Talon 35's actual rpm is always way below the setpoint, so I don't think that's an issue with your problem. My guess is that the "very sensitive" current limiting setting is the problem. Set it to "normal" or "insensitive" and see if the problem goes away.
Rick
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The times mine acted that way was when I was trying higher rpm set ups so maybe you're over current? Try a prop with more pitch and less rpm.
MM
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Keith,
Firstly, the Talon 35's actual rpm is always way below the setpoint, so I don't think that's an issue with your problem. My guess is that the "very sensitive" current limiting setting is the problem. Set it to "normal" or "insensitive" and see if the problem goes away.
Rick
Thanks, Rick. Copy on the RPM setpoint.
Do you suppose that, given a certain governor gain, that the ECS is causing some short-duration current spikes that the "very sensitive" current limit is picking up?
I'll try "normal" sensitivity.
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I had the same RPM issue using the turnigy motors - they weren't up to it. Swapped to Scorpion and all the issues went away - hit RPM as programmed etc