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esc amperage

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Old 09-12-2022, 04:35 PM
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Default esc amperage

if a motor suggests a 70~80 amp esc, can I use a 60amp?
Old 09-13-2022, 12:31 AM
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Cecil Webb
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No. You should not use it. If so, it will burn up the ESC.
Usually you should use ESC equivalent or greater than motor requirements.
Old 09-15-2022, 12:46 AM
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Originally Posted by [email protected]
if a motor suggests a 70~80 amp ...
Isn't that just he motor's maximum current rating? Or specifically an ESC rating advice?

Note that motors can handle any voltage, as long as rpm, actual current and actual power don't get too high.
The winding wire insulation/lacquer/resin can handle several hundred volt.

Originally Posted by [email protected]
... can I use a 60amp?
Yes. But only if you prop-load and voltage the motor to draw that current at wide open throttle (WOT).
Current drawn is proportional to pitch, voltage² Name:  eek.gif
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All in all massively disproportional effects!
Some scary, some expensive realistic Name:  frown.gif
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Therefore always measure current in a new or changed power system.
A watt-meter will pay for itself, several times over, bigly.

Last edited by ron_van_sommeren; 09-15-2022 at 12:52 AM.
Old 09-15-2022, 12:46 AM
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Another thing to take into account ...
Power system derating
It is a good practice to have some headroom built in. Motor runs cooler, slightly more efficient too, and you have some leeway should things go south a bit.
About derating motors, controllers, batteries, electronics in general:
Vriendelijke groeten Ron
• Without a watt-meter you're in the dark ... until something starts to glow •
E-flight calculatorswatt-metersdiy motor tips&tricksCumulus MFC
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Old 09-16-2022, 05:08 AM
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Using a controller with a higher voltage and/or current rating is not a problem.
That only carries a mass and size 'penalty'.

A controller does not 'force feed' the motor with current.
Only pitch, voltage², Kv³ & gearing³ and prop-diameter⁴ determine actual current, as described earlier in post_#3 above.

The rules are almost the same for power drawn, voltage excepted.
Power is drawn is proportional to voltage³.

At full throttle the controller his little/no effect on current and power drawn, it just passes on what the power system demands, even if it would lead to its fiery death.

Prettig weekend Ron

Last edited by ron_van_sommeren; 09-16-2022 at 05:11 AM.
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