Thread Tools
May 24, 2015, 10:16 PM
Closed Account
Thread OP
Discussion

OPTO ESC Receiver Input Voltage???


Hi all,

I purchased the following OPTO ESC:

http://www.altitudehobbies.com/ztw-g...ice&order=DESC

However, the manual does not specify the input voltage for the ESC signal. Is it safe to assume its the standard 5V?
Sign up now
to remove ads between posts
May 25, 2015, 02:54 AM
Registered User
It's safe to assume that the throttle signal requirement of an opto ESC is the same as for any other ESC.

What is different about an opto ESC is that it doesn't provide any power to the receiver because it doesn't have a BEC built into it. So you need to provide 5v (or thereabouts) power to the receiver from another source, such as a regular receiver battery or a stand-alone BEC.
May 25, 2015, 05:55 AM
Closed Account
Thread OP
Thanks, abenn. So then the receiver provides +5V, ground, and PWM signal?
May 25, 2015, 06:13 AM
Registered User
Yes, the receiver supplies whatever voltage you feed it (usually around 5V), ground, and PWM signal to the opto ESC.
May 25, 2015, 08:13 AM
homo ludens modellisticus
Ron van Sommeren's Avatar
With opto, the only link between receiver and controller electronics is via light, via the optocoupler. The plus and minus in the servo lead only feed the light-emitting-diode in the opto-coupler, not connected to the rest of the controller. Thus the high and low power circuits are isolated.

Quote:
Originally Posted by Lnagel
Opto means there is optical rather than electronic coupling between the low voltage, low current control signal from the receiver to the ESC and the high voltage, high current from the ESC to the motor. This electrically isolates the high voltage and low voltage portions of the ESC to minimize interferance. With no direct electrical coupling between the high voltage and low voltage circuits noise generated by the motor cannot feedback to the low voltage control signal. The fact that there is no BEC is a consequence of this type of coupling rather than the purpose. Larry
Planar (top) and silicone dome (bottom) layouts - cross-section through a standard dual in-line package.
Relative sizes of LED (red) and sensor (green) are exaggerated.



Vriendelijke groeten Ron
Last edited by Ron van Sommeren; Jun 24, 2015 at 06:10 AM.
May 25, 2015, 10:43 AM
Registered User
Quote:
Originally Posted by Ron van Sommeren
With opto, the only link between receiver and controller electronics is via light, via the optocoupler. The plus and minus in the servo only feed the light-emitting-diode in the coupler, not connected to the rest of the controller. . . .
Unfortunately there are several examples of ESCs which are described as "opto" but don't have any optocoupler -- some Far Eastern companies use the term to mean "no BEC"

Anyway, that doesn't affect my answers to the OP.
May 26, 2015, 09:20 PM
Retired Electronics Specialist
vollrathd's Avatar
Quote:
Originally Posted by lordvon
Hi all,

I purchased the following OPTO ESC:

http://www.altitudehobbies.com/ztw-g...ice&order=DESC

However, the manual does not specify the input voltage for the ESC signal. Is it safe to assume its the standard 5V?
A number of the higher powered ESC's use optical coupling between the receiver throttle output and the ESC. One big advantage of that is reduction of electrical noise from the ESC affecting the receiver. That's much less of a problem with the 2.4 Ghz radios commonly used now days. Add to that, high voltage ESC's often use split battery packs. An isolated ESC can prevent disaster if the negative wires of the ESC, two battery packs and the receiver ever get criss crossed.

Opto Couplers work from a volt or to up to 5 Volts DC. Depending on receiver type, some receivers put out 3 Volt DC pulses. They also work just fine.


Quick Reply
Message:

Thread Tools