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Strange error with actuators powered by same power supply

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Stargate30

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What I have:
I am using a Teensy 3.2 microcontroller to operate 3 actuators. They are all 0-10VDC signal, and 0-24VAC power.
I am using a 24VDC power supply with a voltage divider to create a 10VDC rail on a breadboard.
Each of the actuators has its own MOSFET, which controls the exact signal voltage that each on gets. The Teensy's PWMs are connected to the FET gates. The sources go to GND, and the drains are connected to the negative side of the signals. The positive side of the signals are on the 10VDC rail.
When I provide power to each one individually, they have full range of motion.
Additionally, when I command a different duty to each one, the voltage drop across the signal wires for each one is different, and the same when the same duties. This makes sense, and shows that the FETs work.

The problem:
I have two 24VAC power supplies. When more than one actuator is connected to a single supply, both of the signal wires assume the same, larger voltage. The PWMs coming from the Teensy are still correct (and different), but the voltage drop across the signals for the "paired" actuators become the same. Both power supplies produce this result and any combination of two actuators also produces the same result.
This is strange to me because the power supply is affecting the signal, which aren't connected anywhere, and are likely isolated in the actuators themselves.
Additionally, last year, in a different setup but same connections between the supplies and actuators, there was independent movement by all three actuators.

Thoughts?
 

Reloadron

Well-Known Member
Most Helpful Member
I am using a 24VDC power supply with a voltage divider to create a 10VDC rail on a breadboard.
A schematic or drawing would help considerably. Looking at the above quote I don't understand how you can do this? Anything in parallel with any of your divider resistors (the load) will change the divider ratio.

Ron
 

dr pepper

Well-Known Member
Most Helpful Member
Something I dont get is the fact you mention fets and then later an ac supply, a single fet can only switch dc.
We need a schem, a hand drawn and scanned one is fine.
 

ci139

Active Member

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