Is it possible to trigger a 24VDC fluid solenoid via Arduino Uno w/ Adafruit Motor Shield? I have heard they can only handle 12VDC.
The manufacturer’s datasheet for the device (TB6612) quotes 15v as the absolute maximum for the motor voltage, so it would be unwise to run it at anything above 12v. In any case, that device is not suitable for driving a solenoid. A relay or high-current MOSFET module would be a better choice.
OK, got it that 24VDC exceeds capabilities, but for driving solenoids there is this: Controlling a Solenoid with an Arduino - Tutorial Australia
I built a motion model based on this with the Uno/Adafruit driving two 12v Norgren air solenoids, haven’t encountered a problem. Yet.
A simple solution would be a little Freetronics board with a N channel Mosfet on it. Stocked by Core SKU: CEO 4538.
Connect Motor supply (24V) to motor +
Connect Source (S) to common ground
Connect Drain (D) to motor -
Connect Gate (G) directly to Arduino Digital I/O pin
Connect fast diode across motor, Cathode (K) to +ve motor supply. DO NOT FORGET THIS. “Normal” power diode may not be fast enough and must be rated to at least the operating current of the solenoid.
The power transistor used in that tutorial is essentially the same as a MOSFET module, except that the MOSFET is more efficient, and, in the form of a pre-configured module, is much simpler to use. The motor driver is designed for pulsed operation and would likely burn out if required to hold a solenoid in for any extended period.