If you measure 10 volts AC from a 24 volt DC power supply, what might this indicate?

Measuring 10 volts AC from a 24 volt DC power supply typically indicates that there is an issue with the power supply, making it likely that the filter capacitors are bad. A properly functioning DC power supply should output a clean, stable DC voltage with little to no AC ripple. The presence of an AC voltage reading suggests that there may be insufficient filtering of the ripple voltage, often due to degraded or failed filter capacitors which are responsible for smoothing out the output voltage.

If the filter capacitors in the power supply are damaged, they may not be effectively filtering out the AC component of the voltage, allowing a measurable AC ripple to appear in the output. This could lead to unstable operation of any devices powered by the supply, making it important to identify and address this issue as part of regular maintenance and troubleshooting processes.