Using a 12V AC power supply on a device that is designed to run on 9V AC can be risky and potentially damaging to the device. It is not recommended to use a power supply with a higher voltage rating than the device's specified requirement.
Here's why:
Voltage Difference: The device is designed to operate at a specific voltage (in this case, 9V AC). Applying a higher voltage (12V AC) than the device's intended voltage can cause the device to draw excessive current, potentially overheating and damaging internal components.
Potential Damage: The device's circuitry may not be designed to handle the higher voltage, and sensitive electronic components, such as integrated circuits or transformers, may fail when subjected to the increased voltage.
Safety Concerns: Using a power supply with higher voltage than required can pose safety hazards. There might be a risk of electrical arcing, short-circuiting, or fire if the device's components cannot handle the excess voltage.
To ensure proper and safe operation, always use a power supply that matches the device's specified voltage requirements. In this case, you should look for a 9V AC power supply with an appropriate current rating that meets or exceeds the device's power consumption needs. Using the correct voltage power supply will help protect the device and ensure its proper functionality. If you are unsure about the appropriate power supply, consult the device's user manual or contact the manufacturer for guidance.