Troubleshooting 'Invalid Input' errors on unattended kiosks. Focus on environmental resilience, polymer bill calibration, and non-invasive diagnostics.
Excessive heat or cold can affect sensor accuracy.
Knowing the specific bills being rejected can help isolate the problem.
Physical damage can affect the bill validator's operation.
Bill validators in unattended kiosks typically use a 24V DC power supply to energize solenoids for bill transport and optical sensors to analyze bill characteristics (size, reflectivity, and security features). Polymer bills, weather fluctuations, and mechanical wear can affect sensor accuracy and solenoid operation. Signal attenuation due to damaged cables or connectors can also disrupt communication between the validator and the kiosk's central processing unit.
The kiosk displays an 'Invalid Input' error message when attempting to validate bills.
The kiosk operates on 24V DC power, but the power supply may handle higher voltages. Ensure the kiosk is de-energized using Lockout/Tagout (LOTO) procedures before performing any maintenance or troubleshooting. If working near external power, ensure the area is dry and use insulated tools. Avoid contact with internal components unless properly trained and qualified.
Implement a regular maintenance schedule that includes cleaning the bill validator's input slot and surrounding areas with compressed air. Periodically inspect cable connections for tightness and corrosion. Ensure that the kiosk environment is protected from extreme temperature fluctuations and humidity. Regularly update the kiosk and bill validator software to the latest versions.
Environmental factors such as extreme cold can impact sensor performance. If the kiosk is located in a region with frequent sub-zero temperatures, consider using a validator equipped with a heater or a climate-controlled enclosure to maintain optimal operating temperature. If the unit supports bill-by-bill acceptance logs, cross-reference timestamps of 'Invalid Input' errors with weather logs.