G-13 Coin Dispenser Incorrect Change Troubleshooting -... | terminalfaults.org

Technical Background:

Coin dispensing mechanisms typically utilize a 24V DC solenoid-driven system to release specific coin denominations. An embedded microcontroller, monitoring optical or inductive sensors, controls the solenoid activation duration. Incorrect dispensing can stem from voltage fluctuations impacting solenoid operation, sensor miscalibration due to environmental factors, or mechanical obstruction within the coin path. Environmental temperature variations can affect sensor accuracy and solenoid response times. Solenoid coil resistance changes with temperature, impacting holding force and release speed.

Symptoms:

The G-13 coin dispenser accepts coin input but dispenses incorrect (less than expected) change to the customer.

Possible Causes:

Low or fluctuating 24V DC power supply voltage affecting solenoid actuation strength and timing.
Optical sensor contamination (dust, debris) causing inaccurate coin detection and dispensing counts.
Mechanical obstruction (foreign objects, coin debris) in the coin dispensing path hindering proper coin release.
Solenoid coil degradation leading to reduced magnetic force and unreliable coin release.
Corrosion on electrical connectors causing increased resistance and reduced voltage to the solenoids.
Firmware error or corruption in the embedded controller affecting dispensing logic.

Solution:

1

Initiate system diagnostic mode (refer to the G-13 service manual) to access error logs and diagnostic tests.
2

Verify the 24V DC power supply output using a calibrated multimeter. Ensure it meets the specified voltage and current requirements under load (dispensing coins).
3

Visually inspect the coin dispensing path for any obstructions (foreign objects, deformed coins). Use compressed air to remove loose debris.
4

Clean the optical sensors using a dry, lint-free cloth. Avoid using liquids, which can damage the sensor.
5

Check the electrical connectors for corrosion or loose connections. Gently reseat connectors and clean corroded contacts with an appropriate electrical contact cleaner.
6

Cycle power to the G-13 system to reset the embedded controller and clear any transient errors.
7

If issues persist, attempt to re-flash the coin dispensing firmware using the manufacturer-provided update utility and ensure the correct version is installed.

Safety Warning:

This kiosk contains electrical components operating at 24V DC, presenting a potential electrical shock hazard. Before performing any maintenance, disconnect the kiosk from the main power supply and follow all Lockout/Tagout (LOTO) procedures to ensure the power cannot be inadvertently restored. Use extreme caution when handling electrical components, especially in damp or wet conditions. Environmental conditions can affect the operation of this device. This is an unattended, public kiosk. Any repairs must maintain the vandal-proof enclosure.

Prevention:

Implement a regular cleaning schedule for the coin dispensing mechanism, including the coin path and optical sensors (frequency depends on environmental conditions).,Install a surge protector on the power supply line to protect against voltage spikes and fluctuations.,Periodically inspect electrical connectors for corrosion and ensure they are properly seated.,Implement a preventative maintenance schedule that includes sensor calibration if the G-13 service manual provides those tools.,Ensure the kiosk environment is climate controlled to minimize temperature fluctuations which can affect sensor accuracy.

Expert Tip:

Erratic solenoid behaviour can sometimes be attributed to electromagnetic interference (EMI). Installing a ferrite choke on the 24V DC power cable near the coin dispenser can mitigate EMI-related issues.

Frequently Asked Questions

•What are the specified voltage and current requirements for the G-13's 24V DC power supply?

Refer to the G-13 service manual for the exact voltage and current specifications. Typically, it will be 24V DC +/- 10% with a current rating of at least 5 Amps.

•What type of electrical contact cleaner is recommended for cleaning corroded connectors?

Use a non-residue electrical contact cleaner specifically designed for electronic components. Ensure the cleaner is safe for use on plastics and rubber.

•Where can I find the G-13 service manual and firmware update utility?

Contact the manufacturer or authorized distributor of the G-13 coin dispenser. They can provide access to the service manual, firmware updates, and any necessary diagnostic tools.

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•What are the specified voltage and current requirements for the G-13's 24V DC power supply?

•What type of electrical contact cleaner is recommended for cleaning corroded connectors?

•Where can I find the G-13 service manual and firmware update utility?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: