THS-5212 Troubleshooting Guide

Please follow the steps below in order.

Safety Warning: Always disconnect the machine from the power supply before removing components, changing wiring, or moving relays. Electrical troubleshooting should be performed carefully and preferably by qualified personnel.

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Step 1 — Check the Lower Limit Switch

1. Disconnect the machine from the power supply.

2. Remove the lower limit switch.

3. The first possible cause is a failed lower limit switch. To test it:

   • Move the wire from terminal “0” to terminal “NC.”

   • Connect the two wires together to temporarily bypass the lower limit switch.

4. Reconnect the power and turn on the machine.

5. Test the machine using the foot pedal.

   • If the foot pedal works normally, the lower limit switch is faulty and should be replaced.

   • If the machine still does not work, proceed to Step 2.

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Step 2 — Check the Delay Switch

1. Disconnect the machine from the power supply again.

2. Move the wire from terminal “5” to terminal “3.”

3. Connect the two wires together at the same terminal point.

4. The circled white delay switch component can be pulled out to make the wiring adjustment easier.

1. Reconnect the power and turn on the machine.

2. Test the machine again using the foot pedal.

   • If the machine works, the issue is likely related to the delay switch or its circuit.

   • If the machine still does not work, proceed to Step 3.

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Step 3 — Check Relay KA1

1. Disconnect the machine from the power supply.

2. Pull out relay KA1.

3. Remove relay KA2 and install it into the KA1 socket.

4. Leave the original KA2 socket empty.

5. Reconnect the power and turn on the machine.

6. Test the machine using the foot pedal.

   • If the machine works normally, relay KA1 is likely faulty and should be replaced.

   • If the machine still does not work, please contact us for further troubleshooting assistance.

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Important

Please make sure the machine is completely disconnected from power before every wiring or relay adjustment.

If possible, please send us a video showing the machine operation and the troubleshooting results if the problem continues after completing all three steps.