Troubleshooting

This section focuses on the most common operational issues and how to resolve or diagnose them using the screen and web interface.

No GPS Lock / Sync Searching

Symptoms:

  • Satellite count is low or zero.

  • Sync indicator shows searching.

Actions:

  • Verify the GPS antenna is connected to the BNC port.

  • Move to an open area with clear sky view.

  • Wait a few minutes for initial acquisition.

Transmit Button Disabled

Symptoms:

  • Transmit is disabled on the web UI.

  • The screen does not show RDY.

Actions:

  • Press RESET to start the reset/arm sequence.

  • Wait for RDY (arm window). The window is short (about 2 seconds).

  • If RDY never appears, note the displayed code and use the Error Codes and Corrective Actions.

Error Codes and Corrective Actions

An error code identifies the protection function or subsystem that prevented operation. The controller disables the transmitter output and returns to a safe wait state whenever an error is detected.

Codes beginning with a subsystem prefix identify the reporting module:

  • SM – Safety module

  • MM – Monitoring module

  • GM – Gate-driver module

  • FM – Cooling/fan module

Warning

An error code means that a protection condition has stopped operation. Do not bypass an interlock or repeatedly reset the unit without correcting the cause. Connected power equipment may remain hazardous even though the ZT-100 has disabled its transmitter output.

Error-code reference

Display code

Meaning

Operator response

ERR

The shared system error line is active, but a more specific source has not been identified.

Keep the unit stopped. Check the supply, transmitter, load, and cable connections. After correcting any visible problem, press RESET once to run the protection check again. If ERR returns without a more specific code, contact Zonge International technical support.

ORE

The measured load resistance is outside the configured Minimum Resistance and Maximum Resistance limits, or the resistance measurement did not complete within the allowed time.

Check the transmitter cable and load circuit, then confirm that both resistance limits are appropriate for the installation. Press RESET and repeat the transmit sequence only after correcting the cause.

SM EMER

The emergency-stop input is active.

Make the work area safe, determine why the emergency stop was activated, and release it only when safe to do so. Verify the emergency-stop circuit, then press RESET.

SM GIUV

The safety module’s global input under-voltage protection is active.

Verify the input power source and power connections. Restore the input voltage to the permitted range, then press RESET.

SM GIOV

The safety module’s global input over-voltage protection is active.

Verify the input power source and power connections. Restore the input voltage to the permitted range, then press RESET.

SM UDIUV

The input voltage is below the user-defined Input Under Voltage limit.

Compare the configured limit with the actual input voltage. Correct the supply condition or, if authorized, set an appropriate limit; then press RESET.

SM UDIOV

The input voltage is above the user-defined Input Over Voltage limit.

Compare the configured limit with the actual input voltage. Correct the supply condition or, if authorized, set an appropriate limit; then press RESET.

SM LERR

The safety module has asserted its local error flag without a more specific safety input code.

Confirm that the emergency-stop and input-voltage conditions are normal, then press RESET once. If the code returns, contact Zonge International technical support.

SM ERR

The safety module reported an error that is not represented by a more specific display code.

Record the code and operating conditions. Press RESET only after all safety inputs are normal. If the code returns, contact Zonge International technical support.

MM OVP

Over-voltage was detected on the positive output half-cycle.

Keep the unit stopped and inspect the transmitter, load, cable, and operating setup. Press RESET only after correcting the cause. If the code returns, have the system serviced.

MM OVN

Over-voltage was detected on the negative output half-cycle.

Keep the unit stopped and inspect the transmitter, load, cable, and operating setup. Press RESET only after correcting the cause. If the code returns, have the system serviced.

MM OCP

Over-current was detected on the positive output half-cycle.

Keep the unit stopped and inspect the transmitter, load, cable, and operating setup. Press RESET only after correcting the cause. If the code returns, have the system serviced.

MM OCN

Over-current was detected on the negative output half-cycle.

Keep the unit stopped and inspect the transmitter, load, cable, and operating setup. Press RESET only after correcting the cause. If the code returns, have the system serviced.

MM LERR

The monitoring module has asserted its local error flag without a more specific voltage or current code.

Press RESET once after confirming that the transmitter and load connections are correct. If the code returns, contact Zonge International technical support.

MM ERR

The monitoring module reported an error that is not represented by a more specific display code.

Record the code and operating conditions. Press RESET only after checking the transmitter and load. If the code returns, contact Zonge International technical support.

GM OTMP

The gate-driver module temperature exceeded its protection threshold.

Allow the unit to cool. Check ambient temperature, ventilation, and fan operation, then press RESET. If the code returns, do not transmit; have the cooling and gate-driver systems serviced.

GM LERR

The gate-driver module has asserted its local error flag without a more specific temperature code.

Press RESET once after confirming that the unit has adequate cooling and all external connections are secure. If the code returns, contact Zonge International technical support.

FM LERR

The cooling/fan module has asserted its local error flag.

Check that vents are clear and that the fans operate normally. If a fan is not operating, do not transmit. Press RESET once after correcting the cause; have the cooling system serviced if the code returns.

The display reports one protection label at a time. If more than one condition is active, correcting the displayed condition and pressing RESET may reveal another code. The unit is ready to transmit only when the reset check completes and RDY appears.

If a code persists after the stated checks, record the exact code, operating mode, frequency, connected equipment, and the conditions immediately before the stop. Provide this information to Zonge International technical support.

Wi-Fi Not Visible

Symptoms:

  • No ZT-100 SSID appears.

Actions:

  • On the front panel, open More Info and set Wi-Fi status to ON.

  • Wait for the Wi-Fi icon to appear on the top bar.

Can’t Open the Web UI

Symptoms:

  • Browser cannot reach the device page.

Actions:

  • If in hotspot mode, connect to the device SSID and open http://10.10.10.10/.

  • If in local network mode, use the IP address shown on the screen.

  • Confirm Wi-Fi status is ON.

Custom File Upload Fails

Symptoms:

  • Upload rejected or file not listed.

Actions:

  • Ensure the file extension is .usm.

  • The web UI rejects files larger than 256 KB.

  • Stay in Custom mode while uploading.

OTA Update Fails

Symptoms:

  • Upload rejected or target mismatch.

Actions:

  • Confirm the firmware file matches the selected target in the web UI.

  • If the upload is rejected, re-check target selection and file version.

  • Keep the browser open until the update process completes.