Applicable Systems
Haitian Injection Molding Machine
Symptoms
The Haitian injection molding machine displays alarm HT008, indicating mold open limit switch fault. The mold open position limit switch is not triggering, preventing the machine from completing the mold open cycle or starting the ejection phase.
Possible Causes
- Limit switch is physically damaged or the actuator cam has shifted position
- Limit switch wiring is broken or the connector is loose, preventing the signal from reaching the controller
- Limit switch contacts are oxidized or worn, causing intermittent or no signal
Troubleshooting Steps
- Step 1: Inspect the limit switch and actuator cam for physical damage or position shift
Switch is intact and the cam actuates it at the correct mold open position - Step 2: Check the limit switch wiring and connector for continuity and secure connection
Wiring is continuous and the connector is tight with no corrosion - Step 3: Test the limit switch contact resistance by actuating it manually and measuring with a multimeter
Switch closes cleanly when actuated and the contact resistance is near zero ohms
How to Reset
To reset: 1) Replace the damaged limit switch or reposition the cam. 2) Repair wiring and connectors. 3) Replace oxidized contacts. 4) Press RESET. 5) Verify the mold open cycle completes and ejection starts.
Source: Haitian Injection Molding Machine Manual, Haitian International Holdings
Category: Injection Molding