HMI Errors and Communication Faults
HMI error messages and communication faults sit between the display and the controller: cabling, device state, or a parameter/project mismatch after replacement. The exact error text is the diagnosis's starting point.
Problem
The HMI shows an error or communication message, loses values or screens, or fails to start with the controller. Machine behavior may continue or stop depending on where the fault sits.
Possible Causes
- Communication cable or connector fault between HMI and controller.
- Controller or HMI stuck in an abnormal state after a power event.
- Electrical noise or grounding conditions affecting communication.
- Power interruption during operation.
- Parameter or project mismatch after a component replacement.
What to Check
- STEP 1Record the exact error text.Photograph the screen including any code — never clear it before recording.
- STEP 2Check cables and connectors.Verify the communication cable is seated at both ends and undamaged, including its route away from power cables.
- STEP 3Restart per the machine manual.Follow the documented restart sequence for the HMI and controller — order matters.
- STEP 4Review recent electrical work.Check whether nearby electrical changes coincide with the fault's first appearance.
- STEP 5Check for a replacement event.If the HMI or controller was replaced, verify parameter and project sets were transferred completely.
Corrective Actions
- Reseat and secure communication cabling; keep it routed per the original layout.
- Bring the documented restart procedure to the panel so it is followed exactly.
- Never load or edit controller projects without authorization from Path Pack.
- Escalate with the photographed error text and the sequence that leads to it.
Contact Path Pack with the recorded error text whenever an HMI or communication fault recurs, follows a power event, or appears after component replacement. Do not open control cabinets or modify controller projects — these are serviced per Path Pack documentation.
- Machine model
- Serial number
- Film specification
- Production speed
- Photos / video
- Alarm information
Advanced Diagnostics: PLC and Controller Side
When errors persist through cabling and restart checks, the fault sits deeper — between the HMI project, the controller program and the communication link. This territory has one governing rule: verify and back up before changing anything.
- STEP 1Back up before any intervention.Controller and HMI projects are archived before they are touched — an unbacked change is unrecoverable by definition.
- STEP 2Compare the error against the documented fault list.The machine documentation maps controller fault codes to causes — never diagnose from the message text alone.
- STEP 3Verify the communication path.Confirm the HMI-controller link: cable route away from power runs, connectors seated, termination unchanged.
- STEP 4Reproduce, then record.Note the exact sequence that leads to the fault — sequence information is what remote support needs most.
Controller projects, parameter sets and safety programs are serviced per Path Pack documentation. Do not load, edit or "restore" projects without explicit instruction from Path Pack technical support — provide the recorded fault sequence and request remote assistance instead.