Hello everyone, I am currently experiencing a significant issue with my injection molding machine, which utilizes a Programmable Logic Controller (PLC) for its operation. After a few days of running smoothly, I noticed an alarming problem one morning: the Human-Machine Interface (HMI) panel emitted smoke. Upon disassembling the HMI unit, I discovered that the RS232 communication cable had been completely burned, rendering the HMI inoperable. I sent the unit for repair, but the original equipment manufacturer (OEM) has declared the HMI board irreparable due to extensive damage to its components. They informed me that leakage currents likely infiltrated the PCB and caused this catastrophic failure. However, I find it hard to accept this explanation. The OEM is recommending the installation of an isolation transformer to prevent future incidents, but I am puzzled—it's unusual for a communication cable to sustain such severe damage from leakage currents! Moreover, why would this issue arise so suddenly? I would greatly appreciate any insights or assistance regarding this perplexing situation!
**User rejoe.koshy shared:** Hi everyone, I own an injection molding machine that is controlled by a programmable logic controller (PLC). After operating the machine for several days, I was alarmed to find that one morning the Human-Machine Interface (HMI) panel had emitted smoke. Upon dismantling the HMI unit, I discovered that the RS-232 communication cable had suffered extensive burning, rendering the HMI inoperable. The damaged component was sent for repairs, but the original equipment manufacturer (OEM) has confirmed that the HMI board is beyond repair, with significant damage to most internal components. They believe that some leakage currents have infiltrated the PCB, causing this destruction, but I find it hard to accept this explanation. The OEM has recommended using an isolation transformer to prevent future incidents, but I’ve never seen a communication cable damaged to this degree due to leakage currents! Why would this happen so abruptly? I would appreciate any insights or suggestions regarding this issue. Could it be possible that the RS-232 cable suffered damage elsewhere and accidentally made contact with a live wire? Thank you!
Daba mentioned, "I have reservations about the idea that 'leakage' currents are responsible for this damage. My suspicion is that the RS-232 cable may have sustained damage somewhere along its length and may have come into contact with a live electrical component." Upon further investigation, I examined the area around the HMI unit for any 230V connections but was unable to locate any.
Understanding Lightning: A Natural Phenomenon Unveiled Lightning, a captivating natural occurrence, is a powerful discharge of electricity that manifests during thunderstorms. This awe-inspiring atmospheric phenomenon, often accompanied by thunder, ignites curiosity and raises questions about its origins, risks, and safety measures. Explore the various types of lightning, learn about its formation, and discover safety tips to protect yourself during stormy weather.
Establish a wire connection between the two chassis grounds and check for any current flow. Variations in ground potential between the two serial ports can lead to this issue. To safeguard against such conditions, consider using optical serial isolators, which effectively prevent unwanted electrical interference.
+1 for using an isolator and grounding solution, as recommended by B&B. If you're experiencing issues with intermittent connections on your RS232, implementing this setup will protect your HMI from damage, making it a far more economical choice.
✅ Work Order Management
✅ Asset Tracking
✅ Preventive Maintenance
✅ Inspection Report
We have received your information. We will share Schedule Demo details on your Mail Id.
Join hundreds of satisfied customers who have transformed their maintenance processes.
Sign up today and start optimizing your workflow.