Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/351731
AGGREGATES MANAGER August 2014 24 D owntime on dredges due to electronic equipment failure varies based on the level of automation, age, hardware brand, size, use, and environment on each dredge. Additionally, downtime varies based on the response and level of competence to individual trouble issues. One thing is for certain: Downtime can last days or weeks as opposed to minutes or hours without the proper in-house skill set competence or spares parts. Understanding control wiring diagrams Wiring diagrams typically begin with the power and power-supply sections. Next, comes the actual PLC (Program- mable Logic Controller) fi eld inputs and outputs (see Figure 1), also known as I/O, or the relay ladder logic wiring for older relay style control systems. is is where you will fi nd wire numbers to specifi c fi eld devices (such as transmi er sensors, switches, thermocouples, push bu ons, motor starters, VFD interconnections, etc.) that will guide you to the proper fi eld terminal when doing your fi eld voltage or milliamp (ma) current testing. Tips and tricks for troubleshooting dredge sensors and other electronic equipment. by Jay Wise Sensor Solutions Figure 1. Typical PLC I/O section of a dredge control wiring diagram.