Drive operating status and speed are communicated to the programmable automation controller via the network. When the RAH is in auto mode, the unit is stopped and started from the controller via the network.
The controller closes the temperature PID loop based on the actual temperature in the clean room and the desired setpoint. The controller automatically adjusts the motor speed as needed to keep the clean room pressurized.
Figure 3: The drive’s I/O provides a distributed I/O drop that’s networked back to the controller. The drive is mounted on the RAH, providing easy termination of the I/O devices at the unit.
An EtherNet/IP connection routes critical operation information to a central control room. From there, the HMI software provides operators information about each unit’s status including fan speed, supply temperature, setpoints and control valve output percentage.
“Access to information is the foundation of intelligent motor control. One of the benefits of using the intelligent drives is that they provide about five times more information than a non-networked drive,” adds Mays. “That gave our customers the competitive advantage to review trending information and schedule preventative maintenance, a critical step considering these plants often run all day, every day.”
Based on previous experience, IDC understands how critical network certification is to eliminating and preventing communications issues. Once the ControlNet network was in place, IDC called on Rockwell’s network engineering specialists to help verify and validate the network.
These specialists tested the network to make sure that the signal loss across the network was acceptable, network lengths were not exceeded, and that all connections were made properly. Network verification reduces the risk of discovering last-minute problems, when they’re often more difficult to identify or can have a worse impact on the overall project schedule.
More than $500,000 Saved
The intelligent motor control solution helped save the semiconductor fab owner more than $500,000 in installation costs, according to IDC’s estimates. Reduced wiring, centralized configuration and maintenance generated real savings during the start-up and commissioning of the project. The fab owner will continue to reap savings through better control, enhanced diagnostics, and easier troubleshooting. For example, if one of the drives needs to be replaced or a unit moved to a new location, configuring it will take just a few minutes, compared to more than an hour in the past.
“Programming the drives and ns conrollers and a couple of hundred motors used to take a couple of months, but now we can create software profiles and templates, and just and paste them into each device with fewer mistakes and more consistency,” adds Goh. “This can save lots of time and money because downtime costs so much. User can now save at the design, engineering and commissioning, maintenance, and other stages of the lifecycle—especially as they gain more of the benefits of predictive maintenance.”