The Customer wanted us to design and supply an Intelligent MCC that would replace the current outdated system. The Motor starters where designed to be on VFD (Sinamics G120) to optimize the energy consumption and provide flexible control. A Siemens advanced PLC S7 1500 and HMI KTP 700 was used for sequential control of the motors during startup, Alarms and Events and Operator control of the system.
The Automation was implemented using the TIA platform which makes the configuration, integration and troubleshooting easier. Energy Measurements are done using the PAC meters which are communication friendly and is linked to the existing EMS system.
Some of the major benefits to the customer
- Energy Monitoring and hence Energy Optimization
- Compact Design
- Easy to use operator interface
- Trouble shooting has become faster
- Design based on TIA
- Designed and built in Kenya
The client had a Paper machine running on one main drive – Masterdrive (800KW). The other functions where achieved by a mechanical Gear train. As the plant is old there are frequent breakdowns and very long downtimes. The customer hired a consultant/supplier to change the design from a central to a distributed drive control. IET was selected as the Electrical partner
Major Items in the Project Scope:
- 26 Siemens G120 Drives from 2.2 KW to 110 KW
- PLC control for the entire process with S7 300 PLC
- Remote ET stations – 5 no’s
- Drives on Profibus network
- HMI used is TP 900
- Siemens Switchgear – incomer 2000A 3WL ACB
Major Benefits to the Customer:
- Energy Saving as each section can be optimized & use of drives
- Much better Synchronization btw various sections
- Better line speed’s
- More flexibility as fine adjustments possible
- Reduced downtime due to mechanical failures.
- Easy to troubleshoot due to simple diagnostics
- Solution designed and built in Kenya
Upgrade from S5 to S7 PLC
The S5 PLC 115U has been phased out by Siemens. The customer wanted to upgrade to ensure continuity of support and availability of spare parts. The machine still had a number of years of mechanical life hence the customer decision. The work was to be done with minimum interruption and to reuse the existing parts as much as possible.
We selected S7 300 PLC as a direct replacement for the existing S5 PLC.The mimic display and controls where maintained as in the previous design to keep costs to the minimum. The existing cables where labeled and transferred. The S5 Program was converted to S7 Blocks, some were manually written. The system is now tested and running .Customer has now continuous availability of the machine without any concerns of spares availability and a easy to trouble shoot system