SEPTEMBER 30, 2013

REPLACEMENT LOAD BANK CONTROL SYSTEM - SIEMENS ENERGY TEST FACILITY, HOUSTON, TEXAS

Northwest Electrical Services LLC has been performing Generator and Protection Systems Factory testing and site start-up on a regular basis for years. Siemens’ test Facility in Houston Texas, utilized an Allen-Bradley PLC for lad bank control along with a Rockwell RSView system for operator interface.

The system was no longer maintainable, and the logic and interface would often subject the generator / turbine to unwarranted load changes. This would cause complications during load and witness testing for their clients. Siemens contracted Northwest Electrical Services to redesign the load bank PLC program and operator interface to allow:

• New operator interface based on Wonderware Intouch
• Allow individual selection of load bank resistors on or off in a controlled manner such that load step changes are within the test or machine parameters
• Trending tool to include in test results for electrical quantities
• Modified PLC program to accomplish the above as necessary
• Commission and turnover

Northwest Electrical supplied and installed the system at Siemens Houston Facility, including alarm screens, integrated trend tools, dual action / confirmation operator actions, load step interlocks, and load bank interlocks. The system has been in use since 2013, greatly simplifying the test procedures for Siemens’ clients.