Wireless control system cuts generator farm start time
A new wireless remote control system is reducing the time it takes to start and parallel CMS Distributed Power LLC's peak-shaving generator farms from about 1 hour to 10 minutes. These savings dramatically reduce the labor required to operate the generator sets, which supply power during peak periods to the local electrical grid and a large automotive plant.
A new wireless remote control system is reducing the time it takes to start and parallel CMS Distributed Power LLC's peak-shaving generator farms from about 1 hour to 10 minutes. These savings dramatically reduce the labor required to operate the generator sets, which supply power during peak periods to the local electrical grid and a large automotive plant. CMS Distributed Power is owned by CMS Energy (Jackson, MI).
Enabled by their new remote control system, 58 generators at two CMS sites-Zilwaukee, MI, and the Ford Rouge plant in Dearborn, MI-would otherwise take 5 minutes each to manually start and synchronize to the grid. The farm at Ford Rouge consists of 26 model 3516 diesel generators from Caterpillar Corp. (Peoria, IL) and has a total capacity of 37.7 megawatts. The farm in Zilwaukee includes 20 model 3516 and 12 model 3512 Caterpillar diesel generators with a capacity of 40 megawatts.
The wireless system starts the generators simultaneously in response to a signal from the company's headquarters. CMA adds that this wireless system was inexpensive to buy and run because it uses the overhead control channels of the firm's existing cellular network. ''This application saves us a considerable amount of time,'' says Felipe Mazzini, CMS' project development engineer.
Control system selection
Mr. Mazzini says CMS decided early on that it wanted to operate the generator sets remotely from its headquarters. CMS' engineers considered other automated controls for the generators, but a hardwired system would have been too costly because the generators are so spread out, while a cheaper modem-enabled system would have required installing telephone lines to each generator set and a variety of operating costs. ''Energy International, a Caterpillar distributor, helped us evaluate various systems, and recommended the G-Series controller from OmniMetrix (Atlanta, GA) because it provides the lowest-cost alternative that met our needs.''
Harold Jarrett, OmniMetrix's president, adds that G-Series is designed to control emergency-power generators. It turns generators on and off, and monitors fuel level, oil pressure, coolant temperature and other operations. The device generates an alert message when a failure mode is detected. Normal run and stop events are archived and reported in e-mailed summaries. The control system takes only 10 minutes to install and includes a two-day internal battery.
Using cellular networking
An essential aspect of G-Series is that it eliminates the need for dedicated, wire-line connections, and avoids the expense of hardwired or satellite-based service, by using NumereX's (Atlanta, GA) Cellemetry network. This technology reduces monitoring and control costs by using an underutilized part of the existing cellular telephone network. Cellemetry basically mimicks a roaming cellular telephone, which must register with the local cellular provider to be used outside its local service area. This same registration process is used by Cellemetry Data Service's radios to send and receive information via the network's cellular control channel to and from fixed and mobile equipment, such as vending machines, security alarms or fleet vehicles.
NumereX reports that, in applications with small data requirements, using this cellular control channel costs less, but the small size of its data packets provides a robustness that extends its service range beyond conventional, voice-based cellular networks. For example, it can penetrate multiple building walls without difficulty, and can typically communicate with cellular transceivers covering most offshore oil platforms.
Mr. Mazzini adds that CMS' Cellemetry-based OmniMetrix system successfully allows CMS to react more quickly to market shifts. ''An engineer sitting in our headquarters in Jackson can simply push a button on the computer screen to turn all of these generators on or off in a few minutes, which saves time and labor.''
-Jim Montague, news editor firstname.lastname@example.org