Jim ‘Slim’ Mimlitz, SCADAmetrics
The SCADAmetrics model SB.202 Smart Bell.202 Modem is designed to provide wireless SCADA and Telemetry communications in the utility, petroleum, and industrial sectors — and particularly in situations where communications across long-distances and/or through heavy foliage is required.
The model SB.202 fills the void left by the discontinuance of the Calamp DM.3282 modem, the Control Microsystems 5902 modem, and the Mille Applied Research MARC 202 modem.
With its opto-isolated RS.232 serial interface, internal circular transmission buffer, and automated radio push-to-talk control capability, the SB.202 exists as the most advanced and easy-to-use Bell.202 modem ever manufactured.
Within wireless SCADA and Telemetry systems, the establishment of reliable communications is the endeavor which requires a high level of skill and experience from the integration professional. Subsequent to successful installation, maintenance and repair of these systems requires perhaps even greater skill.
The purpose of this article is to provide an overview of the typical components of a Bell.202 radio modem system, and to also provide guidance for field troubleshooting a faulted communication system.
Consider the Circumstances Preceding the Failure…
When troubleshooting a Bell.202 radio-modem system, it is important to first consider the circumstances of the initial failure:
- Did the failure occur subsequent to a lightning storm? Consider an electrical surge to the electronic equipment or possibly a lightning strike on the antenna.
- Did the failure occur subsequent to a high-wind storm? Consider a physically-damaged antenna, or a broken coaxial cable connector.
- Did the failure occur during an ice storm? Consider ice buildup on the antenna as the problem, which should generally clear up after the ice melts.
- Did the failure occur subsequent to a heavy rain storm? Consider water ingress into an improperly-sealed antenna and/or antenna coaxial cable connector.
- Is an antenna or coaxial cable or coaxial connector failure suspected? Consider using a Bird model 43 directional RF wattmeter to diagnose and pinpoint the location of the problem.
Benefits of Swapping with Spares…
If Bird directional RF wattmeter troubleshooting points to a problem with the antenna or coaxial cable, then it’s probably time to suit up with safety climbing gear, RF cabling tools, spare connectors, a spare antenna, and weather sealing tape (3M Super 33+ is recommended.).
If the antenna and coaxial system appears to be fully functional, and a control panel component is suspected as faulty, then the suspected component should be replaced with a new (known-good) identical component; and the system should be observed for whether the fault has cleared. If not, the original component should be reverted, and troubleshooting should move on to the next suspected faulty component.
Questions?…
Are you interested in learning more about how the SCADAmetrics model SB.202 Smart Bell.202 Modem can serve as the backbone for ultra-reliable wireless data communication across long distances and through heavy foliage? Give us a call!… We’ll be glad to discuss the details!