Background
UK manufacturer of remote water monitoring and control systems for irrigation, drainage systems, and data loggers wanted to use RF telemetry in feedback of the status and situation of their equipment. Many items are installed in boreholes and often subject to immersion under flood conditions and need to operate reliably under these conditions.
Brief
SMA interface waterproof adaptors needed for connecting to GPS antenna, second SMA interface required for RF transmission antenna to provide location and system status.
Internal connections via MCX cable link. This allowed ease of equipment installation and assembly and the possibility to upgrade or replace internal components when necessary.
External connector to be sealed to IP68, unused connectors installed to allow for future upgrade (i.e. activation of GPS) needed blanking caps fitted.
Challenges
Equipment installed in boreholes which are prone to flooding, silting up, wide operating temperature range (equipment installed outside). Ease of assembly and possible upgrade require an adaptor, commercial product requires competitive pricing. Aggressive environmental conditions (temperature, contaminants etc.) need to be considered.
Solutions
This project needed customer liaison to ensure all the performance requirements could be met using a standard SMA/MCX waterproof adaptor. The cable assembly needed to be customised to the correct length, and a disposable dustcap that offered environmental protection of any unused connection whilst installed in situ.
Summary
This product uses a standard SMA/MCX waterproof adaptor and the design, so the customers prototype designs were evaluated using samples held in stock (the first samples were shipped direct to the customer at a trade show to fit into his demonstration unit). Prototypes and qualification samples were provided over the next two years and the product went into production in 2014.