ETM Pacific has released the Water Surfer wireless, low-power battery or mains-operated handheld data logger. It can record water flow in metering applications to yield billing and usage data, tipping bucket contact closures to indicate rainfall, and water level (hydrostatic pressure) with 12-bit resolution. The readings are scaled and calculated to yield meaningful measurements.
The portable unit has an analogue input channel that is software-selectable to accept voltage or current, a dedicated analogue channel for monitoring battery voltage and two digital channels whose inputs are driven by voltage-free contacts. A switching output supply is also available for powering sensors before sampling and thereby extending battery life. The onboard real-time clock ensures each log is individually time stamped and allows for multiple and alternate logging rates from one second to four hours.
Information can be downloaded directly to a PC via the RS232 interface, providing for remote access using GSM/GPRS/CDMA/1X wireless technologies for real-time reporting or web delivery via the internet. It incorporates SMS alarms and logic and calendar scheduling functions. Its low standby current draw, together with a low operating voltage, enables the unit to be efficiently powered from a 9V PP3 battery.