Data Logger for Water Meter Function Continuously counts pulses from pulse output of the water meter (or other meters with pulse output) and periodically records non-zero values to internal nonvolatile memory for further data transfer to PC. Features • Input Pulse frequency up to 20Hz with digital filtering for debouncing cancelation • Isolated input for Reed Switch or Voltage Pulse • Selectable Recording Period (beginning from 1s with 1s step) • Nonvolatile memory for data storage: a) FRAM (2Mbit for 37400 records) b) microSD card optionally (up to 2Gbit) • Interface with PC for remote data reading: a) Isolated RS-485 interface with selectable Baud Rate up to 460800 baud/s b) Optional GSM/GPRS communication (TCP/IP) • Data archiving and visualization on the PC • +5…12VDC power supply • Package for DIN rail mounting • Operating temperature range -25…+75℃ Data Logger connection to Meter and PC RS-485 • Bus length up to 1 km • Selectable baud rate up to 460800 baud/s • Virtual COM port GSM/GPRS • No wires, no distance limitation • Onboard SIM card with connection to mobile Internet • TCP/IP communication protocol Block diagram of the Data Logger Input Circuit Digital anti debouncing filtering algorithm is implemented in MCU program. Minimal pulse width is limited at 25ms, that allows pulse rate up to 20Hz. Pulse Input accepts Reed Switch and Voltage Pulses (up to 36V). See figures on the left for more info. Input Circuit protection against reverse polarity of the signal. +5V +5V GND GND MCU Pulse In IN+ Pulse INGND Operation principles Recording Period is designated as T on the time diagram above. When this interval expires, non-zero value of the Pulse Counter with time stamp (seconds, minutes, hours, days, weekdays, months, years) are written to the nonvolatile memory. Then Pulse Counter is cleared to start counting pulses for the next recording period. Recording period selectable from 1s with 1s step. 20-bit Pulse Counter is used for counting pulses. PC software. Setup and configuration. Main window Configuration of the virtual COM port Setting and reading parameters Data visualization. Table and chart formats. Data Logger records In March Daily water consumption in March Data archiving on the PC Data export to Excel Detailed data representation for short time interval The same data, but current value is added to the sum of previous values. The last value is equal to total water consumption for selected time interval.