1 and 10 l/pulse are typical, depending on the size of the meter. The data transfer functions according to the NAMUR standard, whereby the power supply for the sensor and the pulse transfer are achieved by 2 wires. This functions according to the inductive proximity switch principle and detects the pulses to be generated by means of an induction coil in the sensor. The NAMUR inductive encoder is available as an alternative to the optical encoder. As an active sensor, the optical encoder requires a power supply and is usually actuated by a measuring transducer. In contrast to the reed encoder, it has the advantage that higher resolutions of the pulse value are possible. The active optical encoder is an electronic switch that generates the impulses by means of a photoelectric barrier integrated in the counter as standard. The reed contact does not require its own power supply and hence is the ideal partner for all auxiliary battery-powered electronic equipment. Typical pulse values are 100, 1,000 and 10,000 l/pulse – depending on the size and mounting position of the meter. It is actuated by means of a magnet integrated in the counter as standard, by a frequency in proportion to the flow. Active sensors are typically actuated by a measuring transducer, which requires a power supply.įunctioning as a passive pulser, the reed contact is designed as a potential-free N/O contact. Like the 620C, the Sensus 640 is fully recyclable using composite materials making it truly environmentally friendly. The Sensus HRI sensors allow for automatic meter reading through a fixed network using M-Bus or radio, telephone or GSM modem. The Sensus 640C has been designed in conjunction with the Water Utilities to provide exceptional performance coupled with the very latest wireless communications technology. We designate all contact transmitters that do not require their own power supply as passive sensors. Sensus HRI Sensor The Sensus High Resolution Interface (HRI) is a smart universal output/communications sensor which can be retrospectively fitted to a wide range of Sensus Water Meters. Up to 2 reed contacts and an active pulser can be connected at the same time.