... flowmeters are made up of sensor and transducer, together with LCD screen, current and pulse output, alarm signal and ... or 4~20mA;- Frequency Output: 0~5000Hz with photoelectric isolation;- Pulse Output: 0.001~1.000m3/cp, 0. ... Upper Alarm-ALMH, Lower Alarm-ALML with photoelectric isolation;- Communications: RS-485 with Galvanic isolation, MODBUS. high quality electromagnetic digital water flowmeters