Changeover contact, GEMU 1250
Limit switches, GEMU 1251-1257 for flowmeters operating on the variable area principle. Reading of the level of the float at the switching points.
Instrument sensors, GEMU 1270-1273 for flowmeters operating on the variable area principle. Continuous reading of the level of the float.
A change-over contact is built into the limit switch.
Bistable reed contacts are built into the limit switches which are actuated by the magnet incorporated in the float.
The instrument sensors contain reed contacts which are triggered by the magnetic flowmeter float. GEMU 1270/1271 have a voltage output signal via voltage divider.
GEMU 1272/1273 are equipped with an integrated 2-wire measuring transducer and realize a current output signal.
The limit switches and instrument sensors are fixed to the dovetail sections moulded onto the flowmeter type series GEMU 800 and GEMU 850 (see data sheets 800/850). The float in the flowmeter is equipped with a permanent magnet for this application.
When the magnetic float has passed the contacts fixed to the tube at least once, the following conditions occur:
above below contact contact Max. contact (GEMU 1251/1256) closed open Min. contact (GEMU 1252/1257) open closed
The contacts then remain in this position, even if the float moves a long way from the min. or max. contact and will only change when the float passes the respective contact again.
The reading from the GEMU 1270/1271 instrument sensor is emitted as voltage output signal via a voltage divider (0-10 kΩ). GEMU 1272/1273 produce a current output signal which can be directly processed without any further conversion. The function of the limit switches or instrument sensors is neither affected by the working pressure, nor by the conductivity, concentration or density of the medium. The application of the flowmeters with continuous reading or limit switches together with a measuring transducer is suitable for use with conducting, non-conducting and also with turbid media.