The alarm unit M2118 is used to check or control any type of signal current or voltage signal. It converts the input signal to an internal standard signal of for example 0 to 100.0%. In this range two alarm contacts can be set independently. A 4-digit LED display shows the actual value and setpoints or alarm values in the range of -1999 to 9999 units.
All settings as alarm values, hysteresis, range and operating mode of the floating contacts can be set with a link cable, connected to a personal computer or a laptop.
Both alarm contacts can also be programmed with tiny push button switches.
A typical application would be to measure and monitor pressure in a process vessel. The pressure transmitter converts the pressure of 1 to 10 bar to a current signal of 4 to. 20mA. The M2118 monitors under- and overpressure in the vessel. It converts the 4... 20mA signal current to 0...100.0%. The alarm is set between 0% (=1 bar) and 100.0% (=10 bar). With these floating alarm contacts, overpressure valves, compressors, etc. are driven directly.
Optionally, a galvanic isolated output signal of 0...20mA or 4...20mA is available.
Power supply: Universal supply 20 to 253VAC/DC