The panel meter 2251 is designed for two pulse sensors such as NPN-, PNP-, Namur -sensors, closing contact or pickup. The meter calculates the difference between the input frequencies, subtraction A-B, or alternatively, the meter divides the input frequencies, division A/B.
The input frequency range 0,0001Hz..5 kHz is exceptionally wide starting with very low frequencies. The display is scaleable on the whole frequency range, e.g. 0-1,23 Hz can correspond to the range 0-5000 on the display. Output is freely scaleable on the basis of the display, e.g. 4-20 mA. Two different measuring methods are applied: in low frequencies the time interval between two incoming pulses is measured and in higher frequencies the frequency.
Load manuals (pdf)
Load datasheets (pdf)
Load technical drawings
Namur, Pickup, PNP, pulse sensors, closing contact
0.01% full scale
24 VDC, max. 150 mA
number of digits
alarm levels 1 and 2
24 VDC: 70...110 mA depending on the digit count
24 VDC: 12...32 VDC / 24 VAC, 230 VAC: 85-260 V AC/DC