The Laureate™ dual-channel frequency meters can measure AC line frequency to 50.0000 or 60.0000 Hz with 0.0001 Hz resolution in a few line cycles. They can measure 1000 Hz signals with 0.01 Hz resolution at up to 25 readings per second. Such fast response is ideal for alarm and control applications.
The Laureate frequency meter can display frequency from 0.005 Hz to 1 MHz, rate in engineering units, and period (inverse of frequency). The normal displayed value can range up to 999,999 counts. Above that level, the display will flash and go into four-digit XXXXEX scientific notation. Square root extraction is standard. Each channel (A or B) may be independently scaled for frequency, rate or period. The displayed channel is selected via a front panel pushbutton.
The Laureate frequency meter determines frequency by timing an integral number of periods over a specified gate time, and then taking the inverse of period. Rate is obtained by multiplying the input by a programmable scale factor. The inverse period approach allows greater accuracy and faster update times than conventional meters which count signal pulses over a specified time interval.
An Extended frequency meter version provides capabilities beyond those of the standard meter:
- Rate and total simultaneously. One frequency meter channel can display total while the other displays rate. The selection for either channel is via a front panel pushbutton. This mode is ideal for flow applications when the same signal is applied to both channels.
- Linearization of nonlinear inputs. Exceptionally accurate custom curve linearization capability allows linearization of the low end of turbine flow meters. The Extended frequency meter version allows linearized rates to be totalized.
- Arithmetic functions. The Extended frequency meter makes arithmetic functions available, namely A+B, A-B, AxB, A/B and A/B-1 (draw). For example, A+B allows two input flows to be summed for total flow, while A-B allows outflow to be subtracted from inflow for net flow. If transducers with a frequency output are used, AxB allows horsepower to be displayed based measured torque and RPM, or based on force and velocity. A/B can be used for the proper mixing of ingredients, while A/B-1 (draw) is used to compare rates for stretching or tensioning.
For specifications and additional operating modes of Laurel frequency meters, please see:
Exceptional flexibility is achieved for Laureate frequency meters by programmable features and up to 5 plug-in boards in addition to the main board. Please see our Laureate product line overview.