The SR2700 is a flexible frequency input two-wire transmitter for Head or DIN rail mounting. It provides a 4 to 20 mA output proportional to the frequency of the input signal.
The input circuit is capacitor coupled so an AC signal imposed on a DC voltage can be measured. Sine or square wave AC signals may also be measured.
A pull-up resistor is provided so the input can be derived from a switch, contact closure, or an open collector NPN transistor such as an optical isolator.
A plug-in range card determines the operating frequency of the unit. 10 cards are available which cover the range from 12.5Hz to 12800Hz full scale. Each card covers a 2 to 1 range (i.e. 12800 to 6400 Hz). Full scale can be any frequency in the range of the card.
Filtering of the Frequency to DC converter signal allows a 20 to 1 dynamic range below the Range Card’s lowest Full Scale frequency. (RC-20)
Range cards are also available with a 10 to 1 dynamic range below the Range Card’s lowest Full Scale frequency. These Range cards provide a faster response time. (RC-10)
Optional special filters can be provided with a custom dynamic range below a selected Full Scale frequency. The filtering circuits are in the Range Card.
The Zero and Span controls are available on the top of the case.
Test points on the top of the case allow measuring the output current without breaking the loop.
The SR2700 is enclosed in an extruded aluminum case with an aluminum back plate. An optional clip is available for mounting the SR2700 on a DIN rail.
TYPICAL APPLICATIONS
Turbine flow meters
Paddle wheel flow meters
Rotating machinery speed
Conveyor speed.
Wind mill rotational speed
Frequency of AC from a generator
Wilkerson Instrument Co. 800-234-1343
