| The AP7500 and AP7501 are
useful in totalizing applications, where the total number of pulses counted in
a given time period represents the time integral of the DC input. If, for
example, the input represents a flow in gallons per hour, then the time
integral of this flow signal (total count) will represent total gallons (see
Figure 1). The AP7500’s 6V square wave output can be used to drive
electronic counters (DTL, TTL, CMOS). The AP7501 can be used to drive
electromechanical counters when connected to an external AC or DC power source.
In the AP7501, the DPDT relay contacts are pulsed (closed) for only a short
duration (100 milliseconds) for compatibility with standard electromechanical
counters. The AP7500 can also be used in telemetry systems, where the dc signal
is converted to a frequency, transmitted over long lines, and then decoded at
the receiving end by means of a frequency to DC converter, such as the
AP7380. |
