CAT3 provides a Pulse Output option that is scaled per flow unit of measure. One output pulse represents one count of the least significant digit of the total. When observing metered flow on an external counter or oscilloscope, the pulse output will display bursts of metered units due to the number of pulses in each 1 second increment of time determined by the Pulse Frequency setting. For steady flow, an oscilloscope will show the pulses per second for each second, a counter may seem erratic and increase 2 units for the first second then 3 units for the second (displaying as follows; 0, 2, 5, 7, 10…). The maximum number of pulses per second is 100.

The following configuration parameters affect the operation of pulse output.

Total Decimal Places
Sets location of the total decimal places after the decimal. Select 0, 1, 2, or 3 (xxx, xxx.x, xxx.xx, xxx.xxx).
Total decimal point determines the resolution of flow total.

E.g. If total decimal point is set to 2 (xxx.xx), one output pulse represents 0.01 of total in selected units of measure.
If flow rate is 30GPM, which equals to 0.50 gal per second, there will be 50 output pulses per second.

Pulse Scale:
Allows the user to reduce the output frequency when the turbine pulse frequency is too high. If Pulse Scale OFF is selected, then the pulse output is disabled.
Select 1, 10, 100. Number of output pulses can be divided by 1, 10, 100. The divider is used when output frequency exceeds the CAT3 max allowable number of 100Hz.
Note, number of output pulses can be also reduced by changing Total Decimal Places.

Pulse Frequency:
Sets Frequency/Pulse Width for output pulse. Select 1, 2, 4, 8, 100 cps. (cps – cycles per second).
Note, output pulse duty cycle is about 50%. Changing pulse frequency sets pulse width per below table.