DID YOU KNOW?

Scaled vs. unscaled pulse settings can change how accurate your flow data really is.

Scaled Pulse vs. Unscaled Pulse

Understanding digital outputs in FLOMEC flow meters

Unscaled pulses preserve the flow meter’s full K-factor resolution, delivering the most precise and reliable flow measurements—especially for rate monitoring.

"Did You Know?"
Scaled Pulse vs. Unscaled Pulse – What’s the Difference and Which is Best?

At FLOMEC, many of our flow meters and electronic displays include a digital output, often called a frequency output or pulse output. These pulses represent the flow measured by your meter. Each flow meter comes with a K-factor, which is the exact number of pulses per unit (gallon or liter) produced by the flow meter. Your display can transmit these pulses to external equipment such as PLCs, data loggers, or batch controllers. FLOMEC displays offer two options: unscaled pulse and scaled pulse.

What’s the Difference?

Unscaled Pulse

Sends the exact number of pulses per unit based on the meter’s K-factor.
Often called a repeater pulse.
Best resolution = best accuracy.

Scaled Pulse

You program the flow meter to output a specific number of pulses per unit (e.g., 10 or 100 pulses per gallon).
It can only scale down to fewer pulses than the original K-factor.

Why Unscaled Pulse Is Usually Best

Higher resolution means better accuracy. Using unscaled pulses preserves the complete detail of your measurement.

Example

Your meter’s K-factor = 500 pulses per gallon (ppg)
Flow measured = 24.257 gallons

Pulse Setting	Display Reading
Scaled to 1 ppg	24.000 gallons
Scaled to 10 ppg	24.200 gallons
Scaled to 100 ppg	24.250 gallons
Unscaled (500 ppg)	24.257 gallons

Monitoring Flow Rate?

If your system calculates the rate of flow, it looks at pulses per second. Lower resolution means fewer pulses per second, which can significantly impact accuracy—especially if your equipment updates every second.

Bottom Line:

Unscaled pulses deliver the highest resolution and the most accurate results.