Introduction

This simple wall, or in some cases, flowmeter mounted instrument gives an analogue output proportional to flow. Three basic models are available offering 0/4 to 20 milliamp, 0 to 5 volt and 0 to 10 volt outputs. In all cases the offset and full scale adjustments are independent of each other. The standard converter has an input frequency range of 0.5 to 850 Hz. This is selectable via a pair of DIL switches. A special lower range version is available for use with lower frequency inputs such as positive displacement flowmeters, this device operates down to 0.25 Hz. At these very low frequencies the output can be “damped”. Two status LEDs indicate whether pulses are being received and if the output is operating within its selected flow range. The enclosure is a high impact polymer that seals the unit to IP65 (NEMA 4X). Access to the terminals is via a pair of glands on the bottom of the enclosure.

Calibration

As with nearly all of our products calibration is performed for you at our factory on  equipment that has traceable calibrations to national standards. If for any reason the analogue converter requires recalibration in situ the following procedure may be followed.

1. Select from the chart below the anticipated maximum frequency operating range for the converter.

2. With no pulse input (or your minimum) set the zero flow output. This may be 0 volts, 0mA or 4mA depending on the requirements.

3. Set the flow to your maximum or inject a frequency equivalent to this and adjust the span potentiometer to give your required full scale.

4. If the output LED shows an over or under range status select the next frequency range up or down and start again.