The reading seems erratic

Possible Cause:                                                                                    Remedy:
Incorrect grounding of the flowmeter can affect reading Flowmeter should only be grounded to liquid (see also here)
Air is interrupting the measurement ensure the sensor is fully submerged
Air is trapped on top of pipe   install the sensor at an angle
Air is being pulled in through vortex move sensor to different location
Sensor or cable may be damaged  return for repair
measurement accurately reflects reality none
pipe is empty  none (turn off flowmeter)
sensor cable has been detached  re-attach cable (turn power off first !)

The meter reads low or high compared to another source of information (other instrument, pump curve, etc.)
The comparison meter is not set to the same range When comparing two instruments make sure they are both using the same measurement range (scale).
The other instrument is not properly calibrated The tendency is to believe the old measurement rather then the new. If all is set up correctly you should assume that the Magnum gives you correct information.
Pumps do not always deliver the specified capacity Magnum is correct
Doubling the number of pumps does not double the flow Magnum is correct
The pipe is not completely filled Magnum is showing more flow then really present because it assumes a filled pipe. Move the meter to a different location.

The meter shows zero when there is flow
Sensor orientation is off point arrow on top end of sensor in flow dirction.
Sensor, cable, or transmitter damaged return for repair

The display stays blank or shows only partial caracters
Display has been damaged  return for repair

4-20mA output seems incorrect
Using external power source to drive 4-20mA circuit  Magnum has a self powered 4-20mA output. Do not use an
external power source.

Magnum is slow to react to flow
Filter and/or window has been set too high Reduce filter and/or window size



- attach the sensor cable to the transmitter while it is powered up.
- cut or modify the sensor cable. It is part of the calibration.
- submerge the transmitter.
- expose the connector end of the sensor cable to moisture.
- remove the snap-ring from the universal mounting mechanism unless the tap valve is securely closed.
- expose the cable or sensor to temperatures above 100 C unless they are part of the High Temperture model.