Flow-X Prover Detector switch configuration

Flow-X Prover Detector switch configuration

The Flow-X requires a logical state transition—specifically, from 0 to 1—to start and stop counting during a proving run. This transition is based on logical state, not raw input voltage.

If the prover’s detector output is normally 24VDC and drops to 0VDC when triggered, and the Flow-X input is configured as normal (non-inverted), then the Flow-X interprets 24VDC as a logical 1 and 0VDC as a logical 0. In that configuration, the signal transitions from 1 to 0 when the detector is triggered, which does not initiate the counter. The counter would only start/stop when voltage is reapplied—i.e., when the signal goes from 0 to 1—so it behaves incorrectly.

To resolve this, the detector input should be inverted. This way, the Flow-X interprets 24VDC as a logical 0 and 0VDC as a logical 1. Now, when the voltage drops (detector triggered), the logical state transitions from 0 to 1—correctly starting or stopping the counter as expected.


Each prover manufacturer may have a different signal state indicating when the switch is made. You will need to look at how your ball switches and optical switches are setup in the prover and then verify the resting logical state is a 0 in the appropriate FlowX DI for the detector. If a prover wires the relay to the normally open side of the relay at one location and the normally closed side of the relay at another, the inverted signal setting would not be the same. 

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