Just tap the electromagnetic flowmeter twice – why?
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We have a Rosemount electromagnetic flowmeter here that often fails to display the flow rate, even though there is power supply; tapping on the meter’s body makes it work properly. The issue of loose wires has been ruled out – what could be causing this problem?
Just like black-and-white TVs; I’ve forgotten the specific reason
I guess the internal wiring is loose; it made contact after being tapped a bit.....
A tap is enough; it’s usually related to poor contact and weak soldering.
1. There is dirt or scale at the electrodes inside the gauge. 2. There is poor contact inside the instrument (not in the case of Rosemount, I think). I can’t think of anything else……
It’s either an internal wired connection issue, or the magnets are covered; we’ve encountered this problem as well with Rosemount integrated units – the display value increases when tapped and decreases when not tapped. The wiring has been checked and is properly secured; it’s unclear what’s going on inside, and there is water in the pipeline. The specific reason is not entirely clear at the moment
Is there a loose capacitor on the circuit board? It’s recommended to check it carefully; I’ve encountered this issue before as well.
I agree with the analysis of the friends above: 1. Consider that the electrodes are dirty or scaled; 2. Consider that there may be loose connections or soldering defects on the internal circuit board. Overall, I lean more towards the second option; therefore, it is recommended to take it apart and send it back to the manufacturer for a thorough circuit inspection. If the conditions aren’t right, it will have to be done at some other time.