PLC not reading pulse input from Flow Meters

[widelto]

SITRANS MAG 6000 I/6000 I Ex de

See attached figure

Taken from:
https://support.industry.siemens.co...6000-i-6000-i-ex-de?dti=0&pnid=17321&lc=en-WW

RL is your PLC input, you can add a resistor if you want it.

Please take into account pulse frequency I do not know if your PLC DC inputs are fast enough to handle these pulses.

 

[Dawsam445]

Thank you all for your input and suggestions!! Ended up replacing the power supply and 6 or 7 meters started pulsing almost immediately. Seems like the rest may be configuration or wiring issues with the individual meters. Should hopefully be able to get most figured out here soon. Thanks again for everything!

 

[JohnJPhillips]

Is your DI card rated for the speed at which you are trying to see pulses? Often a flow meter will require a high speed input card.

I've been installing a ton of those lately. You can usually circumvent that by programming the flowmeter so that the pulse is more gallons per pulse. It would have to be very fast flow with an undersized flowmeter to need something like an allen bradley high speed counter.

Some plcs the pulse is too long and you need to use a one shot function so that the pulse only kicks once per count. Also my experience has been that the di card will read too many pulses unless the pulse length itself is too short for some older processes to catch on a scan. I'm talking mostly about magmeters and coriolis though to be clear.

Lots of potential problems with integrating flow meters.