PDIT fire water pump

Hello,

I have a fault on a differential pressure transmitter of a fire water pump. Indeed, by measuring the voltage at the level of the transmitter; it was zero (0 VDC) instead of 24 VDC. We replaced replacing the 1715-IF16 board to which my transmitter was connected. By measuring again the voltage coming out of our PLC card, we found 19 VDC; and by connecting our differential pressure transmitter the voltage drops to zero.
Does any of you have any idea about the cause of this brutal tension? And can he have an idea about the cause of this defect in order to remedy it?

Thank you

Is it a two wire transmitter? Or is it a pressure switch?

What you describe is a sign that the pressure transmitter is shorted. Have you checked the connections to ground?

I've troubleshooted some of that 24VDC stuff before. A good method for me is to first take the wire off the card and check voltage. If it's 24 or more, then good, if not check what's going on with the card. Second, if it's good, put the wire back on and take the wire OFF the transmitter. Check voltage. If 24, then good, if not, check the wire for a pinch or a short. If good, replace wire on transmitter. If not good, then like cardosocea said, probably a bad transmitter or ground. Ground connections are important in 24V.