Greetings Smart Masses,
Thank you for adding me to the community.
I've become part of an unusual phenomenon involving an ABB drive and a IA1-D-VI analog input unit. Typically in a series circuit current stays the same and voltage drop across resistors changes based on E=I*R. I know this and as long as the total resistance is less than what the transmitter is rated for you'll read the same current anywhere along the circuit. However I have two devices displaying rpm's based on 4-20mA output of the drive and only one device is displaying the correct speed. The correct display has a resistance of 250 ohms. The other device is reading -1.8 mA. It has a resistance of 50 ohms.
How do I correct this?
Thank you for adding me to the community.
I've become part of an unusual phenomenon involving an ABB drive and a IA1-D-VI analog input unit. Typically in a series circuit current stays the same and voltage drop across resistors changes based on E=I*R. I know this and as long as the total resistance is less than what the transmitter is rated for you'll read the same current anywhere along the circuit. However I have two devices displaying rpm's based on 4-20mA output of the drive and only one device is displaying the correct speed. The correct display has a resistance of 250 ohms. The other device is reading -1.8 mA. It has a resistance of 50 ohms.
How do I correct this?