Hi there,
We are trying to understand the exact behavior of the NI9216 (RTD) card.
As we know, there is no channel-to-channel isolation on the card (only channel-to-earth ground isolation), but how exactly a channel can affect other channels is still not well understood by us. In what ways can the RTD channels on the 9216 card affect each other?
Scenario:
1. Channels 0, 4, 6, 7 disconnected.
2. Channels 1, 2, 3, 5 connected to 4-wire RTDs.
3. All 4 connected channels were reading as expected.
4. Channel 3's sense wires were then open-circuited (i.e. RTD- disconnected).
a. Channel 3 still read the correct temperature, but with more noise.
5. Channel 2's excitation wires were then disconnected.
a. Channel 2 railed low.
b. Channel 5 spiked negative, but was reading normal after.
c. Channels 1 and 3 railed low.
Thanks a lot
