It's just additional labeling to help people make correct encoder connections. The SRC, GATE, AUX, and OUT pin designations tell you about the connection on the counter itself. The A, B, Z pin designations tell you about the connection on the encoder side.
Encoder ch A should be connected to a counter's SRC pin, ch B to AUX, and ch Z to GATE. And that's what the redundant pin labels are trying to make clear.
-Kevin P
ALERT! LabVIEW's subscription-only policy came to an end (finally!). Unfortunately, pricing favors the captured and committed over new adopters -- so tread carefully.
