Technical Details For Netbotz Dry Contact Interfaces
NetBotz version 2 sensor
Technical Details For Dry Contact Interfaces
-The technical details for dry contact (contact closure) interfaces are as follows.
-All current on a dry contact connection is direct current (DC).
-The minimum is 0.3v and the max is 3.3v.
-The two wires correspond to +3.3V output from the NetBotz Appliance and an A/D input (with a 10K pulldown).
-When the A/D is "floating", it pulls to 0V. When the two are "shorted", the A/D winds up reading just below 3.3V.
-By default, NetBotz is treating values below 0.3V as "open" and above 0.3V as "closed".
-It is VERY IMPORTANT not to "push in" a voltage from another device.
-Dry contact devices, either due to using physical relays or opto-isolators, open or close the circuit between the two wires without actually driving a voltage into the wires, which eliminates the need for a common ground reference.