User's Manual

75
Document Number: 0100SM1401 Issue: 05-15
Digital I/O
Three channels of digital user inputs and outputs (Digital User I/O) can be read/written to via TView+ Diagnostics or SNMP.
Digital user I/O is available on the following products:
QB450 Full Duplex Radio
QH450 Hot Standby Full Duplex Radio
QP450 Hot Standby Half Duplex Radio
Information on how to control and monitor this I/O using TView+ Diagnostics can be found in Part G - TView+ Management
Suite - Remote Diagnostics & Network Controller.
SNMP object descriptions for digital I/O can be found within the advanced section of this manual.
Inputs
Three user Inputs are available. They have identical interface characteristics. Some form of switching contact (i.e: switch,
relay) is normally used to change the state of the input. Both an isolated and non-isolated input configuration is possible.
Typical input drivers include: dry contact (relay), electronic control or driven control. Each input can support either type of driver.
Reading the status of a user input while the circuit is CLOSED will report the input as being ON.
Reading the status of a user input while the circuit is OPEN (or not connected) will report the input as being OFF.
Typical Input Drivers
Outputs
Three user outputs (open collector) are available. They have identical interface characteristics.
Power Specifications
Maximum Voltage allowed across each output is 30V DC.
Maximum current allowed through each output is 1A. External resistors or a current limited supply should be used
to keep the current below this value.
When the OUTPUT is OFF, The circuit will be OPEN. When the OUTPUT is ON, The circuit will be CLOSED.
Dry Contact
Electronic
Control
5V or
Floating
Driven Control
Load
0V to 30V DC Supply
V
+ -
Part F – Quick Reference Guide