Honeywell IF2, Руководство пользователя

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56 IF2 Network Reader User Guide
Use the Input Interfaces
Each of the four inputs is compatible with input signals of 10 to 36 VDC. Both the
high and low signal contacts are exposed and isolated to 1500 V. Input impedance
is 1.8 K ohms minimum.
GPIO Input Signal Descriptions
In a typical application, the IF2 senses input from an external control like a switch
and then starts a tag read operation.
There are three basic ways to connect input controls to the IF2 input interfaces:
• Supply the input interface with power from the IF2.
• Isolate the IF2 from the input power source.
• Use an open collector solid state drive from a remote device to control the
inputs.
For more information, see the next examples.
IF2 Powered Input
This is the simplest way to connect a control to an IF2 input interface. If the exter-
nal control device is a switch, you can connect one side of the switch to an IF2
+Input pin, and the other side of the switch to one of the +12 VDC sources. Ground
the corresponding -Input pin as shown in the next illustration.
IF2 Powered Input
Isolated Input Interface
Use this method to minimize noise induced by distance or grounding characteris-
tics. The isolated input avoids induced noise by referencing a remote input to chas-
sis return of the IF2. The next illustration shows how this method is wired.
Signal Description Min. Typical Max.
V
in
(High) High input voltage 10 V 24 V 36 V
V
in
(Low) Low input voltage -1 V 0 V 1 V
External
input
switch
+Input
+12 V
Ground
- Input