Microscan EZ Match, User Manual

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EZ Match User’s Manual
Using an External Trigger
Appendix G — Using an External Trigger
Two types of inputs are used on Microscan readers. 5 volt devices have NPN trigger
inputs. 10-28 volt devices have optoisolated inputs and outputs.
5 Volt Devices
To trigger a 5 volt device, the input has to be pulled down to “signal ground” (NPN). This
can be done by relays or by a transistor-sourced signal. If a 5 volt device is used in combination
with an IC-332, it must be connected as a 10-28 volt device.
10-28 Volt Devices
To trigger a 10-28 volt device, a small amount of current needs to flow from “T” to
“Trigger –”. If a PNP source is used, “Trigger –” must be connected to “signal ground”. If an
NPN source is used, “T” must be connected to the supply voltage.
Reader Sensor
Reader
Sensor
Reader
Sensor
Reader Sensor
Reader Sensor
PNP NPN