Appendix I: Inputs/Outputs; Overview; Hardware Interface - NetComm NTC-220 User Manual

Appendix I: Inputs/Outputs

Overview

The NTC-220 is equipped with a 6-way terminal block connector providing 3 identical multipurpose inputs and
outputs as well as a dedicated ignition input. These inputs and outputs may be independently configured for
various functions, including:
NAMUR (EN 60947-5-6 / IEC 60947-5-6) compatible sensor input
▪
Proximity sensor input for use with contact closure (open/closed) type of sensors (PIR sensors,
▪
door/window sensors for security applications) with the input tamper detection possible (four states
detected: open, closed, short and break) by the use of external resistors
Analogue 0V to 30V input
▪
Digital input (the I/O voltage measured by the Analogue input and the software making a decision
▪
about the input state) with the threshold levels configurable in software
Open collector output.
▪

Hardware Interface

The interface of the 3 multipurpose inputs/outputs are based on the circuit diagram below
The Input/Output label is the physical connection to the outside world. There are protection devices and resistor
dividers to condition the signal prior to it going into the processor. The three labels to the right are the interface to
the processor. Output Enable activates the Transistor which provides an open collector (ground) output and can
sink 200mA at 230C. It is protected by a resettable fuse and transient protection diode. If used with the pull up
resistor, which can be activated by the Pull up Voltage Enable pin, then you can have a High or Low output rather
NTC-220 – User Guide
UG01028 v1.2 March 2019
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© NetComm Wireless 2019