Technical Manual

XNX Universal Transmitter

Section 1 - Introduction

states. Two alarm levels can be set, allowing, for example, a level

1 alarm for the immediate area when a certain gas concentration

is detected and a plant-wide level 2 alarm when a greater gas

concentration is detected.

The maximum refresh rate of the relays is 2 seconds. See Set

Alarm Values for more information.

1.3.3 Modbus

The optional Modbus interface allows the XNX to connect to

a bus of devices and transmit data to PLCs or controllers.

(For more information, see the Modbus

Protocol Manual).

Connections to the XNX are made through a pluggable terminal

block on the Modbus interface circuit board. Modbus RTU

protocol uses ASCII/Hex protocols for communication.

Note: POD options are either relay, Modbus, or Foundation Fieldbus.

1.3.4 Foundation Fieldbus

Foundation Fieldbus is a digital communication system which

supports several types of messages. Unlike many traditional

systems which require a set of wires for each device, multiple

Foundation Fieldbus devices can be connected with a

single set of wires. Foundation Fieldbus overcomes some

of the disadvantages of proprietary networks by providing a

standardized network for connecting systems and devices.

1.3.5 XNX Accessories

Pipe Mount Kit

The Pipe Mount kit (1226A0358) allows the XNX to be mounted

to pipe from 2”-6” (50-150mm) in diameter. The kit includes the

pipe mount bracket, two carriage bolts, nuts, and lock washers.

Figure 8. Pipe-mounted XNX Transmitters

Calibration Gas Flow Adapter

The calibration gas ow adapter is used to apply calibration

test gas to the sensor. It attaches to the bottom of the sensor

and can be tted without removing the weatherproof cover. See

Section 3 - Calibration for further details on gas calibration.

Sensor Flow Adapter P/N

XNX EC S3KCAL

MPD 1226A0411

Sensepoint 02000-A-1645

705 00780-A-0035