Honeywell XNX Technical Manual

XNX Universal Transmitter
Section 1 - Introduction
10
1.1 Product Description
1.1.1 The XNX
®
Universal Transmitter
TheXNXUniversalTransmitterisacomprehensivegasdetection
systemdesignedtooperateinhazardouslocations
1
andutilize
multiplesensortechnologies,catalyticbead,electrochemical
(EC),orinfrared(IR)todetecttoxicgases,ammablegases,and
oxygendepletiongashazards�Eachtechnologyhasadedicated
personalityboard�
CatalyticbeadtechnologyisusedwiththeXNXmVpersonality
board�Catalyticbeadsensorsrespondtoawidevarietyof
combustiblessoaretypicallyusedforammablegasdetection�
ElectrochemicaltechnologyisusedwiththeXNX
electrochemicalboard�ECsensorsmeasuretoxicgasesin
lowconcentrations�TheXNXECsensorsemploythepatented
Reex™cellfaultdiagnosisroutine�Reex™checksforcell
presence,celldry-out,andcellopenorshortcircuit�Reex™is
automaticallyinitiatedbythetransmitterateight-hourintervals�
Itisalsoinitiatedonpoweruporsensorexchange�Inthe
eventofacellfailingthistest,asensorfaultcodeisdisplayed�
Reex™diagnosticsoccurintherstminutesofthepowerup
sequence�
InfraredtechnologyisusedwiththeXNXIRboard�IRsensors
opticallyabsorbgasesthatfallintotheinfraredspectrum�
Foradditionalinformationaboutanyofthethreesensortypes,
refertotheapplicabledatasheetforthesupportedsensorin
Figure1�
TheXNXUniversalTransmitteralsoallowsforanoptional
1
Therearethreemaintypesofgashazards:ammable,toxic,andasphyxiant�Aam-
mablegashazardisoneinwhichthereisariskofreand/orexplosion(e�g�,asituation
inwhichagassuchasmethane,butane,orpropaneispresent)�Atoxicgashazardis
oneinwhichthereisariskofpoisoning(e�g�,agassuchascarbonmonoxide,hydrogen
sulde,orchlorineispresent)�Anasphyxianthazardwouldincludeariskofsuffocation
throughoxygendeciency�(Oxygencanbeconsumedordisplacedbyanothergas�)
communicationboard�Therearethreetypesofboards:
relay,Modbus
®
,orFoundation
TM
Fieldbus�SeeSection1�1�2
Communicationsforadditionalinformation�

�
705
705HT
Sensepoint
Sensepoint HT
XNX Universal Transmitter
Multi-Purpose
Detector (MPD)
Catalytic Bead
Infrared Flammable
Infrared Methane/CO
2
CL
2
H
2
NH
3
O
2
ClO
2
H
2
S
NO
PH
3
CO HF
NO
2
SO
2
Personality Sensor Type Supported Sensors
IR Point and Open-Path Infrared Searchpoint Optima Plus, Searchline Excel
mV Flammable and Toxic
705, 705HT, Sensepoint, Sensepoint HT, MPD
(Catalytic Bead Flammable, IR Flammable and IR CO
2
)
XNX EC Toxic and O
2
Sensing
Electrochemical sensors, with Hot Swap, pre-calibrated
through Intrinsically Safe (IS) barrier
P
e
r
s
onal
i
t
y
S
enso
r
T
ype
y
T
T
S
u
ppo
r
ted
S
ens
o
r
s
Searchline Excel
Searchpoint Optima Plus
Figure 1. XNX Universal Transmitter and supported sensing technologies
TheXNXUniversalTransmitterrelieson4-20mAoutput,refreshed
atleasteverytwoseconds(oncepersecondistypical),inwhich
theoutputisproportionaltothegasconcentration�

Honeywell XNX Specifications

General

Brand	Honeywell
Model	XNX
Category	Transmitter
Language	English