Midas
®
Gas Detector
10-4
10.2 LonWorks
®
Software
10.2.1 LonWorks
®
Overview
LonWorks
®
is a communications protocol developed
by Echelon Corporation which facilitates peer-to-
peer communications in a control network. The
Midas
®
gas detector is available with an optional
LonWorks
®
interface.
The Midas
®
uses the Free Topology (FT) physical
layer which communicates at 78 Kbaud. Each FT
segment can contain up to 64 nodes and up to
2.7 Km of cable. Routers permit expansion of the
network to multiple segments.
The Midas
®
LonWorks
®
interface contains 2
functional blocks, 19 network variables and 2
network configuration inputs. It is designed for
compliance with LonMark guidelines version 3.2.
However, it is not LonMark certified. The LonMark
representation of the interface is shown in Diagram
10-3.
Information on LonWorks
®
can be found at
www.
echelon.com
. Information on LonMark can be found
at
www.lonmark.org
. Many commercial LonWorks-
compatible products can be found at
www.engenuity.
com
.
Diagram 10-3. LonMark Diagram
MIDAS LonWorks Gateway Device
Open-loop sensor Functional Block
nviReset
SNVT_lev_disc
nvoConc
SNVT_ppm_f
nv1
nvoFaultD
SNVT_lev_disc
nvoFaultS
SNVT_switch
nvoAlm2
SNVT_lev_disc
nvoAlmL
SNVT_lev_disc
nvoAlmThresh1
SNVT_ppm_f
nvoAlmThresh2
SNVT_ppm_f
nvoCellLife
SNVT_elapsed_tm
nviRelay1
SNVT_lev_disc
nviRelay2
SNVT_lev_disc
nviRelay3
SNVT_lev_disc
nvoMonState
SNVT_state
nvoAlmS
SNVT_switch
nvoGasSelection
SNVT_count
nvoNstat
SNVT_state
Mandatory
Implementation-Specific
Node Object Functional Block
nvoStatus
SNVT_obj_status
nv2
nviRequest
SNVT_obj_request
nv1
nvoChkSum
SNVT_count
nv3
Mandatory
Implementation-Specific
Virtual Function Block
nciMaxSendT
SNVT_elapsed_tm
cp22
nciMinSendT
SNVT_elapsed_tm
cp24
Summary of Contents for Midas
Page 7: ...Midas Gas Detector 1 1 1 Description ...
Page 9: ...Midas Gas Detector 2 1 2 Overview ...
Page 14: ...Midas Gas Detector 3 1 3 Default Configuration ...
Page 17: ...Midas Gas Detector 4 1 4 Installation ...
Page 41: ...Midas Gas Detector 5 1 5 Startup ...
Page 43: ...Midas Gas Detector 6 1 6 Operation ...
Page 53: ...Midas Gas Detector 7 1 7 Navigating Modes and Submenus ...
Page 74: ...Midas Gas Detector 8 1 8 Maintenance ...
Page 82: ...Midas Gas Detector 9 1 9 Pyrolyzer Module Options ...
Page 89: ...Midas Gas Detector 10 1 10 Optional LonWorks Interface Installation ...
Page 99: ...Midas Gas Detector 11 1 11 Troubleshooting and Fault Diagnosis ...
Page 102: ...Midas Gas Detector 12 1 12 REFLEX ...
Page 104: ...Midas Gas Detector 13 1 13 Internal Web Server ...
Page 106: ...Midas Gas Detector 13 3 Diagram 13 1 IPAddress setting in Windows XP ...
Page 129: ...Midas Gas Detector 14 1 14 Typical Installation Topologies ...
Page 132: ...Midas Gas Detector 15 1 15 Ordering Information ...
Page 136: ...Midas Gas Detector 16 1 16 Specifications ...
Page 139: ...Midas Gas Detector 17 1 17 Calibration and Bump Testing ...
Page 143: ...Midas Gas Detector A 1 A Modbus TCP Interface ...
Page 150: ...Midas Gas Detector B 1 B Gas Tables ...
Page 158: ...Midas Gas Detector C 1 C Warranty ...