Crowcon Vortex Installation, Operation And Maintenance

Vortex
60
APPENDIX A: GLOSSARY
This manual uses the following terminology, acronyms and abbreviations.
%LEL
Percentage of Lower Explosive Limit: a way of expressing the
concentration of a flammable gas.
%VOL
Percentage by Volume: the concentration of a gas expressed as a
percentage of the total volume of the mixture of gases. Also
abbreviated to v/v.
DCS
Distributed Control System
EMC
Electromagnetic Compatibility
FRAM
Ferro-electric Non-volatile RAM, this is the type of non-volatile
memory used in the Vortex node controller module.
Inhibit
Breaking the link between a channel and the associated outputs;
this is to avoid generating an alarm while testing or calibrating a
detector.
IS
Intrinsically safe: used to describe a device or circuit designed not
to produce a spark or thermal effect capable of igniting a
given flammable atmosphere.
LED Light Emitting Diode
Modbus Protocol used on RS485 and RS232 interconnections
PC Personal Computer
PCB Printed Circuit Board
PLC Programmable Logic Controller
ppm Parts per million: a measure of gas concentration when the
concentration is very small.
Relay Logic The interconnection between detectors and relays, handled by the
Node Controller Module.
RS232 Hardware serial communications standard between personal
computers and Vortex. The Vortex system works with the
Modbus protocol over this link.
RS485 Master-slave serial communications standard, used between PLCs
or DCSs and Vortex. The Vortex system works with the Modbus
protocol over this link. This standard is multi-drop, that is, a
number of Vortex systems can be controlled by a single master
system.
Sink (detector
configuration)
One side of a sink detector is connected directly to ground. The
relevant channel should be configured for the detector used. See
the detector specification sheet to see whether it is source, sink
or dual.
Source (detector
configuration)
One side of a source detector is connected directly to the supply.
The relevant channel should be configured for the detector used.
See the detector specification sheet to see whether it is source,
sink or dual.
SPCO Single Pole Changeover; a type of relay.
SWA Steel wire armoured, a type of cable which is enclosed in steel
wire for protection.
Zero The process of offsetting inputs to account for detectors which do
not give exactly 4mA.

Crowcon Vortex Specifications

General

Brand	Crowcon
Model	Vortex
Category	Control Panel
Language	English