Gasmonitor 1-16 channel control system

General Details

Gasmonitor Plus is Crowcon’s flexible 19″ rack-based control system. This microprocessor-controlled unit is used throughout the world, both onshore and offshore. Gasmonitor Plus can monitor up to 16 gas detectors or 32 fire zones per rack. Racks can be supplied separately, or built into wall mounting or floor standing enclosures.

A separate gas level display is provided for each gas detector. Gasmonitor Plus can be engineered into very large systems and tailored to suit individual site requirements.


Simple to use

  • All day-to-day functions are available from the front panel – push buttons for simple operation
  • Unique bar-graph display per channel – provides instant representation of gas concentrations
  • Common alarm LEDs on the display card – the whole rack status can be checked at a glance.

Flexible architecture

  • System is limitlessly expandable
  • Modular construction – ultimate customisation and minimal wiring
  • Industry-standard analogue outputs – will integrate fully with existing rack-mounted protection systems on-site
  • Optional relay modules – flexible and cuts down on configuration and monitoring cabling

Easy maintenance

  • Each channel is inhibited separately – plant safety is not compromised during checks
  • Routine calibration from front panel – reduces service overheads by half
  • One universal gas card – reduces spares holding
Size 483 x 133 x 294 mm (19.0 x 5.25 x 11.5 ins)
Weight 9.5 kg (21 lbs)
Enclosure material Aluminium alloy
Mounting Rack mounted (3u format).  Wall mounted and floor standing cabinets are optional, dimensions on request.
Channels 16 per rack
Operating temperature 0°C to +50°C (32°F to +122°F)
Humidity 0-95% non-condensing
Inputs Gas    2 or 3 wire 4-20mA (sink or source), or mV bridge
Fire – smoke & heat detectors, manual call-points   Maximum of 32 loopes per rack (ie 16 twin zone fire modules)
Outputs Analogue 16 x 4-20mA, max. load 960 Ohms or 1-5 V, min. load 100 Ohms
External audible/visual alarm drive Powered 24 V dc, max load up to 200mA for each alarm level.
Relays Type Up to 84 DPCO contacts rated 5 A @ 250 V ac, non-inductive load
Assignment – Common Alarm 1, Alarm 2, Alarm 3, Fault
– Per channel Gas alarms 1, 2 & 3, fire &
  – Voting Up to 16, configurable
                      – Relay modes Energised/de-energised,
latched/non-latched, time-delayed, pulsed
Digital communications DCS/PLC/PC/Local configuration link: RS-232
Event logging Built-in datalogger – data available via communication links
Panel indication Channel number: 4 lines x 20 characters back-lit LCD display
Gas reading: as above plus green LED bar-graph
Measurement units:  % LEL, ppm, % Vol, Fire
System fault – integrity watchdog:  Yellow LED
Alarm indication Visual – Alarm: 3 individual & 3 common alarms (red LED); Fault – individual & common fault (yellow LED); Inhibit – individual inhibit (yellow LED)
Power AC mains: 100 – 260 V ac 50/60 Hz external
DC: 27.6 V
Battery back-up: external
Approvals Low voltage directive – EN61010-1
RF immunity – EN 50082-1
RF emissions –  EN 50081-1