Gas Detection Controllers

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HA20 Digital Gas Controller

2-channel gas detection system with configurable control, flexible application and user-friendly operation.
Features and Benefits
  • Accepts inputs from up to two 4-20mA sensors transmitters
  • Touch & magnetic keyboard for nonintrusive operation
  • 3 independent alarms per channel
Quick Specs
  • Display: 128 x 64 pixel graphic LCD with backlight displays
  • Power requirement: 100-240 VAC / 24 VDC
  • Operating temperature: -25°C to +50°C
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Product Overview

The HA20 digital gas controller provides simultaneous display and alarm functions for two sensor transmitters, along with user-friendly operation and configuration flexibility.

The HA20 accepts sensor inputs for gas concentration and other atmospheric data. It can function as a standalone device or can be integrated into a fire and gas system. The controller features NEMA4X enclosures and meets Class I, Div. 2, Groups A,B,C,D requirements. Explosion-proof wall mount packaging options are also available.

The controller features a large, graphic LCD readout that displays monitored data as bar graphs, trends and engineering units. A touch-and-magnetic keypad allows for non-intrusive operation in potentially hazardous locations. Cal Mode offers pushbutton zero/span calibration for direct sensor interface applications. Authorization Mode allows locking of critical configuration variables.

Other standard features include Modbus TCP/IP communications, three independent alarm levels per channel, alarm relays, flexible mounting options and 4-20m inputs. The 4-20mA inputs are ideal for interfacing to sensor transmitters that may be long distances from the controller. 24 VDC @ 8 watts provides external device power. The controllers accept inputs from two 

Additional Features and Benefits:

Enhanced Technology

  • Accepts inputs from up to two 4-20mA sensors transmitters. Generates 24 VDC @ 8 watts external device power

Fit for Purpose

  • CSA certified to C22.2 NO. 152 for combustible detection and Class I, Div. 2, Groups A,B,C,D CE
  • Touch & magnetic keypad for nonintrusive operation in potentially hazardous locations
  • NEMA 4X (Div. 2 certified) and Explosion-Proof wall mount packaging options available
  • Three standard SPDT common alarm relays for HORN, HIGH, WARN or FAULT

Advanced Communications

  • 3 independent alarm levels per channel. Relay Acknowledge feature allows silencing of external audible devices during existing alarm conditions
  • Graphic LCD readout displays monitored data as bar graphs, trends and engineering units. Alarm LED’s flash when new and become steady after acknowledged
  • Cal Mode offers pushbutton zero / span calibration for direct sensor interface applications. Authorization Mode allows locking of critical configuration variables
HA20 Digital Gas Controller for hazardous areas - Honeywell Analytics


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