0–2000 ppm, field adjustable to 0–5000 ppm

Indoor air quality

Non–dispersive infrared sensor

Dual lamp Virtual Reference™

Field selectable outputs and relay points

Proven history and quality

The 4GS is part of our gas sensor family for the low CO2 concentrations (0–2000 ppm field adjustable to 0–5000 ppm), typically used for indoor air quality applications. It uses a very proven, discriminating non–dispersive infrared (NDIR) sensor with a second lamp acting as a reference channel for improved longer term stability.

Combined with Sensata’s use of a second lamp as a reference channel and our patented software, the 4GS units only need to be calibrated every 3 years and attain excellent:

• long–term stability
• accuracy
• repeatability

Specifications
Sensing Method	Non Dispersive Infrared (NDIR)
Sampling Mode	Diffusion and/or pump capability
Range	0–2000 to 0–5000ppm (selectable in 100ppm increments with CAL-B-Key)
Accuracy (@25°C,760mm Hg)	±75 ppm if 0–1500ppm; ±5% if >1500ppm:
Pressure Effect	0.19% of reading per mm Hg
Repeatability	±16ppm
Warm–up	<90 seconds
Response Time	< 20 seconds to 63% of step change @500 ml/min flow rate
Calibration	None needed on install Zero and span recommended each 3yrs Easy in field with CAL-B-Kit
Output	0–10V dc standard (1K ohm impedance) User selectable to 0–5V dc with CAL-B-Key User selectable to 4–20mA with jumper (500 ohm max.) Liquid crystal display optional (2 line, alphanumeric, ppm & CAL-B-Key display) Relay optional (see below)
Relay Trip Points	Shipped as 1000 ppm (user selectable in 100 ppm increments with CAL-B-Key; resets 100 ppm below trip)
Relay Rating	10–500 mA @ 24 Vac or 30 Vdc
Input Power	24 V ac/dc, <3W
Temperature Ranges	0°C to +50°C (operating) -40°C to +70°C (storage) -20°C to +70°C (storage,display)
Humidity Range	5–95%, non–condensing
Case	3.84" x 3.84" x 1.10" (ABS, UL94VO)
Mounting Type	Hand–held (optional feature) or permanent
Instrument Type	Monitor
Measurement Type	Trace
Application	Ambient air monitoring
Notes	Indoor air quality, dual lamp, selectable relay points