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Model 201 Continuous Monitor

Product information

The Model 201-C PID is a flexible and versatile Analyzer. More than three thousand of these photoionization detector (PID) based Analyzers have been sold worldwide for applications ranging from carbon bed breakthrough, leak detection to stack and ambient air monitoring. This is attributed to the rugged and durable design that is characteristic of all PID Analyzers products. Several years ago, we added the flame ionization detector (FID) to the 201 series product line. Other continuous Analyzers in the 200 series include the Model 202 Infrared (IR) for Carbon dioxide, hydrocarbons, carbon monoxide, thermal conductivity detector (TCD), Model 204 and a Model 210 Zirconium Oxide Oxygen Analyzer. The addition of these new Analyzers greatly improves the capability and range of process analyzers from PID.

Model 201 Continuous Monitor


Detectors available


Measurement mode

Continuous Zero drift- Automatic compensation; <1% per month

Span drift

Auto cal each 24 hours

Wide range of response

from sub ppm on PID to % on the FID

Support gases

PID requires no support gases; FID requires H2 and zero air


7" HDMI Color Display

Standard output

WiFi, RS232


Rack (NEMA 2)-: 19" W x 11"H x 15"D

Weight: 22 pounds PID 24 pounds

FID Wall (NEMA 4) 23"W x 21"H x 7"D- PID 27"W x 21"H x 10"D- FID

Weight: -27 pounds PID

PID and FID Range

PID and FID Range PID range - 0.1 to 5,000 ppm > C4 plus, VOC’s, inorganic species such as H2S, NH3, I2, PH3, AsH3, Sulfur etc. FID Range- 1- 20,000 ppm, 1-2,000 ppm VOC’s (hydrocarbons only)


Automatic Restart

In the event of a power outage, the instrument will automatically restart

Low cost of ownership

The long lifetime of the analyzer coupled with the minimal level of maintenance results in a low cost of ownership

Wide operating range

with no range changing necessary- 16 Bit ADC Push button Automatic calibration

Push button Automatic calibration

automatically adjusts response

Autozero for PID

Automatically injectszero gas & adjusts auto zero for FID

PID- lamp out alarm

FID-flame out shuts off hydrogen and provides alarm

RS232 digital output; 0-1 VDC analog

output, WiFi, Bluetooth

Up to 6 dual setpoints

that are programmable- can be used to shut down a process, Range_ ppm 0-50, 0-500 0-5,000

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