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Model PI51 & PI52 - PID Detector

Product information

  • The photoionization detector (PID) is used for the measurement of low (ppb) organic and inorganic species that can be ionized by the UV lamp (9.5, 10.6 & 11.7). Nearly 20,000 of these detectors have been sold worldwide since it was first released by HNU Systems in 1976. It has been used for the measurement of VOC’s in water (EPA method 602, EPA Method 50--, EPA Method SW846…, numerous OSHA methods), quality control… There are two Models that are described below:
  • The Model PI52 has a PID, a power supply for the lamp and bias and an electrometer. The electrometer output is 0-10 VDC. The customer needs a separate ADC channel to feed the signal into the GC’s data system. Alternately, PID Analyzers sells a data system (Model 50) that will feed the signal into a separate PC.
  • The Model PI51 has a PID and a power supply for the lamp and bias. Here, the customer uses the electrometer (FID type with a positive bias) already in the Gas chromatograph. This should already have the ADC connection to the customer GC data system.
  • The PID is one of the most sensitive detectors available for VOC’s. It has the widest dynamic range of any detector available (108) and does not require any support gases except the carrier.
Model PI51 & PI52 - PID Detector


Species measured

Organics (VOCs) and inorganic species that can be ionized by the UV lamp (9.5, 10.6, 11.7)

Detection limit

<0.5 ppb of benzene


> 5 x 107


2.5'' D x 5.5'' L

Electronics enclosure (PI52)

Weight: 3 lbs.
Size: -'' W x -'' L x -'' H

Electronics enclosure (PI51)

Weight: 0.40 lbs
Size: 4'' W x 5'' D x 1.25''H

Power consumption

< 2 amps @ 115V


10'' L x 3'' W x 2.25'' D


Easy to install

Improves separations and analysis of trace species.

Wide linear dynamic range

> 107

High sensitivity

pg or sub pg detection limits - most sensitive PID available


Is readily adaptable to any chromatograph.

Non destructive

Detectors can be run in-series.

Used by environmental agencies worldwide
Display (PI52 only)

Our 2 line by 16 character display can be backlit; used for range and background readings.


Our 16 bit ADC provides a resolution of 1 part in 64,000 and our signal algorithm minimizes noise by signal averaging in the msec range

Programmable Voltage output

0-10VDC (PI52 only)

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