GLS Compact Composite Sampler

It's a great little sampler!

GLS Compact Composite SamplerThe GLS Sampler is designed for general purpose or priority pollutant sampling in municipal and industrial applications where a full-size sampler is too large. It collects composite samples, based on time or flow intervals, in 1- or 2.5-gallon glass or polyethylene bottles, or in 2-gallon disposable ProPak® bags​

With GLS's simplified programming, setup takes less than a minute. In the field, the operator simply calls up the program with two keystrokes, presses the "go" button - and the sampling routine begins. You can also key in an alternate program in the field, without losing your stored program.


When you purchase instruments from Teledyne ISCO, you not only receive innovative, high quality products, you also receive excellent customer service and product support. Your initial purchase is only the beginning of Teledyne ISCO's ongoing commitment to their customers.


Sampler Selection GuideBrochure
Sampler Source BookBrochure
ISCO GLS Compact Composite Sampler DatasheetDatasheet
Isco Stormwater Monitoring GuideOther
GLS Compact Sampler Pocket GuidePocket Guide
GLS Sampler Safety and Certification SheetSafety and Certification Sheet
GLS Compact Sampler User ManualUser Manual


​​​​​​​​​​​​​GLS Sampler

Size (Diam. x Height): 16.5 x 26.5 inches (42 x 67 cm)
Weight: 24.5 lbs (11.1 kg) (dry, less battery)
Sample bottles: 1.0 or 2.5 gallon polyethylene or glass container.
Power Requirements: 12 volts DC. (Supplied by battery or AC power converter.)


Intake purge: Purge before and after each sample.
Tubing life indicator: Provides a message to change pump tubing.
Intake suction tubing: Length 3 to 99 ft. (1 to 30 m), Vinyl or Teflon® lined, ID 0.375 in. or 0.250 in
Pump tubing life: 2,000 samples
Typical repeatability: ±10 ml
Maximum lift: 26 ft. (7.9 m)
Typical line velocity @ Head height: 2.9 ft./s @ 3 ft; 2.5 ft./s @ 10 ft; 1.9 ft./s @ 15 ft. (0.76 m/s @ 0.9 m; 0.76 m/s @ 3.1 m; 0.58 m/s @ 4.6 m)
Sample presence detector: Non-wetted, non-conductive sensor detects when liquid sample reaches the pump to automatically compensate for changes in head heights.
Operational Temperature: 32° to 120°F (0° to 49°C)


Enclosure: NEMA 4X, 6 IP67
Program storage: 1 sampling program (in non-volatile ROM)
Flowmeter signal input: 5 to 15 volt DC pulse or 25 millisecond contact closure.
Number of composite samples: Up to 500 maximum
Clock accuracy: 1 minute per month, typical, for Real Time Clock
Sampling modes: Uniform time, flow. (Flow mode is controlled by external flow meter pulses.)
Sample frequency: 1 minute to 9,999 minutes, in 1 minute increments. 1 to 9,999 flow pulses.
Sample volumes: Programmable 10 to 9,990 ml in 1 ml increments
Controller diagnostics: Tests for RAM, ROM, pump, and display

​For a full list of product specifications, see the datasheet.



Standard Features

  • Overall diameter is only 16.5 inches (42 cm), so GLS fits easily into manholes as small as 18 inches (46 cm), and also easily drops into most offset manh​oles.
  • Dry weight is less than 25 lbs (12 kg), the lightest sampler in the ISCO line.
  • Hinged handle makes one-handed carrying a breeze.
  • The patented LD90 Liquid Presence Detector and ISCO pump revolution counting system deliver accurate, repeatable sample volumes time after time.


  • Wastewater effluent
  • Stormwater monitoring
  • CSO
  • Permit compliance
  • Pretreatment compliance

Options and Accessories

  • Composite Sampling bottle configurations (1-gallon or 2.5 gallon glass or plastic; 2 gallon ProPak disposable sampling system)
  • Power sources
  • Suction lines and strainer