WL550 Oil Water Interface Meters

Price$3,724.00 (US Only)


In Stock 0 - Available for Backorder

Global Water’s WL550 Oil/Water Interface Meters measure the depth and thickness of floating (Light Non-Aqueous Phase Liquids or LNAPLs), sinking (Dense Non-Aqueous Phase Liquids or DNAPLs) hydrocarbons and water in monitoring wells as small as 1/2 inch (12.5 mm) inner diameter using an optical probe for industry-leading accuracy.

  • Overview

    Using state-of-the-art electronics, the WL550 Oil Water Interface Meters deliver reliable, rock-solid performance in the field. This allows more readings and more accurate measurements compared to other similar oil-water interface meters. The oil-water interface probes use infra-red refraction to detect hydrocarbons and conductivity to detect water.
    The oil-water interface meter's triple-sealed probes do not need to be accessed by the user. Using "smart electronics," the oil-water interface probes will ignore any damage to the optical lens and continue to perform. Similar to a water level meter, the WL550 Oil Water Interface Meters produce a solid tone in water, and an intermittent light and tone indicate the presence of hydrocarbons. This system doubles the oil-water interface meter's battery life and provides better overall performance.

    Key Features:

    • Precision measurement, simplicity, and durability
    • Highest quality steel core engineering tapes
    • Automatic sleep function
    • Smart electronics ignore severe scratches, condensation, and dripping oil
    • Easy access battery drawer
    • Audio alert beeper and LED indicate contact with the water

    The standard oil-water interface probes are 5/8 inch (16 mm) in diameter; however, a unique 7/16 inch (11 mm) probe for ½ inch (12.7 mm) ID wells is available. Impact proof oil-water interface probes resist all solvents found in environmental monitoring. The oil-water interface meter's probes are far more chemically resistant than probes using polyurethane or polysulfone optics. Stainless steel shrouds protect and secure the oil-water interface probes while being more durable than plastic shrouds. The oil-water interface meter's optical sensor and electronics work together to ignore minor or severe scratches. Setting a new industry standard, the WL550 oil-water interface probes will detect a 0.02 inch (½ mm) layer of hydrocarbons versus the typical 0.12 inch (3 mm) hydrocarbon detection limit. The oil-water interface meters can be recalibrated to 0.04 inch (1 mm), 0.08 inch (2 mm), or 0.12 inch (3 mm) hydrocarbon detection limits for user preference. The water sensitivity can be increased on the oil-water interface meters to ensure quick readings or reduce to avoid bridging when the water contains many dissolved solids, giving the user ideal performance in all field conditions.

    Designed specifically for measuring hydrocarbons and organic solvents, the oil-water interface meter tapes are four times more accurate than common flat white TV cable-type tapes. Oil-water interface meter tapes use the highest accuracy yellow measuring tapes available (0.008% or better guaranteed). All oil-water interface meter tapes meet or exceed federal specification US GGG-T-106E(U.S.A) or EEC CLASS ll (Europe). The tape zero points and probe zero-point coincide within 0.01 inches (0.254 mm) versus 0.06 inches (1.52 mm) found on most industry-standard oil-water interface meters. Common flat white tapes use twisted stainless steel wires that can untwist and lengthen up to 1/2 inch (13 mm) per 100 ft (30.5 m) from the oil-water interface meter cable's own weight. The unique flat spring steel measuring tape of the WL550 Oil Water Interface Meter has a breaking strength of 297 pounds (135 kg), allowing it to hang straighter than standard tapes and not stretch (less than 0.001 inches (0.025 mm) under a 35 pound (16 kg) load. A clear Kynar jacket covers the oil-water interface meter's conductors protecting the graduations and numerical markings. The oil-water interface meter's Kynar covering is about 4-5 times harder (Rockwell hardness) than softer polyethylene white tapes making it less likely to be cut or damaged. The WL550 Oil Water Interface Meter tapes are chemically resistant to all chemicals found in environmental monitoring and will not become softer when exposed to gasoline and other solvents. The covering also makes it easier to decontaminate Global Water's oil-water interface meters than meters with embossed tapes.

  • Specifications
    WL550 Oil Water Interface Meter Specifications  
    Tape Graduation 1/10 ft and 1/100 ft (1 cm and 1 mm)
    Tape Material

    Flat spring steel with clear kynar jacket

    Detection Limit  0.02 inch (0.5 mm) layer thickness

    0.008% or better


    Audible buzzer and light

    Battery 9 V battery

    Battery Life

    180 hours

    Auto Shut Down

    Unit powers down after 10 min

    Probe Diameter

    5/8 inch OD (16 mm)

    Shipping Weight 300 ft (100m) tape: 9 lbs (4 kg)

    Shopping Size

    12 x 14.5 x 8.5 inch (31 x 37 x 22 cm)

  • FAQs

    What makes the WL550 different from other YSI water level instruments?

    • It is a water level sounder used for well water level monitoring, along with measuring the depth and thickness of floating (LNAPLs), sinking (DNAPLs) hydrocarbons in water
    • it has the highest quality tape on the market along with a field-replaceable sensor
    • The product is battery powered and will notify the user when the sensor has made contact with the water or hydrocarbons

    What applications is the WL550 best suited for?

    The WL550 is suited for aged wells, where you need to measure the depth and level of water within that particular well along with detecting and measuring depth and thickness of hydrocarbons.

    Ideal for wells that may be crooked, have internal debris, or well intrusions along with detecting tank leakages.

    How will I know water depth and or oil/water level detection?

    The WL550 contact sensor will make a noise and the LED sensor will light up and once contact is made with well water or hydrocarbons reel in the tape and record your well depth

    What type of tape lengths are available?

    Tape length ranges: 100’, 200’,300’,500’,650’,750’,1000’, and 2000’

    Why use the WL550 Oil-water interface meter over the WL500 well sounder and WL650 Sonic water level meter

    The WL550 is ideal for aged wells that are not entirely straight, have debris, or any well intrusions, and include any contamination of hydrocarbons.

    What are my power requirements

    Standard 9 Volt battery

    Does the WL500 have datalogging capability?

    The WL550 does not have the ability to record data but is extremely easy to use in the field for onsite measurements.

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