Geneq > Environnement > Sonde d’interface

Sonde d’interface
Modèle 122


Solinst Oil/Water Interface Meters give clear and accurate measurements of product level and thickness in wells and tanks. Determination of both light (floating) non-aqueous phase liquids (LNAPL) and dense (sinking) non-aqueous phase liquids (DNAPL) is quick and easy. The factory-sealed probes are pressure proof and tapes are available in a range of lengths from 65 - 1000 ft. (20 - 300 m). The 5/8" (16 mm) diameter P1 Probe allows easy access through tight spaces and into narrow wells. The Probe is designed for use in various monitoring applications.

Hazardous Locations Use
The Model 122 Interface Meter has been approved by the Canadian Standards Association (CSA) for use in explosive environments. It is suitable for use in hazardous locations Class I, Groups C&D. The grounding strap is a safety essential when the meter is used in potentially explosive environments. It also ensures that the electronics are properly protected.

Accurate, Reliable, Robust
  • Designed for rugged field use
  • Stable electronics with automatic circuitry testing
  • Tape uses stranded stainless steel conductors:
    • non-stretch; does not corrode
    • resists kinking and breaks
    • easy to repair and splice
  • Sturdy free-standing reel with carrying handle

High Quality Design
The state-of-the-art electronics include automatic circuitry testing when the 'On' button is used; 120 hours of on-time battery life; clear signals; and high accuracy. Infra-red refraction is used to detect liquids and conductivity to distinguish water. Both optical and electronic sensors are precisely aligned at the same zero point. A steady light and tone indicate product. Water is indicated by intermittent signals. The factory sealed probe does not need to be accessed by the user. An integral stainless steel shield protects the sensors. It is set permanently into place, yet allows for easy cleaning. The circuits are powered by 2 standard 9V batteries which are housed in easy-access drawers in the faceplate of the reel.

Features
  • Sensor accuracy to 1/200 ft. or 1.0 mm
  • Certified intrinsically safe
  • 5/8" (16 mm) diameter probe
  • Easy access batteries: minimum 120 hours of life
  • Automatic shut off after 10 minutes
  • Inexpensive, simple repairs
  • 3 year warranty

Operating Principles
Product (Non-conductive liquid) = Steady light and tone Water (Conductive liquid) = Intermittent light and tone To detect liquids, Solinst Interface Meters use an infra-red beam and detector. When the probe enters a liquid the beam is refracted away from the detector which activates an audible tone and light. If the liquid is a non-conductive oil/product the signals are steady. If the liquid is water (conductive liquid greater than 50 μS/cm), the conductivity of the water completes a conductivity circuit. This overrides the infra-red circuit, and the tone and light are intermittent. Both sensors use exactly the same zero point, giving accuracy as good as 1/200 ft. or 1.0 mm. The high accuracy enables the sensors to detect the slightest sheen of oil on the surface of the water; this is indicated by a rapid intermittent tone.

Probes
122 P1: 5/8" diameter (16 mm) stainless steel. The beam is emitted from within a cone-shaped tip made from rigid polyurethane. The tip is protected by an integral stainless steel shield. This probe is excellent for the vast majority of product monitoring situations. 122M Probe: 5/8" diameter (16 mm) stainless steel. Similar to the P1 but shorter. Model 122 P1 and 122M Probes

Tape
The easy-to-read markings on the tape are permanently heat-stamped into the tape. The dog bone shaped tape avoids adherence to wet surfaces in wells. It is resistant to most chemicals, and the smooth surface of the tape is easy to decontaminate, and easy to handle.

M2 Feet and tenths: with markings every 1/100 ft.
M3 Meters and centimeters: with markings every mm.
N2 and N3 As above, but on the narrow 1/4" (6 mm) tape for the 122 Mini Interface Meter.

Obtaining Product Measurements
To measure the thickness of a product layer, lower the probe into the well until the signals activate. If there is an oil/product layer on the top of the water (LNAPL), the light and tone will be steady, indicating an air/product interface.

Read the depth off the permanently marked tape. Lower the probe further into the water, where the signals become intermittent, then pull back up and take a reading at the product/water interface. The thickness of the product layer is then determined by subtracting the first reading from the second.

If there is only water in the well and no product, there will only be intermittent (water) signals.

The presence or absence of dense (sinking) non-aqueous layers (DNAPL) is determined by continuing to lower the probe to the bottom of the well.

If the steady tone and light return, this indicates a non-conductive liquid. Measure the depth and continue lowering the probe until it touches bottom and the tape goes slack.

To determine the thickness of the DNAPL layer, subtract the first reading from the bottom depth.

Standard Equipment
Each standard meter is provided with a grounding clip, cleaning brush, a convenient carrying bag with shoulder strap, and a tape guide/datum. The tape guide may be used to provide support for the reel on the well casing. It acts as a datum allowing repeatably accurate measurements; ensures that the probe hangs in the centre of the well; and protects the tape from damage. It is essential to use the grounding clip to ensure safety and proper function of the electronics in all applications.