KRF Capacitance Probes

APPLICATION:

KENCO Engineering's KRF Capacitance Probes are designed to provide reliable and consistent measurement of media level in your process. The Probes are constructed of a variety of materials, making them suitable for virtually any application.

To select the correct probe for an application, it is important to classify the process media as either Non-conductive (low dielectric) or Conductive (high dielectric)

Non-conductive Media (conductivity of less than 10 microsiemens/cm; a dielectric constant less than 10): solvent, oils, hydrocarborns, cryogenic fluids and most bulk solids fall into this category.

Conductive Media (conductivity of 10 microsiemens/cm or greater; a dielectric constant of 10 or greater): acids, caustics and fluids containing water fall into this category.

PRICIPLE OF OPERATION:

The Probe, in conjunction with the vessel wall and the process media (dielectric), from a capacitor. As the level of the media changes, a corresponding change in capacitance occurs. This change in capacitance is processed by the instrument and provides an output equivalent to the level in the vessel. In conductive media applications, the probe and the process media are the capacitive plates and the insulation (Teflon®) on the probe is the dielectric.



COMMON APPLICATIONS:

• Oils, Solvents and other hydrocarbons
• Acids & Caustics
• Slurries
• Liquid Interfaces
• Bulk Solids
• Water
• powders
• Cryogenic Fluids

• Heavy-duty construction on all probe types
• Leak-proof, self adjusting process seal (bare & insulated styles)
• Field adjustable (shorten) probe length (bare & flexible probes)
• Cryogenic probes - specifically designed for cryogenic fluids
• Wide variety of construction materials

SPECIFICATIONS

PROBE TYPES:
A typical probe consists of a probe rod / cable, a processs connection and a seal. There are four basic probe families: Bare, Insulated, Flexible and Cryogenic. Each probe is designed for specific application conditions.

* To Select The Appropriate Probe For Your Application CLICK HERE To View The Probe Selection Flow Chart In PDF Format.

NON-CONDUCTIVE MEDIA PROBES:

Bare Probes (Models P1A & P1F)

Bare Probes are used in non-conductive media. The rods are 1/2" in diameter, and have a maximum length of 234". The probes can be bent (Model P1F) to 90° at the factory. A bent probe can provide a vertical configuration, when a horizontal connection is used. Typical process connection is 3/4" NPT.

Bare Stillwell Probes are used in non-conductive media to provide a linear reference to the process media in applications involving non-paralell vessel walls (bullet tanks), non-metallic vessels, or when the probe is mounted more than 10" away from the vessel wall. They can also provide some damping in heavy turbulence processes. Use in fluids with a viscosity less than 250 centipoise. Typical process connection is 1" NPT.

Bare Reference Rod Probe (Model P1E) Bare Reference Rod Probes are used in non-conductive media to provide a linear reference to the process media in applications involving non-paralell vessel walls (bullet tanks), non-metallic vessels, or when the probe is mounted more than 10" away from the vessel wall. They are primarily used in media with viscosities from 250 to 20,000 centipose. Typical process connection is a 3" 150# ANSI Flange.

Cryogenic Probes (Models P4A, P4H & P4J) Cryogenic Probes are specifically designed for the measurement of cryogenic liquids. The P4A probe is used in a variety of cryogenic liquids. The P4H is specially designed for Liquid Hydrogen, and for higher resolution in other cryogenic liquids. The P4J is similar to the P4A, but with special materials designed not to ignite in liquid oxygen. Typical process connection is 3/4" NPT.

Insulated probes (Models P2A & P2F) Insulated Probes are used in conductive media. The probe consists of a 1/2" diameter metal rod, insulated with PFA Teflon® to a diameter of 5/8". The maximum length is 234". The probes can be bent (Model P2F) to 90° at the factory. A bent probe can provide a vertical configuration, when a horizontal connection is used. Typical process connection is 3/4" NPT.

Insulated Inactive Sheath Probe (Model P2B). The "Inactive Sheath" blocks the upperportion of the probe from registering any capcitance change. This is useful if the probe is horizontally mounted in a nozzle, preventing any debris or "build-up" from causing a false level indication. It is also used in liquid-liquid interface applications to block the air/oil interface, allowing the instrument to measure the oil/water interface. Typical process connection is 3/4" NPT.

Reference wire probes are used in conductive media to provide a reference to the process media in non-metallic vessels. This probe is limited to clean liquids, as any "build-up" on the wire will result in a measurement error. Typical process connection is 3/4" NPT.

Insulated Stillwell Probe (Model P2D) Insulated Stillwell Probes are used in conductive media to provide a reference to the process media in non-metallic vessels. They can also provide some damping in heavy turbulence processes. Use in fluids with a viscosity less than 250 cetipoise. Typical process connection is 1" NPT.

Insulated Reference Rod Probe (Model P2E) Insulated Reference Rod Probes are used in conductive media to provide ground reference in non-metallic vessels. They are primarily used in media with viscosities from 250 to 20,000 centipoise. Typical process connection is a 3" 150# ANSI Flange.

Flexible Probe (Model P3A) Flexible Probes are used in conductive media with a measurement range between 10 and 150 feet. The cable consists of a 1/4" stranded stainless steel cable, coated with Teflon® to a diameter of 5/16". typical process connection is 1" NPT.