• NBK Bypass Level, 1" NPT 230 PSI , Includes First 4" NBK-03N25

KOBOLD Instruments NBK-03N25 NBK Bypass Level, 1" NPT 230 PSI , Includes First 4"

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The KOBOLD NBK bypass level indicators are used for continuous measurement, display, and monitoring of liquid levels. The bypass tube is attached to the side wall of the tank. According to the laws of hydrostatic pressure, the level in the bypass tube will equal the level in the tank. A float, with embedded circular magnets, is located in the bypass tube and follows the liquid level, transferring the level in a non-contacting manner to a display attached to the outside of the bypass tube or to a sensing device.

Magnetic Roller Indicator: As the float passes by, the red/white rollers are rotated in succession by 180° around their own axes. The rollers change from white to red as the level rises and from red to white as the level falls. The advantage of ball display is the higher protection category, good visibility of 180° and higher vibration resistance with filled version. The level in a tank or a mixer is continuously displayed as a red column, even when the power fails.

Transmitter: To remotely sense the level, a transmitter with a chain of resistors or a magneto strictive transducer can be mounted outside the bypass tube. A continuous standard signal of 4 - 20 mA is generated by means of a fitted transmitter. This standard signal can then be displayed on analog or digital indicating devices. Optionally, HART® PROFIBUS®- PA or Foundation™ Fieldbus communication protocols are possible.

Universal Indicating Unit: A universal indicating unit, series ADI-1, can be mounted on the bypass tube to display and evaluate the standard signal (4 - 20 mA) generated by the transmitter.

Limit Contacts: One or more reed contacts, for point level sensing or for level control, can be mounted to the bypass tube.


  • Measuring Length: 18' Max over 18' Two-Part or Multipart
  • Pressure: Max. Class 1500
  • Temperature: - 40 to 750 °F (Ceramic rollers), -4 to 250 °F (POM-rollers), -155 to 390 °F (Ball display)
  • Viscosity: Max. 200 mm2/s Standard (Option: 460 mm2/s, only NBK-03)
  • Connection: ANSI Flange ½" - 2" & NPT Threads ½" - 1¼"
  • Material: 316-Ti Stainless Steel
  • Magnetically Coupled Magnet Roller or Ball Indicating Displays
  • Limit Contacts
  • Analog Output, HART®, PROFIBUS® PA, Foundation™ Fieldbus, & Digital Display Options


  • Storage tanks
  • Tanks on ships
  • Agitator vessel
  • Water tanks

Product Specifications

Rated PressureClass 150, PN 16
ConnectionNPT, Male Thread
Nominal Size1", DN 25
Ball MaterialPA - High Temperature Strength
Roller MaterialPOM
Display GlassPMMA
Carrier Frame MaterialAluminum, Black Anodized
ProtectionIP 54

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