One rod probe 11961Z

Summary

Product identification

• Product Name: Rod probe 11961Z
• Description: Partially insulated rod probe for use in conductive liquids.

Application

The 11961Z rod probe is used for conductive level limit detection in process or storage tanks for various liquids.

• Conductivity: As of 0.02 mS/cm
• Temperature: –200 °C to 250 °C
• Pressure: –1 to 160 bar
• Functionality:
  • Overfill protection (with line monitoring, also in Ex-area Zone 0)
  • Minimum or maximum level detection in tanks
  • Pump protection in pipes
  • Capacitive probe application (e.g., for overfill protection)
  • Two-point control

Benefits

• Suitable for aggressive media due to corrosion-resistant materials (rod and insulation).
• Can be used in steam boilers due to ceramic insulation resistant to steam and hot water.
• Suitable for high pressure or vacuum applications.
• Probe length can be shortened after installation.
• WHG (German Water Resources Act) + ATEX II 1/2 G approval.
• Connectable to switching units: FTW325, FTW470Z, FTW570Z, FTC325, FTC625.
• Safety features include line monitoring.
• Long operating life due to no moving parts in the tank.

Input

• Measured Variable: Change in resistance between tank wall and probe rod caused by the presence/absence of conductive product (binary limit value).
• Measuring Range: Dependent on probe mounting location; maximum probe length is 2000 mm.
• Input Signal: Alternating voltage supplied by a transmitter.

Output

• Switching Units: Nivotester FTW325, FTW470Z, FTW570Z, FTC325, FTC625.
• Output Signal: Relay output with floating change-over contacts for level alarms.
• Line Monitoring: Available on probes with WHG approval, integrated via a printed circuit board. It can be removed if the switching unit does not support line monitoring. With FTC325 and FTC625, line monitoring uses the PFM signal.

Power supply

• Electrical Connection:
  • Standard + ATEX: 2 terminals for core cross-section up to 2.5 mm² in the housing.
  • WHG (with line monitoring): 2 threaded connections for cable lug in housing with 2 m captive cable.
• Cable Entry: Cable gland Pg16 is suitable for cable diameters from 7 to 12 mm.
• Cable Specifications: Usual commercial cable (25 Ω per core). Screened cable recommended for strong electromagnetic radiation.

Operating conditions

Installation

• Mounting Location: Preferably vertical from above. For lateral mounting, the probe tip should point slightly downwards.
• Probe Length: Can be shortened to any length. Ensure insulation is not damaged and at least 20 mm of insulation is removed at the tip after shortening. No mechanical strain on the probe during shortening.
• Mounting in Piping: See diagram.

Environment

• Ambient Temperature Range: Depends on fluid temperature and permitted interior temperatures of the connection housing.
  • Standard & ATEX: –200 °C…+250 °C (depends on connecting cable). ATEX range is –200 °C…+200 °C.
  • WHG (with line monitoring): –20 °C…+65 °C.
• Storage Temperature: –20 °C…+65 °C (with line monitoring).
• Degree of Protection: IP55 as per EN 60529.
• Electromagnetic Compatibility: Refer to the connected Nivotester FTW or FTC limit switch for interference emission and immunity. EMC test procedures are detailed in TI241F/00/EN.

Process

• Medium Temperature Range: Varies based on ambient temperature and connection housing interior temperatures.
  • Standard: –200 °C…+250 °C.
  • ATEX: –200 °C…+200 °C.
  • WHG: –20 °C…+65 °C (with line monitoring).
• Conductivity: Minimum 0.02 mS/cm.
• Limiting Medium Pressure Range:
  • Standard: Up to 160 bar.
  • ATEX + WHG: Refer to explosion protection directives and certificate information.

Mechanical construction

• Design, Dimensions: See diagram. All dimensions in mm.
• Weight: Rod 1 m in length: 500 g.
• Wetted Materials:
  • Probe rod: Corrosion-resistant steel 316Ti (1.4571).
  • Process connections: Corrosion-resistant steel 316Ti (1.4571).
  • Partial insulation: Glazed ceramic.
  • Surround for partial insulation: Ni Fe 42 or Ni 99.6.
• Fitted Electrodes:
  • Diameter without insulation: 6.5 mm.
  • Maximum rod length: 2000 mm.
  • Minimum rod length: 100 mm.
  • Length of non-insulated area (tip): min. 20 mm.

Certificates and approvals

• CE mark: Device conforms to statutory requirements of EC Directives.
• Overfill protection: WHG (German Water Resources Act).
• Type of protection (ATEX):
  • Conductive: EC type-examination certificate TÜV 02 ATEX 1951 X.
  • Capacitive: EC type-examination certificate PBT 98 ATEX 2215 X.

Ordering information

The product designation requires specifying parameters such as Approval, Application, Process connection, Metal parts at ceramic, Rod material, and Length of probe.

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Disclaimer: This extraction may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror