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Tank Gauging and Overfill Prevention etc.

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3100 MMP Multi Media Probe

3100 MMP Multi Media Probe

The 3100 MMP is a multi-section capacitance probe that provides Level, Temperature, and Water/Interface to custody transfer measurement accuracy. The MMP has four main configurations:

  • MMP-3100 UST (Underground Storage Tank)
  • MMP-3100 AST (Aboveground Storage Tank) Horizontal, Vertical Cylinders, etc.
  • MMP-3100 GAS (LPG – Liquid Petroleum Gas) Bullet Tanks
  • MMP-3100 MTT (Mobile Transportation Tank) Rail Tank Cars, Trucks, Barges


Theory of Operation

Its rigid construction makes it easy to install within most tank, process, and product applications. The MMP provides custody transfer measurement accuracy and field proven reliability (SIL2 rating).

This top mounted probe is made from one solid outer tube over the height of the tank, with multiple inner tube sections.  Slots in the outer tube allow product to freely flow in the space between the inner and outer tubes. Only the inner tubes are coated and the external tube is not insulated from the tank. This is an improvement over the initial CAP design.

The MMP may include up to 5 temperature sensors, class A, 100-ohm Platinum, four wire RTDs that provide the most accurate spot, and average product or vapor temperature. Unlike most capacitance probes, the MMP 3100 doesn’t depend upon a change in the product dielectric constant or temperature to work.

From an electrical point of view the MMP, includes multiple capacitances formed by an external solid pipe and multiple sections of internal pipe. All electrodes are connected to the Electronic Transmitter. Two optional 4-20mA analog outputs are available that can represent any chosen parameters.  An optional, external pressure transducer provides vapor pressure measurement and vapor mass calculations for pressurized liquid gas and clean product tanks. An additional sensor can be added to the solution to provide average product density.

Unlike most capacitance probes, which can only measure water at the bottom of the tank, the MMP measures any liquid interface at any level. Additionally, the MMP provides the level and volume of conductive products.

  • Product Measurement Section – provides level measurement and probe self-calibration
  • Water Measurement Interface – provides water or interface level measurement
  • Temperature – provides up to five multi-point spot RTDs
  • Options – Vapor Pressure, Mass, and/or Density



  • LPG Bullet Tanks
  • Underground Storage Tanks
  • Above Ground Storage Tanks
  • Tank Trucks
  • Tanker Rail Cars
  • Barge


Probe Lengths:Minimum tank height:39” (1 m)
Maximum tank height: 18’ (5.48 m)
Level:Accuracy - Product: Meets or exceeds API 3.1B requirements for Custody Transfer Applications. Typical value is +/- 1/16” ( +/- 1.5mm)
Level Accuracy - Interface:± 3/16” (± 4.8 mm)
Temperature: Accuracy:0.1° F (0.1°C)
Operating Conditions:Process temperature (in tank): -85° F to 482° F (- 65° C to + 250° C)
Environmental temperature (ambient): -40° F to 176° F (- 40° C to + 80° C)
Operating Pressure: 0 – 300 psi,
Material:Gauge Wetted parts:304 SST, 316L, and Teflon
Mounting flange:2”, 150 ANSI Flange - Standard,
Any process connection 2” or above are possible
Electrical:Intrinsic Safety:IS Barriers are required (Consult GSI)
Power Input:7-16 Vdc
Communication :IEEE RS 485 (Four Wires)
Wire Specification:Beldon 9773 or equivalent
Communications Protocol:MODBUS RTU
Approvals:UL, ULc, IEC, Others Pending
Shipping:Dimensions: 460” x 44” x 35“
Net Weight: 90kg - 199lbs
Gross Weight: 146kg - 322lbs

* Please note dimensions and weight may change depending on probe lengths and number of the probes in each single crate. For specific specs on your application, contact GSI.