Silopilot T FMM20

Summary

Product identification

• Product Name: Silopilot FMM20
• Description: Electromechanical level system for light bulk solids.

Application

• Measuring principle independent of physical properties like mass density.
• Measures level in bunkers and silos with powdered or fine grain bulk solids and liquids.
• Level measurements up to 42 m.
• Process temperature up to +150 °C (+302 °F).
• Suitable for aggressive atmospheres (e.g., acid or alkali vapors).
• Separation layer detection in fluids possible with suitable sensing weights.

Benefits

• Suitable for conditions where ultrasonic or radar level gauges may not be reliable.
• Precise level detection with an accuracy of ±2.5 cm or ±1 pulse.
• Compact device with 0/4 - 20 mA current output and other programmable signal outputs.
• Quick, menu-guided local operation with a 4-line text display.
• Fully electronic digital minimum fail-safe control, preventing sensor weight from entering silo outlets.

Measuring Principle

The FMM20 operates by lowering a sensing weight. When the weight contacts the medium, a motor tilts, which is detected by the electronics. The weight is then pulled up, and the distance traveled is measured and output. Pulses are generated every 2.5 cm of tape movement.

Measuring System

• Compact transmitter with integrated microprocessor-controlled electronics.
• Housing: Aluminium, optional coating.
• Sensing weights: Steel, Stainless steel 316TI, Plastic (PVC), Medium bag (Polyester), Oval float (Stainless steel 316TI). Variants for separation layer detection are available as accessories.
• Configuration: Via 4-line local display with plain and help texts.

Input

Measured Variable

• Distance from the flange to the product surface, minus a blocking distance.
• Calculated values include filling level, residual volume, and can be converted to volume or mass via linearization.
• Safety variables (security distance, safety distance) can be configured as warnings.

Measuring Range

• Maximum 42 m.

Block Distance

The block distance depends on the wiper length and selected sensing weight. Values range from 0.63 m to 2.02 m depending on the sensing weight type.

Input Signal

• Remote operation via two inputs (active or passive).
• Inputs, active: 12 to 24 V DC, minimum start pulse length 200 ms.
• Inputs, passive: Max. 0.3 W / 30 V DC, minimum start pulse length 200 ms.

Operating Frequency

• Measurement cycle: Minimum time depends on the measuring range. A minimum of 5 minutes per cycle is recommended.
• Tape running speed: 0.16 to 0.25 m/s.

Output

Output Signal

• Current output: 0/4 to 20 mA (active, programmable), maximum 22 mA.
• Relay outputs: 2 (optional 4), contact load max. 250 V AC / 6 A.
• Optocoupler output: Optional on devices with 4 relays, max. 30 V DC / 10 mA.

Programmable Relay Output Functions

• Counter pulse (corresponding to tape length).
• Reset pulse.
• Running up indication.
• Top position indication.
• Measuring indication (active measurement cycle).
• Alarm (switches in fault condition).
• Service interval.

Signal on Alarm

• Local display: Error symbol, code, and plain text.
• Current output: Minimum current value (≤ 3.6 mA or 0 mA), maximum current value (+10% or 22 mA), or programmable.
• Relay output: Alarm function.

Load (Current output)

• Max. 600 Ω.

Power Supply

Supply Voltage

• 90 to 253 V AC, 50/60 Hz.
• 20 to 28 V DC.

Power Consumption

• Max. 150 VA (for certain ambient temperature options).
• Max. 170 VA (for other ambient temperature options).

Power Supply Failure

• Configuration remains in memory.
• Current error logged.

Potential Equalization

• Must be connected to the external ground terminal.
• Recommended cable cross-section: 2.5 mm².

Terminals

• Max. 2.5 mm² (Supply voltage).
• Max. 1.5 mm² (Signal inputs, relay outputs, current output).

Cable Entries

• M20x1.5.
• Clamping range: 7 to 12 mm.
• Material: Plastic.
• Number of entries: 3.

Performance Characteristics

Measured Value Resolution

• ± 2.5 cm or ± 1 pulse (irrespective of measuring range).

Maximum Measured Error

• See Measured value resolution.

Influence Ambient Temperature

• Minimum time for a measuring cycle depending on the measuring range must be observed.

Mounting

Mounting Location

• Avoid locations where product buildup can cover the sensing weight or damage the tape.
• Consider product inflow and outflow points.
• Ensure the measuring path avoids fixtures and struts.
• Select wiper length to allow free movement of the sensing weight.

Installation Instructions

• Use structural measures for higher process temperatures near the installation site.
• Consider using a process connection extension.
• Outdoor installations may require weather protection.
• Ensure access for larger sensing weights.
• A G¼ female connection is provided for dust suppression by positive pressure.

Selection of Sensing Weights

Considerations:

• Must not sink into the product or slide off cones.
• Suitable for chemical properties and temperatures.
• Special types available.
• Normal weight: Steel or stainless steel, 1.5 kg.
• Plastic weight: Plastic, optional spike, 1.5 kg or 1.8 kg, max. +70 °C (+158 °F).
• Umbrella weight: Steel or stainless steel with Polyester, 1.9 kg, for light and loose bulk solids.
• Float: Stainless steel 316TI, 1.9 kg, for liquids and granulates.
• Medium bag: Polyester bag with stainless steel parts, 0.25 kg (empty) / 1.5 kg (filled), max. +150 °C (+302 °F), for bunkers with downstream mills.

Environment

Ambient Temperature

• -20 to +60 °C (-4 to +140 °F). Display readability may be affected outside this range.
• -40 to +60 °C (-40 to +140 °F) with self-regulating device heater.

Storage Temperature

• -40 to +80 °C (-40 to +176 °F).

Degree of Protection

• Enclosure closed: IP67.
• Enclosure closed with external start button: IP65.
• Housing open: IP20.

Electromagnetic Compatibility

• Interference emission: EN 61326, Electrical Equipment Class B.
• Interference immunity: EN 61326, Appendix A (Industrial).

Process

Process Temperature

• -20 to +70 °C (-4 to +158 °F).
• -20 to +150 °C (-4 to +302 °F).
• Maximum temperature at the unit from the bottom of the adaptor flange upwards is +60 °C (+140 °F).
• Process connection extensions may be needed for higher temperatures.

Process Pressure

• 0.8 to 1.1 bar absolute.

Heating

• Integrated heater recommended for ambient temperatures below 0 °C (+32 °F).

Mechanical Construction

Dimensions

• Housing dimensions vary based on selected wiper length (L): 225 mm, 515 mm, or 1015 mm.
• Process connection diameter minimum 95 mm.

Weight

• 11 to 17 kg (device only, without sensing weight).

Materials

• Housing: Aluminum (optional coated).
• Wiper: Aluminum/steel or stainless steel.
• Measuring tape: Stainless steel or plastic.
• Sensing weight: Varies by type (see Sensing Weights section).

Process Connection

• Flange: DN100 PN16 according to EN 1092-1.

Operability

Operation Concept

• Operator-oriented menu structure for commissioning, operation, and diagnostics.
• Menu guidance with help texts.
• Parameterization stored internally, retained after power loss.

On-site Operation

• Operating elements: 3 push buttons for configuration, 1 push button for starting measurements (optional external button).
• Display elements: 4-line, 20-character display. Contrast adjustable. Displays measured value numerically and graphically. Permitted ambient temperature for display: -20 to +70 °C.

Languages

• Deutsch, English, Francais, Japanese. Other languages available as an option.

Certificates and Approvals

• CE mark: Complies with applicable EU Directives.
• Ex approval: Data listed in separate documentation.
• RoHS: Complies with Directive 2011/65/EU and Delegated Directive 2015/863/EU.

Accessories

• Weather protection cover (stainless steel or aluminum).
• Adapter flanges for various pressure ratings and nominal diameters (e.g., DN150, DN200, 6", 8").
• Process adapters for smaller nominal diameters (e.g., DN50, DN65, DN80, 2", 3").
• Process adapter with spray water cleaning (DN100 PN16, for pressureless processes only).
• Sensing weight for interface measurement in liquids.
• Chain to increase block distance (up to 2 m).

Supplementary Documentation

• Operating Instructions (BA): BA00334F.
• Brief Operating Instructions (KA): KA01692F.
• Safety Instructions, certificates: Consult Ex documentation (XA) as relevant.

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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