Minicap FTC260

Summary

Product Identification

• Product Name: Minicap
• Model Numbers: FTC260, FTC262
• Type: Capacitive Point Level Switch with Buildup Compensation

Application

The Minicap is designed for point level detection in light bulk solids with a grain size up to a maximum of 30 mm (1.18 in) and a dielectric constant εr ≥ 1.6. Examples include grain products, flour, milk powder, animal feed, cement, chalk, or gypsum.

Versions

• FTC260: With rod probe for bulk solids and liquids.
• FTC262: With rope probe up to 6 m (20 ft); for bulk solids.

Available with:

• Relay output (potential-free change-over contact / SPDT) with AC or DC power.
• PNP output with three-wire DC power.

Benefits

• Complete unit with probe and electronic insert simplifies mounting.
• No calibration necessary on start-up.
• Active buildup compensation ensures an accurate switch point and high operational safety.
• Mechanically rugged design with no wearing parts, leading to a long operating life and no maintenance required.
• The rope probe of the FTC262 can be shortened for optimal matching to the measuring point, reducing stock requirements.

Measuring Principle

The Minicap functions as a capacitive sensor. A metal plate at the probe tip, insulation, an integrated counter-electrode, and the surrounding medium form a capacitor. Changes in capacitance when the probe is covered or free of medium trigger a switch. Active buildup compensation mitigates the effects of material buildup on the probe.

Measuring System

The Minicap is an electronic switch. The complete system includes the Minicap unit, a power supply, and controllers or switching devices.

Function Range

The applicability of the Minicap is related to the dielectric constant (εr) and density (ρ) of the material. Generally, it functions in:

• Foodstuffs with a density of 250 g/l and above.
• Plastic or mineral materials with a density of 600 g/l and above.

For materials with dielectric constants below the specified limits or low densities, alternative devices like the Soliphant FTM may be recommended.

Input

• Measured Variable: Point Level
• Measuring Range:
  • FTC260: εr ≥ 1.6
  • FTC262: εr ≥ 1.5

Output

• Output Signal:
  • DC, PNP transistor output:
    • Switching: PNP
    • Max current (Imax): 200 mA
    • Overload and short circuit protection.
    • Residual voltage at transistor at Imax < 2.9 V.
  • AC / DC, Relay output:
    • Contact type: Change-over, potential-free.
    • Max voltage (U~max): 253 V (AC)
    • Max current (I~max): 4 A (AC)
    • Max power (P~max): 1000 VA (cos ϕ = 1), 500 VA (cos ϕ > 0.7).
    • Current/Voltage ratings: 4 A for U ≤ 30 V; 0.2 A for U ≤ 253 V.
• Signal on Alarm:
  • DC, PNP transistor output: < 100 μA
  • AC / DC, Relay output: Relay de-energized.
• Switching Delay (free or covered):
  • FTC260: 0.5 s
  • FTC262: 0.8 s
• Overvoltage Category: Category II (as per EN 61010-1).
• Protection Class: Class I (as per EN 61010-1).

Power Supply

• DC, PNP transistor output:
  • Supply Voltage (U~): 10.8 to 45 V DC (transient pulses up to 55 V).
  • Current Consumption (max): 30 mA.
  • Reverse polarity protected.
• AC / DC, Relay output:
  • Supply Voltage (U~): 20 to 253 V AC or 20 to 55 V DC.
  • Current Consumption (max): 130 mA.

Electrical Connection

Requires connection to an earthed silo with metal or reinforced concrete walls. For non-conductive silos, an external earth wire must be connected to a conductive, earthed component. Potential matching leads may be required for dust explosion hazardous areas.

• Terminal Compartment:
  • Stranded wires: max 1.5 mm² (16 AWG) in end sleeves.
  • Electric wire: max 2.5 mm² (14 AWG).

Performance Characteristics

• Reference Operating Conditions: Ambient temperature 23 °C, medium temperature 23 °C, medium pressure 0 bar, dielectric constant εr = 2.6, conductivity < 1 μS, sensitivity setting 'C'.
• Hysteresis:
  • FTC260: 4 mm (0.16 in) horizontal, 7 mm (0.28 in) vertical.
  • FTC262: 5 mm (0.2 in) vertical.
• Switch Point:
  • FTC260: Probe center –5 mm (-0.2 in) horizontal; 40 mm (1.57 in) above probe tip vertical.
  • FTC262: 35 mm (1.38 in) above probe tip vertical.
• Probe Length Tolerances:
  • Up to 1000 mm (39.4 in): +0/–10 mm (+0/–0.39 in).
  • Up to 3000 mm (118 in): +0/–20 mm (+0/–0.79 in).
  • Up to 6000 mm (236 in): +0/–30 mm (+0/–1.18 in).
• Power Up Response:
  • FTC260: Max. 1.5 s.
  • FTC262: Max. 2 s.
• Long-term Drift:
  • FTC260: 3 mm (0.12 in) horizontal, 6 mm (0.24 in) vertical.
  • FTC262: 6 mm (0.24 in) vertical.
• Influence of Medium Temperature: Varies depending on the material being measured.

Installation

• Silo Material: Can be used in silos made of various materials.
• Mounting Point: Consider material mound angles and outlet funnel. Material flow should not be directed at the probe.
• FTC260 Specifics:
  • Minimum distance between probe tips: 200 mm (7.87 in).
  • Tip should point slightly downwards.
  • Maximum lateral load on probe rod must be considered for minimum detection. Suitable for loose, free-flowing materials.
• FTC262 Specifics:
  • Avoid installation in the center of the outlet cone.
  • Ensure sufficient distance from silo wall and buildup.
  • Note tensile strain on the probe rope and silo roof strength, especially for minimum detection. Suitable only for light, easily flowing solids that do not tend to form buildup.

Environment

• Ambient Temperature (Ta): –40 to +70 °C (–40 to +158 °F). For Dust-Ex version: –40 to +60 °C (–40 to +140 °F).
• Storage Temperature: –40 to +80 °C (–40 to +176 °F).
• Climate Class: As per EN 60068 part 2-38 (Z/AD), (IEC 68-2-38).
• Degree of Protection:
  • IP66; Type 4 enclosure (with F14 housing).
  • IP66; Type 4x enclosure (with F34 housing).
• Impact Resistance: Probe with F34 housing: 7 J.
• Vibrational Resistance: EN 60068-2-64 (IEC 68-2-64).
• Electromagnetic Compatibility:
  • Interference Emission: EN 61326, Electrical Equipment Class A.
  • Interference Immunity: EN 61326, Annex A (Industrial) and NAMUR Recommendation NE 21.
• Operating Height: Up to 2000 m (6600 ft) above mean sea level.

Process

• Process Temperature (Tp):
  • FTC260: –40 to +120 °C (–40 to +248 °F). Derating above 80 °C (176 °F). For Dust-Ex version: –40 to +80 °C (–40 to +176 °F).
  • FTC262: –40 to +80 °C (–40 to +176 °F).
• Process Pressure Range (pp):
  • FTC260: –1 to +25 bar (-14.5 to +362 psi).
  • FTC262: –1 to +6 bar (-14.5 to +87 psi).

Mechanical Construction

• Housing Types:
  • F14: Polyester PBT-FR housing, IP66.
  • F34: Aluminum housing, IP66.
• Material for Wetted Parts:
  • Probe FTC260/FTC262: PPS GF40.
  • Probe Rope FTC262: PE-HD.
  • Probe Rope Seal FTC262: VMQ.
• Process Connections:
  • FTC260: R 1, ISO 7/1 (BSPT) or 1 NPT. Adapters available.
  • FTC262: R 1½, ISO 7/1 (BSPT) or 1½ NPT.
• Housing Cable Entry: M20 coupling; NPT 1/2 or G 1/2 thread options for both F14 and F34 housings.
• Tensile Strength (FTC262): Max 3000 N up to 40 °C (104 °F); Max 2800 N at 80 °C (176 °F).

Operability

• Display Elements:
  • Green LED: Stand-by.
  • Red LED: Switch status.
• Operating Elements: Switches on the electronic insert allow selection of fail-safe mode (MIN/MAX) and sensitivity adjustment.

Certificates and Approvals

• CE Mark: Conforms to relevant EU directives.
• Ex Approval: ATEX (in conjunction with F34 aluminum housing). FM and CSA approvals in preparation.
• RCM-Tick Marking: Meets ACMA requirements for network integrity, performance, health, and safety, including EMC.

Supplementary Documentation

• Operating Manuals (BA): FTC260 (KA00093F/00/A6), FTC262 (KA00155F/00/A6), Rope Shortening for FTC262 (KA00157F/00/A6).
• Safety Instructions (XA): ATEX for FTC260 (XA00011F/00/A3), ATEX for FTC262 (XA00092F/00/A3).

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