SLA..M / B Admittance Level Switch

Sapcon’s SLA..M/B Admittance Level Switch utilizes specially designed Immuno Coat Probe. It offers a reliable solution to level detection problems which have been so far difficult to solve with Capacitance-type systems that used conventional probes.

Applications of SLA..M/B Admittance Level Switch

The sensor specializes in level limit detection of fine, coarse, solids of low dielectric constant that otherwise have a tendency to stick, coat and develop static charge at high vessel temperatures. The sensor is also ideal for applications dealing with bulk material handling.

SLA..M/B is commonly used in applications that use media such as powders, sand, sugar, pulverized coal, food grains, cement, stones, fly­ash, bed­ash, clinkers, great cooler, sticky and hygroscopic materials like slag, dust, etc.

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The probe comprises of sense, shield and ground electrodes electrically isolated from the metallic tank by means of suitable insulators. The sense electrodes and the vessel wall serve as the two electrodes of an imperfect capacitor with the service material as the dielectric. A change in material level causes a change in admittance of this imperfect tank capacitors.

  • Power Consumption: Less than 05 VA
  • Power Supply:  18 -55 V DC, 90-260 V AC
  • Self-diagnosis
  • Suitable for very dusty environment
  • High temperature durability (Up to 1000°C)
  • Immune to application material coating on the probe
Mechanical Specifications

 Probe Length

  • Rod Probes:
    • 200mm – up to 3000mm
  • Rope Probes:
    • Extend up to 600mm to 12000mm


  • P5: IP-65 Weatherproof Housing
  • FA: Flameproof for Gas Group IIA and IIB

Process Connection (Mounting Arrangement)

  • Threaded Mounting: 1, 1-1/2”, 2” BSP/NPT
  • Flanged Mounting: As per specification
  • Tri-Clover: As per specification
  • SMS union coupling type


  • PTFE
  • Ceramic
  • Others

Wetted Parts and Mounting Material

  • S4: SS – 304
  • S6: SS – 316
  • SL: SS – 316L

Process Temperature

  • A (Ambient): below 80°C
  • H1 (High temperature): up to 150°C
  • H2 (High temperature): up to 250°C
  • H3 (High temperature): up to 600°C
  • H4 (High temperature): up to 1000°C with cooling fins
Electrical Specifications


  • SLA series with electronics insert ICA 3000
    • Sticky media e.g. slurries, wet sand
    • Split electronics, sensor – controller distance maximum 1km
  • SLA..M with Dot Display
    • Low dielectric media e.g. cement, fly ash, clinkers, ESP hoppers
    • Remote electronics with 15m distance between probe and controller
  • SLA..B with Bar Display
    • Remote Electronics with maximum distance of 50m from the probe
    • Low dielectric media e.g. cement, fly ash, clinkers, ESP hoppers


  • Integral type (Electronics integral with probe)
  • Remote type (Electronic separated by a special cable)

Input power supply & Outputs

  • SLA 122/ 120M / 120B: Single SPDT with (90-260 V AC) / 24 V DC
  • SLA 222 / 220M / 220B: Double SPDT with (90-260 V AC) / 24 V DC
  • SLA 322 / 320M / 320B: Single SPDT & Time Delay with (90-260 V AC) / 24 V DC
  • SLA 622 / 620M / 620B: Double SPDT & Time Delay with (90-260 V AC) / 24 V DC
  • SLA 822: Double SPDT, Time Delay & two channels with (90-260 V AC) / 24 V DC
  • SLA 922: Three SPDT, Time Delay & three channels with (90-260 V AC) / 24 V DC

Power Consumption

  •  Maximum 5 W

Fail-safe Setting

  • Field selectable (through toggle switch)
  • Open: Fail-safe High, Close: Fail-safe Low

Response Time

  • 0.5 – 2 Sec

Time Delay Settings

  • Cover and Uncover Delay: 0.5s to 60s, through potentiometer

Sensitivity Setting

  • Field Selectable (through toggle switches)


  • 100 KHz and 500 KHz
Applications Specifications

Application Material

For all Industries requiring level limit detection in Bulk Material Handling

  • Powders, sand, sugar, Pulverized coal, Food grains
  • Cement, Stones, Fly-ash, Bed-ash, Clinkers
  • Granular material
  • Sticky and hygroscopic materials like honey, paste, cream, syrup, etc.
  • Flameproof Housing IIa / IIb certified by CMRI, Dhanbad
  • CE certification
  • IP 65 from ETDC Indore
  • ISI mark from the Bureau of Indian Standards
Switching Indication
  • 2 LED’s / Dot / Bar type display
  • Red: Alarm, Yellow: Sensing, Green: Normal