Disc RF Admittance Level Switch for Blocked Chute Detection

The Disc RF Admittance Level Switch (DRFA) is a sturdy and rugged point-level switch that is used to identify blocked chute conditions in various material handling plants, quarries, and mining operations to avoid corresponding spills, ensuring seamless process operation.

Disc RF Admittance Level Switch for Blocked Chute Detection

The Disc RF Admittance Level Switch comprises two components:

1. a disc-shaped sensor and
2. a control unit.

The sensor is installed on the chute and linked to the controller. As the quantity of material in front of the sensor rises, it results in increased capacitance, which activates an output relay.

This level switch is perfect for a range of applications, including crushed rock and sand in mining operations, coal in thermal and steel plants, lime and dolomite in quarries, and sugar and grains in silos and agricultural machinery.

Specifications of Disc RF Admittance Level Switch

Probe

• Enclosure x Conduit Connection: Cast Al. Powder Ctd. WP IP65 x PG13.5 Cable Gland, Cast Al. Powder Ctd. Exd Gr. IIB x ½” NPT DC Cable Gland, SS304 WP. IP65 x PG 13.5 Cable Gland
• Sensing Element: SS304
• Insulation: UHMWPE or PTFE
• Pr. Conn./ Shield Material: CS, SS304 or SS316
• Process Connection Type: 4” NB ASME 150# Flange
• Max. Temperature: 70°C (UHMWPE), 200 °C (PTFE)

Control Unit (Remote)

• Enclosure x Conduit Connection: Cast Al. Powder Ctd. WP IP65 x PG13.5 Cable Gland, SS304 WP IP65 x PG 13.5 Cable Gland,
• Supply: 230 VAC or 110 VAC or 24 VDC ±10%
• Output: 1 DPDT Relay Contact, 5A, 250 VAC (Resistive)
• Power Consumption: 2 VA
• LED Indication: Green-Normal; Red-Alarm; Yellow- Power On (inside the enclosure)
• Safety Operation: Fail Safe High or Low (Field Selectable)
• Switching Delay (Optional): Adjustable from 2 to 20 sec probe-free or probe covered
• Ambient Temperature: 0 to 60 °C
• Signal Cable: Low capacitance, co-axial 3 core PVC cable x 5 meters long

Disc RF Admittance Level Switch Features

Salient features of the RF Admittance Level Switch with a probe include:

• The probe is flush-mounted to the chute wall, so there is nothing protruding to interfere with or obstruct material flow.
• There are no moving parts, resulting in minimal maintenance requirements.
• The switch utilizes a three-element coat guard technique to ignore any build-up or coating or dust conditions leading to false signals.
• The switch has a fail-safe design, providing added reliability in operation.
• The insulation material is erosion-resistant UHMWPE.
• The switch offers the option of an adjustable switching delay.

Installation of Disc RF Admittance Level Switch

A typical installation schematic is shown in the below image. A sensor and controller were installed near the tank where we have to detect the blocked materials.