Anti-corrosion explosion-proof flow switch NK33EX

The NK33EX series thermal conductivity flow switch is based on the thermal principle and contains two resistors inside a closed probe. One is heated as a detection resistor and the other is not heated as a reference resistor. When the medium flows, the heat on the heating resistor is taken away, and the resistance value is changed.

The difference between the two resistors is used as the basis for judging the flow rate. The probe adopts an anti scaling coating, which can effectively prevent the adhesion of scale, rust and other dirt in the pipeline, with stronger anti fouling ability and more stable operation.

Product Application

Gas liquid dual-use type; Widely used in industries such as petrochemicals, electricity, metallurgy, steel mills, papermaking, food processing, water treatment, battery factories, etc; And pneumatic and hydraulic systems can be used for monitoring the flow of circulating water, cutting fluid, and lubricating oil, as well as for pump idle protection.

Product Features

The K33EX series thermal conductivity flow switch can monitor the liquid flow in pipelines in real time, with no moving parts, no maintenance, and easy installation. One model is used for multiple pipe diameter requirements, providing switch output and using 6 LEDs to display the fluid flow rate status in real time, achieving the following monitoring functions:

Medium flow, reduce/increase flow rate; Existence/non existence of medium; Medium flow/static; Monitor the fluid flow velocity inside the pipeline, monitor flow interruption, or prevent pump idling.

Unique conical probe design can effectively prevent entanglement of objects in the medium. Fully waterproof shell design, unique waterproof adjustment knob, can be adjusted freely without disassembling the sealing screw, convenient and more reliable.
Suitable for a wide range of pipe diameters, adjustable set points, optional anti-corrosion type, with a maximum pressure resistance of 100Bar, indicator light directly displaying flow rate, optional relay, analog output or analog switch integrated output.

Technical Specifications

• Setting range: 1-150cm/s (water) 3-300cm/s (oil)
• 20-2000cm/s (air)
• Signal output: PNP, NPN, relay
• 1) Normally open+normally closed (SPDT)
• Power supply: 24V ± 20% DC
• Power on: Maximum 400mA (PNP or NPN type)
• Maximum 3A 24VAC/DC (relay type)
• No load current: maximum 80mA
• Flow indicator: LED row (6 pieces)
• Setting method: Potentiometer setting
• Pressure resistance range: 100bar (maximum customizable 40MPa)
• Medium temperature change: ≤ 4 ℃/s
• Response time: 1-13s, typical value of 2s
• Initialization time: approximately 8 seconds
• Electrical protection: reverse phase, short circuit, overload protection
• Explosion proof grade: ExdII CT6
• Protection level: IP67
• Medium temperature: -20 ° C to 100 ° C (customizable to -60 ° C to 150 ° C)
• Environmental temperature: -20 ° C to 80 ° C
• Storage temperature: -20 ° C to 100 ° C
• Wiring method: Terminal wiring M20 * 1.5
• Material: Probe: Stainless steel (customizable 316L/titanium alloy/polytetrafluoroethylene material)
• Shell: Cast aluminum
• Repetition accuracy: ± 2%

Wiring Diagram

Dimensional Drawing (mm)