Description
The QSKN is a mechanical screw-in paddle flow switch with wetted parts and terminal enclosure in stainless steel. It is particularly suited to liquids and gases in fire protection, chemicals, industrial automation, machinery, smelting and hydraulic lubrication.
A spring-loaded paddle (baffle) stands across the pipe; the flow deflects it and a linkage operates a microswitch. Setting range across the product 20 … 1800 L/min, set by the pipe bore and the paddle fitted. Five paddles (31 … 132 mm long) are supplied. Repeatability ± 2.5 % of the total range; an accuracy is not documented; hysteresis 8 … 80 L/min by bore and paddle. Output microswitch, SPDT, switching capacity 250 V AC, 3 A. Connection via screw terminals and one cable entry.
Body, process connection, connecting rod and paddle in stainless steel, terminal enclosure in stainless steel, weight 0.55 kg. Process connection R1 taper thread for pipes of DN25 and above. Pressure rating 16 bar per parameter table, pressure loss 0.08 bar at maximum flow, medium temperature up to 250 °C, ambient -25 … +80 °C. A declaration of conformity is not documented in the datasheet. Before sizing, note: As explosion protection the datasheet names only “EX CT4”, without type of protection, gas group or certificate, and T4 does not match 250 °C, so explosion protection is not substantiated. The pressure is 100 bar in the data block and 16 bar in the parameter table. No protection grade is given.
Advantages at a glance
- Wetted parts and enclosure in stainless steel
- Mechanical principle, mechanical and electrical parts separated
- Five paddles supplied
- Setting range 20 … 1800 L/min by bore and paddle
- Repeatability ± 2.5 % of the total range
- SPDT contact 250 V AC, 3 A
- Low pressure loss 0.08 bar