Description
The QSKL is a mechanical screw-in paddle flow switch for pipes from DN25 to DN150. It is particularly suited to liquids and gases in industrial automation, machinery, air compression, refrigeration and air conditioning.
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, with a PG7 gland on the IP67 case.
Body and paddle in stainless steel, process connection and connecting rod in brass, seal NBR, outer housing ABS, weight 0.55 kg. Process connection R1 male. Pressure rating 16 bar, pressure loss 0.08 bar at maximum flow, medium temperature 90 °C, ambient -25 … +80 °C, protection IP33, IP67 with the optional case. A declaration of conformity is not documented in the datasheet. Before sizing, note: As supplied the switch is only IP33, and the IP67 case is needed for outdoor or washdown duty. Stainless steel and brass in the same wetted path form a galvanic cell in conductive water. The data block (90 °C) and the rating plate (120 °C) give different temperatures.
Advantages at a glance
- Mechanical principle, mechanical and electrical parts separated
- Five paddles supplied
- One device for pipes from DN25 to DN150
- Repeatability ± 2.5 % of the total range
- SPDT contact 250 V AC, 3 A
- Low pressure loss 0.08 bar
- Factory setting to the wanted switching value offered
- Optional IP67 protective case