Description
The QSKM is a mechanical screw-in paddle flow switch with body, process connection, connecting rod and paddle in stainless steel. It is particularly suited to liquids and gases in industrial automation, machinery, air compression, refrigeration and air conditioning in pipes of DN25 and above.
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.
All four wetted parts in stainless steel; no steel grade is named. 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. The data block (90 °C) and the rating plate (120 °C) give different temperatures. Bore, medium and switching value have to be given with the order; the order code has no field for them.
Advantages at a glance
- All wetted parts 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
- Optional IP67 protective case