Chemtrol Product - Liquid Flow Switch
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Liquid Flow Switch

Liquid Flow Switches series

Flow control of water and aggressive media (depending on model).
Alarm signal of flow shortage. Available in brass for normal media, and in stainless steel AISI316L for aggressive media.


Applications suitable:

Well-suited in pipes of general industrial plants:

  • heating and air conditioning systems
  • refrigeration systems
  • heat pumps

Technical Data

Contacts: Dust-tight microswitch with switching contacts SPDT
Switch capacity: 15 (8) A, 24…250 Vac
Working: -40…+85 °C / 10…90% r.h. (without condensing) Max liquid
Temperature: -40…+120 °C
Max pressure: 11 bar (SF2: 30 bar)
Flow rate: see flow rate schedule 1-2-3
Connection: standard R1“ (DIN 2999) for series SF1 and SF2
Body: see schedule above
Paddles: stainless steel AISI 316L
Housing: Base in ABS, transparent PC cover
Storage: -40…+85 °C / < 95% r.h.
Protection: IP65, class I
Size: 140 x 62 x 65 mm
Weight: 950 g


The flowswitch can be installed in every position far from elbows or throttlings, with arrow on flow direction. If pipe is vertical, recalibrate range to balance paddle weight.

If the device is downwards mounted take care to slags, and apply it in a straight pipe far from filters, valves, etc with length at least 5 times the diameter of pipe upstream and downstream the unit.