Flow Instrumentation > Switches > Dwyer V4 Series


Dwyer V4 Series Flotect Vane-Operated Flow Switch

Dwyer's V4 series vane-operated flow switch protects equipment and pipeline systems against damage from reduction or loss of flow. It can be used for fluids, gases, and flowing solids in pipe sizes 1-1/2" and larger.

The V4 uses a free-swinging vane that attracts a magnet within the solid metal switch body, actuating a snap switch by means of a simple level arm with no bellows, springs, or seals to fail. It installs directly into pipeline with a threadolet, tee, or flange, and the electrical assembly can be easily replaced without removing the unit from installation.

Key Specifications

  • Pipe sizes 1-1/2" and larger
  • Leak proof body machined from bar stock
  • Field adjustable
  • 1000 psig (brass) and 2000 psig (316 stainless steel) pressure ratings
  • Weatherproof, NEMA 4, explosion-proof enclosure
  • FM, UL, CSA, CE, ATEX, IECEx approvals

Specifications, Manuals, and Supporting Literature

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Model Selection Guide

Use this table to find the right model for your application.  Don't see the option you need? Call a Lesman sales specialist at 800-953-7626

Switch Body Brass Body Stainless Body
Catalog Number Catalog Number
SPDT V4-2-U V4-SS-2-U
DPDT V4-2-D-U V4-SS-2-D-U
ATEX Approved Construction -AT


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