Dwyer Mark Series Valve Position Indicator

The Dwyer Mark Series position indicators include three models: Mark 1, Mark 3, and Mark 4. All standard models have visual position indicators and are weatherproof, explosion-proof, and submersible. Each indicator has the option to hold up to six switch outputs. The Mark Series offers 14 different versions of switch outputs such as: inductive sensors, high temperature sensors, hermetically sealed switches and more.

Mark 1 & Mark 3 feature a magnetic coupling that isolates the switch compartment, completely sealing the unit from the surrounding atmosphere for maximum hazard and leak protection. Both models are ideal for corrosive environments. Mark 3 can also be used for multi-turn applications with one to 25 revolutions.

Mark 4 has a thru-shaft design that features a 1" bearing for long life and o-rings to seal the switch compartment for hazard, corrosion, and leak protection. It is a lower cost alternative to the Mark 1 Series for less demanding applications.

Key Specifications

  • Mark 1 & Mark 4: EZset cams on switch models for simple set point adjustment
  • Multiple switches and transmitter options
  • Coated aluminum or cast 316 stainless steel enclosure
  • Visual indicator comes standard on units that display Open/Close status

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.

A complete catalog number looks like this: 12AD0

Description Catalog Number
Construction Mark 1, Magnetic Coupling
Mark 4, Thru-Shaft
1_ _ _ _
4_ _ _ _
Output Type 2 Switches _2_ _ _
Switch Type
and Rating

SPDT Snap, Rated: 15A @ 125/250/480 VAC;
1/8 h/p @ 125 VAC, 1/4 hp @ 250 VAC,
1/2 A @ 125 VDC, 1/4 A @ 250 VDC
_ _A_ _

Driving Method Direct Drive (or Yoke) with Visual Indicator _ _ _D_
Enclosure Black Painted Aluminum _ _ _ _0


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