Moore 62VA Constant Diff. Relay with Rotometer, New Surplus

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Moore 62VA Constant Diff. Relay with Rotometer, Qty 2

Qty 2: Moore 62VA Constant Differential Relay with Rotometer (B/M 12431-8/11WI).

Purge Rate: 0.09 to 2.1 SCFH, Built-in needle valve has internal
bypass to prevent tight shut-off of purge flow.

Flow Indicator: Indicating Rotometer 0.25 to 2.5 SCFH scale range

The Series 62 Constant-Differential Relays serve as air-flow controllers maintaining a constant air purge for each setting of an integral needle valve.

By maintaining a constant-differential pressure drop across a built-in needle valve (for any flow setting up to 2.1 cu. ft. of air per hour), Series 62 Relays ensure a constant volumetric rate of flow, regardless of variations in process or supply pressure.

The constant-differential pressure across the built-in needle valve is regulated by a spring-loaded diaphragm. This diaphragm controls the action of the supply-port plunger, which automatically admits supply air to the needle valve at the required rate. Excess purge air bleeds to the atmosphere.

Siemens constant-differential relays eliminate most of the problems encountered in conventional bubbling systems, because:
 Each relay holds the bubbling rate constant, thereby maintaining high measurement accuracy
 The differential pressure maintained across the needle valve is approximately 1-1/2 psi, which allows wider needle valve openings that are less subject to clogging.
 Full supply pressure (up to 150 psig) is connected to the purge system for a greater margin of safety.
 Ordinary air-line impurities have no effect

In addition to the preceding advantages, the Series 62
Constant-Differential Relays ensure reasonable purge rates at
all times, because they eliminate the need for a supply
regulator. Another safety feature is the automatic exhaust, which
bleeds off any excess air caused by the presence of foreign
particles on the pilot seat of the supply-port plunger.