Flow Switches - GEMS SENSORS & CONTROLS - (Version JPG) - Page n° 2 - PDF Catalogue | Technical Documentation

Gems._

FS-925 Series - General Purpose

Flow Rate Settings: Liquids: 0.1 GPM to 1.5 GPM

Air/Gases: See Flow Settings at right

FS-926 Series - Low Flow

Port Size: 1/4" NPT

Primary Construction Material: Brass or Stainless Steel Setting Type: Fixed

Flow Rate Settings: Liquids: 50-300 cc/min.

Air/Gases: See Flow Settings at right

FS-925/926 Series

U.L. Recognized — File No. E31926 CSA Listed — File No. LR30200 FM Approved — File No. 1H3A2.AX and 0A8A3AE

These two series of precision-calibrated switches provides reliable and consistent performance; repeatability is within 1%. FS-925 and FS-926 units are factory preset for actuation at specified flow rates.

These switches provide accurate detection of excessive or insufficient flow rates in such applications as: protecting against loss of fluid flow in hydraulic systems, assuring proper coolant flow in semiconductor processing equipment, monitoring high pressure lubrication systems, and ensuring proper air flow in water/waste systems.

Specifications


	Wetted Materials
	Housing	Brass or 316 Stainless Steel
	Piston
	In Brass Housing	Polysulfone for water; Brass for oil or air
	Stainless Steel Housing	316 Stainless Steel
	Low Flow Piston (FS-926)	Same as Housing
	Spring	316 Stainless Steel
	O-Ring	Viton®
	Other Wetted Parts	Epoxy
	Pressure Rating
	Operating, Maximum	1000 PSIG (69 bar)
	_Proof	2500 PSIG (172 bar)
	Burst	5000 PSIG (345 bar)
	Operating Temperature
	With Brass or S.S. Piston	-20°F to +300°F (-29°C to +148.9°C)
	With Polysulfone Piston	-20°F to +225°F (-29°C to +107.2°C)
	Repeatability	1% Maximum Deviation
	Set Point Accuracy	4-1 fl⁰/
	Set Point Differential	15% Maximum
	Switch*	SPDT, 20 VA
	Inlet/Outlet Ports	1/4" NPT
	Electrical Termination	No. 18 AWG, 24" L., Polymeric Lead Wires

Both the FS-925 and FS-926 use a spring-loaded piston to detect positive flow with great precision. They act upon direct fluid flow and will not show "false-positive" flow indication as can happen with sensors using indirect sensing methods such as pressure measurement. The FS-926 incorporates an additional lap-fitted piston for very low flows; see below.

Dimensions

W (6.3 mm)

4-1/8' (104.7 mm)

9/32' DIA. (7.1 mm) MTG. HOLES (2)

I 2-3/8' i (60.3 mm)

1/2' (12.7 mm)

1-1/4' (31.7 mm)

*See "Electrical Data" on Page X-5 for more information.

27/32' (21.4 mm)

1/4" NPT

both ports

Double Piston Detects Minute Flow - FS-926

An additional, lap-fitted piston is used in Gems FS-926 Series to accurately detect low-flow rates. Calibration is determined by one or more metering holes in the end of the low-flow piston, which regulate bypass flow, and therefore the actuation setting.


	i_	-1
	1' (25.4 mm)	m
		T (44.4 mm)

3/4'

(19.0 mm)

BY-PASS HOLES

MAGNET CARRIER PISTON

Electrical Connection, 1/2" NPT C

METERING ORIFICE

When metered bypass flow is exceeded, the resultant pressure differential displaces the low-flow piston, moving the magnet carrier piston to actuate the reed switch. Two large bypass holes in the piston skirt are exposed after actuation to maintain low pressure drop.

1/2" (12.7 mm)

i-10

Flow Switches - GEMS SENSORS & CONTROLS - #2

Intrinsically safe level sensor, Tank level gauge, Moisture monitor, Diaphragm pressure switch, Level controller