Dwyer GVS User Manual

Maintenance . . .

Occasional cleaning when excessive contamination is present in the
liquid is the only maintenance normally required. With system shut­down and no liquid in piping, remove bonnet nut to disassemble unit for
cleaning. It is not necessary to remove unit body from the system.
Remove retainer ring “A” for complete shuttle disassembly. Remove
ring “B” to disassemble disc only.

Disc

Bonnet

Nut

Shuttle

Assembly

Retainer Ring "A"

Retainer
Ring "B"

Globe Valve Flow Switches

Series GVS/G9

Installation

Install GVS or G9 Series units in piping system using standard pipe fitting procedures. Be careful to keep sealing
compound out of the unit. Be sure to observe direction of flow - marked “IN” and “OUT” on housing. See chart below
for port and wrench hex. sizes.

MAINTENANCE/REPAIR

Regular maintenance of the total system is recommended to assure sustained optimum performance. These devices are
not field repairable and should be returned to the factory if recalibration or other service is required. After first obtaining a
Returned Goods Authorization (RGA) number , send the unit freight prepaid to the following. Please include a clear descrip­tion of the problem plus any application information available.

Dwyer Instruments, Inc.
Attn: Repair Department
102 Highway 212
Michigan City , IN 46360

Important Points!

Product must be maintained and installed in strict accordance
with the National Electrical Code and Dwyer product catalog
and instruction bulletin. Failure to observe this warning could
result in serious injuries or damages.

For hazardous area applications involving such things as (but
not limited to) ignitable mixtures, combustible dust and
flammable materials, use an appropriate explosion-proof
enclosure or intrinsically safe interface device.

The pressure and temperature limitations shown on the
individual catalog pages and drawings for the specified flow
switches must not be exceeded. These pressures and
temperatures take into consideration possible system surge
pressures/temperatures and their frequencies.

Selection of materials for compatibility with the media is critical
to the life and operation of Dwyer products. Take care in the
proper selection of materials of construction, particularly wetted
materials.

Life expectancy of switch contacts varies with applications.
Contact Dwyer if life cycle testing is required.

Ambient temperature changes do affect switch set points,
since the specific gravity of a liquid can vary with temperature.

Dwyer Products have been designed to resist shock and
vibration; however, shock and vibration should be minimized.

Filter liquid media containing particulate and/or debris to
ensure the proper operation of our products.

Electrical entries and mounting points in an enclosed tank
may require liquid/vapor sealing.

Dwyer Products must not be field-repaired.
Physical damage sustained by the product may render it

unserviceable.

GVS Adjustable units are installed horizontally, in line, with lead wires up. G9 Adjustable units are installed vertically;
lead wires up, as shown. 150 micron filtration is suggested for use with all units.

Note: Bonnet and shuttle assembly should be removed from unit during welding or brazing.
(See bonnet assembly removal under “Maintenance” on back of sheet.)

Flow Setting Adjustment . . .

Adjustment Screw with Slot in Min.
Flow Position.

Standard units are normally supplied with adjustment set
at “minimum flow” - adjustment screw slot (and vane
within unit) in vertical position, as shown below. Adjust­ment may be made with unit on test stand or installed in
system. With liquid flowing at desired rate, adjust screw
in side of housing until unit just actuates. (Switch closes
or opens, as desired.)

Flow

Switch

Electrical Connection . . .

Lead wires and 1/2" NPT or junction box with 1/2" NPT.

Electrical Data

Typical Wiring Diagram . . .

Switch Ratings - Maximum Resistive Load

VA

20

Volts

0 - 30

120
240

Amps AC

.4
.17
.08

Amps DC

.3
.13
.06

DWYER INSTRUMENTS,INC.

P .O.BOX 373 MICHIGAN CITY, INDIANA 46361, U.S.A.

Phone: [phone] www.dwyer-inst.com
Fax: [phone] e-mail: [e-mail]
Lit-By Fax: [phone]

Specifications (GVS Series)

Specifications (G9 Series)

Wetted Materials
Housing
Shuttle
Bonnet
Spring
Other Wetted Parts

Bronze
Teflon
Bronze or Stainless Steel
316 Stainless Steel
Viton, Ceramic

Pressure Rating
Operating
Proof
Operating Temperature
Repeatability
Set Point Accuracy
Set Point Differential
Switch

*

Inlet/Outlet Ports
Electrical Termination

400 PSIG @ 100°F (37.8°C)
800 PSIG @ 100°F (37.8°C)

-20°F to +200°F (-29°C to +93.3°C)
1% Maximum Deviation
±10%
15% Maximum
SPDT, 20 VA
1" NPT
No. 18 AWG, 24" L.,

Polymeric Lead Wires

*See "Electrical Data" on front page

Wetted Materials
Housing



Shuttle
Spring
O-Ring
Other Wetted Parts

Bronze



Delrin
316 Stainless Steel



Viton

Ceramic
Pressure Rating, Max.
Operating
Proof
Operating Temperature
Repeatability
Set Point Accuracy
Set Point Differential
Switch

*

Inlet/Outlet Ports
Electrical Termination

400 PSI @ 100°F (+37.8°C)

800 PSI @ 100°F (+37.8°C)

-20°F to +180°F (-29°C to +82.2°C)

1% Maximum Deviation

±10%

15% Maximum

SPDT, 20 VA

3/4" NPT

No. 18 AWG, 24" L.,

Polymeric Lead Wires

*See "Electrical Data" on front page

#18 AWG, 24" L.

Polymeric

Jacket

▲

3"

▼

▼

Dimensions (GVS Series)

1/2" NPT

Bonnet

Switch

Housing

3 1/4"

▼

▼

Inlet Port

1" NPT Port

▼

▼

1 25/32"

▼

3-27/32"

Dimensions (G9 Series)

1-7/16"

HEX

1-3/8"

1/2" NPT

1-3/8"