Murphy VS2, VS2C, VS2EX, VS2EXRB, VS2EXR Installation Instructions Manual

Shock/Vibration Control Switches
Installation Instructions

Models: VS2, VS2C, VS2EX, VS2EXR, VS2EXRB and VS94

GENERAL INFORMATION

Please read the following instructions before installing. A visual inspection of this product for damage during shipping is recommended before
mounting. It is your responsibility to have a qualified person install the unit, and make sure installation conforms with NEC and local codes.

Model VS2EX

LISTED

*

BEFORE BEGINNING INSTALLATION OF THIS MURPHY PRODUCT

✔✔

Disconnect all electrical power to the machine.

✔✔

Make sure the machine cannot operate during installation.

✔✔

Follow all safety warnings of the machine manufacturer.

✔✔

Read and follow all installation instructions.

VS-7037N

Revised 04-05

Section 20

(00-02-0185)

R

VS-7037N page 1 of 8

Description

The Murphy shock and vibration switches are available in a variety of
models for applications on machinery or equipment where excessive
vibration or shock can damage the equipment or otherwise poses a
threat to safe operation. A set of contacts is held in a latched position
through a mechanical latch and magnet mechanism. As the level of
vibration or shock increases an inertia mass exerts force against the
latch arm and forces it away from the magnetic latch causing the latch
arm to operate the contacts. Sensitivity is obtained by adjusting the
amount of the air gap between the magnet and the latch arm plate.

Applications include all types of rotating or reciprocating machinery
such as cooling fans, engines, pumps, compressors, pump jacks, etc.

Models

VS2: Base mount; non hazardous locations.
VS2C: C-clamp mount; non hazardous locations.
VS2EX: Explosion-proof; Class I, Div. 1,

Groups C and D.

VS2EXR: Explosion-proof with remote reset.
VS2EXRB: Explosion-proof; Class I, Div. 1, Group B; with

remote reset.

VS94: Base mount; non hazardous locations, NEMA 4X/IP66.

Remote Reset Feature (VS2EXR,
VS2EXRB and VS94 only)

Includes built-in electric solenoid which allows reset of tripped unit from a
remote location. Standard on VS2EXR and VS2EXRB. Optional on
VS94 (options listed below).

-R15: Remote reset for 115 VAC

-R24: Remote reset for 24 VDC

Time Delay Option (VS94 only)

Overrides trip operation on start-up. For VS94 series models, the delay
time is field-adjustable from 5 seconds up to 6-1/2 minutes with a 20­turn potentiometer (15 seconds per turn approximately). Options listed
below:

-T15: Time delay for 115 VAC

-T24: Time delay for 24 VDC

Space Heater Options (VS94 only)

This optional space heater board prevents moisture from condensing
inside the VS94 Series case. Options listed below:

-H15: Space heater for 115 VAC

-H24: Space heater for 24 VDC

Warranty

A limited warranty on materials and workmanship is given with this FW
Murphy product. A copy of the warranty may be viewed or printed by going
to www.fwmurphy.com/support/warranty.htm

WARNING

VS-7037N page 2 of 8

DIMENSIONS

3 in.

(76 mm)

4-3/4 in.

(121 mm)

2-1/4 in.
(57 mm)

5-1/8 in.

(130 mm)

Mounting Holes

Slotted
Sensitivity
Adjustment

Reset
Push
Button

4-19/32 in.

(116 mm)

Plug

1/4 x 1/2 in.

(6 mm x 13 mm)

Slot 2 places

3 in.

(76 mm)



4-3/4 in.

(121 mm)



Slotted
Sensitivity
Adjustment

5-7/16 in.
(138 mm)



Reset
Push
Button

Weatherproof
Strain Relief
Bushing

C-Clamp

27/32 in.
(21 mm)



1/2 NPT 

Conduit

5-5/8 in.

(143 mm)

3 in.

(76 mm)

Mounting Holes

Reset
Push
Button

Slotted
Sensitivity
Adjustment

5-1/4 in.

(133 mm)

Mounting Holes

4-7/8 in.

(124 mm)

6-3/8 in.

(162 mm)

3/8 in.
(10 mm)
4 places

1-3/4 in.
(44 mm)

10-5/8 in.

(270 mm)



6 in.

(152 mm)



4-1/2 in.

(114 mm)

Mounting Centers

1/2 NPT

Conduit

9-1/8 in.

(232 mm)

Mounting Centers



10-3/16 in.

(259 mm)



8-5/8 in.

(219 mm)



2-1/2 in.
(64 mm)



VS2

VS2C

VS2EX and VS2EXR

VS2EXRB

7-9/64 in.
(181 mm)



4 in.

(102 mm)



6-1/2 in.

(165 mm)



6-29/32 in.

(176 mm)



Manual
Reset
Push-button

Mounting slot
5/16 x 9/16 in.
(8 x 14 mm)
4-places.

6-1/2 in.

(165 mm)



4-5/8 in.

(118 mm)



1-5/8 in.
(41 mm)



4 in.

(102 mm)



3/4 NPT
conduit fitting


VS94

VS-7037N page 3 of 8

SPECIFICATIONS

VS2 and VS2C

•

Case: Weatherproof (equal to NEMA 3R) suitable for non-hazardous areas.

VS2: Base mount
VS2C: C-clamp mount. Includes 45 feet (13.7 meters), 2-conductor 16

AWG, 30 strands/0.25 mm strand dia. (1.5 mm2) cable, and five cable
hold down clamps.

•

Contacts: SPDT double make leaf contacts, 5A @ 480 VAC.

•

Range adjustment: 0 - 7 G’s; 0 - 100 Hz /0.100 in. displacement.

VS2EX

•

Case: Explosion-proof and weatherproof aluminum alloy housing;

meets NEMA 7/IP50 specifications; Class I, Division 1, Groups C &
D; UL and CSA listed.*
VS2EX: base mount.

•

Snap-switches: 2-SPDT snap-switches; 5A @ 480 VAC;*

2A resistive, 1A inductive, up to 30 VDC.

•

Range adjustment: 0 - 7 G’s; 0 - 100 Hz /0.100 in. displacement.

•

Normal Operating Temperature: -40 to 140°F (-40 to 60°C).

VS2EXR

•

Case: Same as VS2EX.

•

Snap-switch: 1-SPDT snap-switch and reset coil; 5A @ 480 VAC;*2A

resistive, 1A inductive, up to 30 VDC.

•

Remote Reset (optional):

Option Operating Current

-R15: 350 mA @ 115 VAC

-R24: 350 mA @ 24 VDC

•

Range adjustment: 0 - 7 G’s; 0 - 100 Hz /0.100 in. displacement.

•

Normal Operating Temperature: -40 to 140°F (-40 to 60°C).

VS2EXRB

•

Case: Explosion-proof aluminum alloy housing; rated Class I,

Division 1, Group B hazardous areas.

•

Snap-switch: 1-SPDT snap-switch with reset coil (option available for

additional SPDT switch); 5A @ 480 VAC; 2A resistive, 1A inductive,
up to 30 VDC.

•

Remote Reset:

Option Operating Current

-R15: 350 mA @ 115 VAC

-R24: 350 mA @ 24 VDC

•

Range adjustment: 0 - 7 G’s; 0 - 100 Hz /0.100 in. displacement.

VS94

•

Case: Polyester fiberglass reinforced; NEMA type 4 and 4X; IP66; CSA

types 4 and 12.

•

Conduit Fitting: 3/4 NPT conduit fitting connection.

•

Normal Operating Ambient Temperature:

0 to 140°F (-18 to 60°C).

•

Snap-switches: 2-SPDT snap acting switches; 5A @ 480 VAC; 2A

resistive, 1A inductive, up to 30 VDC.

•

Range adjustment: 0 - 7 G’s; 0 - 100 Hz /0.100 in. displacement.

•

Heater (optional):

Option Operating Current

H15 .023 A @ 115 VAC
H24 .12 A @ 24 VDC

•

Remote Reset (optional):

Option Operating Current

R15 .17 A @ 115 VAC
R24 .36 A @ 24 VDC

•

Time Delay (optional):

Option Operating Current Standby Current

T15 .360 A @ 115 VAC .01 A @ 115 VAC
T24 1.15 A @ 24 VDC .01 A @ 24 VDC

•

Time Delay/Remote Reset: Adjustable 20-turn potentiometer from

5 seconds to 6-1/2 minutes (15 seconds per turn approximately).

*CSA and UL listed with 480 VAC rating.

The VS2 and VS94 series shock switches are sensitive to shock and
vibration in all three planes of motion - up/down, front/back and side/side.
Front/back is the most sensitive (The reset pushbutton is located on the
“front” of the unit). For maximum sensitivity mount the unit so that the
front faces into the direction of rotation of the machine. (See Dimensions on
page 2 for sensitivity adjustment location).

The VS2 and VS94 Series must be firmly attached/mounted to the machine
so that all mounting surfaces are in rigid contact with the mounting surface
of the machine. For best results, mount the instrument in-line with the
direction of rotating shafts and/or near bearings. In other words, the reset
push button should be mounted pointing into the direction of shaft rotation
(see page 5). It may be necessary to provide a mounting plate or bracket to
attach the VS2 and VS94 Series to the machine. The mounting bracket
should be thick enough to prevent induced acceleration/vibration upon the
VS2 or VS94 Series. Typically 1/2 in. (13mm) thick plate is sufficient. See
illustrations on page 5 for typical mounting locations.

CAUTION:

A dust boot is provided on the reset pushbutton
for all series to prevent moisture or dust intrusion. The sensitivity
adjustment for model VS2EX is not sealed; therefore, mounting

orientation should be on a horizontal plane or with the sensitivity adjustment
pointing down. Sensitivity adjustment for model VS2 is covered by a plug.
The plug must be in place and tight to prevent moisture or dust intrusion.

C-Clamp Installation (VS2C model only)

A C-Clamp is supplied with the VS2C model only.
The C-Clamp is shipped installed on the VS2C
but must be installed on the VS2EX and
VS2EXR switches.

1. The C-Clamp (B) will already be installed on

a 1/4 in. (6 mm) thick steel mounting plate
(A). Bolt the VS2 switch to the mounting
plate as illustrated — with four 5/16 in.
bolts, nuts, and washers.

2. The mounting location should provide

convenient access to the TATTLETALE

®

push button (C).

3. The hardened set screw and nuts (D) are used to

tighten the switch to an I-Beam or cross member such as a
Sampson post of an oilwell pumpjack.

WARNING: STOP THE MACHINE AND DISCONNECT ALL
ELECTRICAL POWER BEFORE BEGINNING INSTALLATION.

INSTALLATION

Continued on next page.

A

B

C

D