Gems Sensors & Controls LS-2050 Operating Manual

Maintenance . . .

An occasional cleaning when excessive contamination is present in the liquid is all that is
normally required. To clean unit: Compress split end of cam pivot pin, remove pin and
disassemble unit as shown below. Wipe parts clean with hydrocarbon solvent and
reassemble unit. Lock cam pivot pin by spreading split end slightly with screwdriver.

Housing and

Stem Assembly

Spring

Cam Pivot Pin

Permanent

Magnet

Shuttle

Float and Cam

Assembly

LS-2050/LS-52100 Series

Side-Mounted Level Switches

Instruction Bulletin No. 72950

Units are side-mounted in the tank at the point of high, low or intermediate
level sensing. Ideal for tanks with "hard-to-get-at" tops or bottoms. Float
and cam action is positive. Standard versions are U.L. Recognized - File
No. E45168. Explosion-proof units are approved for Class I, Division I,
Group D hazardous areas.

Electrical Connection . . .

Electrical connection is provided by wire leads with 1/2" NPT or junction box with 1/2"
NPT.

Typical Wiring Diagrams . . .

Important Points!

Product must be maintained and installed in strict accordance

with the National Electrical Code and GEMS technical brochure
and instruction bulletin. Failure to observe this warning could re­sult in serious injuries or damages.
An appropriate explosion-proof enclosure or intrinsically
safe interface device must be used for hazardous area appli­cations involving such things as (but not limited to) ignitable
mixtures, combustible dust and flammable materials.
*** Warning: To prevent ignition of flammable or combus­tible atmospheres, disconnect power before servicing.
Pressure and temperature limitations shown on individual
catalog pages and drawings for the specified level 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 GEMS level switches. Take
care in the proper selection of materials of construction; par­ticularly wetted materials.

P/N 72950

Rev. P

Life expectancy of switch contacts varies with applications.
Contact GEMS 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.
Level switches have been designed to resist shock
and vibration; however, shock and vibration should be
minimized.
Liquid media containing particulate and/or debris
should be filtered to ensure proper operation of GEMS
products.
Electrical entries and mounting points may require liq­uid/vapor sealing if located in an enclosed tank.
Level switches must not be field repaired.
Physical damage sustained by the product may ren­der it unserviceable.

Standard
Versions

Explosion-Proof Versions

FM Approved

CSA Listed

LS-2050's

30288
30290
48068
48069

----

55690

----

----

----

55690

----

----

LS-52100's

52100
116971
116972

*

See "Electrical Data" on next page for more information

121753

----

----

121753

----

----

**100 VA switches are not UL recognized or CSA listed

Specifications . . .

Stem & Mtg Material
Float Material

Other Wetted

Materials

Operating Temp °F

PSIG, Max. @ 70°F
Mounting Attitude

Switch Differential
(In Liquid)

Liquid Specific Gravity
Lead Wires

Brass

Buna N

316 SS,

Beryllium Copper,

Teflon,

Ceramic

Water: To +180°F

Oil: -40° to +250°F

1/2" Min.

.8 Min.

LS-2050 LS-52100

150

Horizontal: ±15°

#18 AWG, 24" L., Polymeric

Switch*

SPDT, 20 VA
SPDT, 20 VA

SPST, 100 VA, N.O.
SPST, 100 VA, N.C.**

SPDT, 20 VA

SPST, 100 VA, N.O.
SPST, 100 VA, N.C.**

316 SS
316 SS

316 SS
304 SS

SS,

Teflon,

Ceramic

Teflon,

Ceramic

-40°F to +300°F

900

500

Approx. 3/4"

.9 Min. .85 Min.

**

**

Dimensional Data . . .

LS-2050 Series
(Brass/Buna N

1/2" NPT

3-7/16"

(87.3 mm)

LS-2050 Series
(All Stainless Steel)

1"

NPT

LS-52100 Series

1"

NPT

5-9/32" Approx. (134.1 mm)

Approximate Actuation
Level - Contacts Transfer

1"

NPT

←→

7/8"

(22.2 mm)

1-3/8"

(34.8 mm)

Approximate Actuation Level ­Contacts Transfer on Ascending Level

←→

5-1/16"

(128.6 mm)

on Ascending Level

↓

1"

(25.4 mm)

↑

4-1/8"

Approx.

(104.8 mm)

Approximate Actuation Level ­Contacts Transfer on Ascending Level

5-1/16"

(128.6 mm)

↓

1"

(25.4 mm)

↑

↓

5/8"

↑

2-3/8" ±1/8"

(60.3 mm)

↓

3-5/8"

Approx.

(92.0 mm)

↑

↑

3-1/4"

Approx.

(82.5 mm)

↓

To Install LS-52100 Series or LS-2050
Series Units with Buna N Float . . .

Insert unit from the outside through 1" NPT boss in the

Float In

Actuating

Position

tank side and tighten so that the arrow on the unit housing
is pointing upward.
Important: Units should be installed in environments free
from excessive contamination and high shock.

Arrow Must

Point Upward

Float In

Dry Position

To Install LS-2050 Series Units with Stainless Steel Float . . .
(Use either Method A or Method B shown below)

Arm

Arm

Float

2" NPT

Boss

Inside

of Tank

Lockwasher

Float

Method A: From outside of tank. Unscrew
and remove float and lockwasher from unit
arm. Thread a 2" to 1" NPT reducer (by
others) onto unit and reassemble float and
lockwasher. Insert unit and reducer in 2"
NPT boss in tank side and tighten so that
arrow on unit housing points upward.

Method B: When inside of tank is
accessible. Unscrew and remove float

and lockwasher from unit arm. Insert unit in
1" NPT boss in tank and tighten so that
arrow on housing points upward. Reas­semble float and lockwasher on unit arm
from inside of tank.

2" to 1" NPT

Reducer

Arrow Must

Point Upward

Arrow

Must Point

Upward

Lockwasher

1" NPT

Boss

Electrical Data . . .

Switch Ratings - Max. Resistive Load

VA Amps DC

Volts

0-30

20

120
240

100*

This product is suitable for Class I and Class II applications only, per the requirements
of standard EN60730 and any additional specific requirements for a particular
application or medium being sensed. Class I compliance of metal bodied units requires
a ground connection between the metal body and the earthing system of the
installation. Class I compliance of plastic bodied units in contact with a conductive
medium requires that the medium be effectively earthed so as to provide an earthed
barrier between the unit and accessible areas. For Class III compliance, a supply
at safety extra-low voltage (SELV) must be provided. Please consult the Factory
for compliance information on specific part numbers.

The product is designed and manufactured in accordance with Sound Engineering Practice as
defined by the Pressure Equipment Directive 97/23/EC. This product must not be used as a
“safety accessory” as defined by the Pressure Equipment Directive, Article 1, Paragraph 2.1.3.
The presence of a CE Mark on the unit does not relate to the Pressure Equipment Directive.

120
240

Amps A.C.

.4
.17
.08

.8**

.4

European Pressure Directive

.3
.13
.06

N.A.
N.A.

* 100 VA switches are not U.L.

Recognized or CSA listed

**Limited to 50,000 operations.