User Manual

ManualsBrandsGems ManualsLevel SensorsLevel Switch NC / NO 20VA 250 VAC

P/N 72947

Rev. Y

Electrical Data

Standard reed switches in GEMS level switch units are hermeti-

cally-sealed, magnetically actuated, make-and-break type.

Switches are SPST or SPDT and are rated in Volt-Amps (VA).

See the chart below for maximum load characteristics of GEMS

level switches. CAUTION: Contact protection is required for tran-

sient or high in-rush current. Refer to GEMS Bulletin #133702 or

call your GEMS representative.

Single-Station Level Switches

Instruction Bulletin No. 72947

* Plastics ** Alloys

***

Specialty Switches: Please use caution when handling these units,

as shock may damage the thermostat temperature setting.

Thermostat units not CE approved.

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.

* Not U.L. Recognized ** Limited to 50,000 operations

Amps DC

.13

N.A.

.10

.13

.06

0.5

N.A.

Amps AC

.08

N.A.

.17

.08

0.5

.8**

Volts

0-50

120

100

0-30

120

240

0-50

120

240

120

240

General Use

Pilot Duty

General Use

100*

LS-1700**

LS-1700TFE*

LS-1750**

LS-1755**

LS-1800**

LS-1850**

LS-1900**

LS-1900TFE*

LS-1950**

LS-19735*

LS-30*

LS-38760**

LS-74780*

LS-77700**

TH 800-A***

Level Temp

1/8" NPT

1/8” NPT

1/8" NPT

1/2" NPT

1/4" NPT

1/8" NPT

3/8" - 16 Str. Thd.

1/8" NPT

1/8” NPT

1/4" NPT

1/4” NPT

1/8" NPT

3/8" - 24 Str. Thd.

1/2"

1/2”

1/2"

3/4" Wrench Flat

5/8"

21/32"

5/8"

1/2"

1/2”

5/8"

9/16" Wrench Flat

5/8”

1/2"

3/4"

(Slosh Shield Version

1-13/32”)

1-1/8”

1-1/2"

(Slosh Shield Version

1-13/16”)

1-1/32"

1-1/4"

3-1/2"

1-7/8"

2-1/8"

2-1/16"

1-1/2"

1-1/4"

(Slosh Shield Version)

1-7/8" (P/N 76707)

3/4” (P/N 201540)

1-7/8"

1-1/2”

1-1/2"

Series Mounting HEX Size

Float

Diameter

1/2"

1/4" NPT

5/8"

1-1/4"

1/8" NPT

LS-3*

Typical Wiring Diagrams

(Circuit Condition Dry)

SPST, With Thermostat Option

SPDT

SPST, Normally Open or Closed

Red

Black

Green

Red

Black

COM

N.C.

N.O.

Orange,

Yellow

White

Thermostat switches open or close

when ambient temperature reaches

specified setpoint. Thermostat units

not CE approved.

European Pressure Directive Addendum

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 Equip-

ment Directive, Article 1, Paragraph 2.1.3. The presence of a CE Mark on the unit does not relate to the Pressure Equipment

Directive.

Important Points!

Product must be maintained and installed in strict accordance

with the National Electrical Code and GEMS product catalog 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 combus-

tible atmospheres, disconnect power before servicing.

Pressure and temperature limitations shown on indi-

vidual catalog pages and drawings for the specified level

switches must not be exceeded. These pressures and tem-

peratures 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; particu-

larly wetted materials.

Life expectancy of switch contacts varies with applica-

tions. 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 tempera-

ture.

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 liq-

uid/vapor sealing if located in an enclosed tank.

Level switches must not be field repaired.

Physical damaged sustained by the product may render it un-

serviceable.

Summary of content (2 pages)

PAGE 1
Typical Wiring Diagrams (Circuit Condition Dry) Electrical Data Standard reed switches in GEMS level switch units are hermetically-sealed, magnetically actuated, make-and-break type. Switches are SPST or SPDT and are rated in Volt-Amps (VA). See the chart below for maximum load characteristics of GEMS level switches. CAUTION: Contact protection is required for transient or high in-rush current. Refer to GEMS Bulletin #133702 or call your GEMS representative.
PAGE 2
Installation A standard NPT female boss in tank top, bottom or side is all that is required. Units operate in any attitude - from the vertical to a 30° inclination - with lead wires up or down. Standard IPS pipe extends units to any intermediate level in the tank. (Figure 1) Moisture Protection: When moisture exists in conduit and extension pipes, the potential for this moisture to "wick" down the wire leads and into the switch assembly exists.