Omega Engineering SBG41705, SBG25873, SBG22445, SBG25872 instruction sheet Description, Unpacking

SBG22445, SBG25872, SBG25873 (Non-Latching), SBG41705 (Latching) Solid-State Relays

for Intrinsic Safety Use Instruction Sheet M1773/0794

DESCRIPTION

The OMEGA® SBG22445, SBG25872, SBG25873 and SBG41705 Solid- State Relays are used as "intrinsically safe switching circuits in hazardous locations, with non-voltage- producing sensors. When installed in accor- dance with this manual, these field sensors are suitable for Class I, Division 1, 2, Groups A, B, C and D, and Class II, Division 2, Groups E, F and G as defined by Article 500 of the National Electric Code.

UNPACKING

Remove the Packing List and verify that you have received all equipment. If you have any questions about the shipment, please call the OMEGA Customer Service Department at 1-800-622-2378 or (203) 359-1660. When you receive the shipment, inspect the container and equipment for any signs of damage. Note any evidence of rough handling in transit. Immediately report any damage to the shipping agent.

NOTE

The carrier will not honor any claims unless all shipping material is saved for their examination. After examining and removing contents, save packaging material and carton in the event reshipment is necessary.

Important: Read carefully and completely before installing or connecting the solid-state relays.

ASSOCIATED EQUIPMENT

Caution: The intrinsically safe relays can be installed in panel assem- blies in Class I, Div.2, Groups A, B, C and D or in a non-hazardous location. Only the sensor's terminals provide an intrinsically safe switch circuit (Fig. 1, 2). (Exia) means associated equipment "Appareilage connexe", located in safe area.

MOUNTING AND ENCLOSURE CONSIDERATION

• Field wiring of intrinsically safe circuits is to be segregated from

non-intrinsically safe wiring by use of suitable barriers, separate

wireways or trays (see Fig. 3).

• Intrinsically safe and non-intrinsically safe connection points should

be located sufficiently apart to prevent any possibility of bypassing

or miswiring during installation or servicing of equipment.

• The enclosure shall contain a cautionary statement as follows:

"CAUTION: ANY SUBSTITUTION OF COMPONENTS MAY

IMPAIR INTRINSIC SAFETY".

• The mounting plate must be grounded to ensure intrinsic safety.

Resistance between the plate and earth ground should be less than

Fuse F1

InputLoad

VAC

Fuse

F1(EXIA)

Non-Hazardous

Location

Hazardous Location

Sensor Switch

Note: For 120V application, only one fuse is required in the ungrounded circuit of the input line.

Fig. 1. Connection Diagram

(All Models Except SBG41705)

VACLOAD

AC Load

Latching Solid-State

Relay SBG41705

On C Off Non-Hazardous

Location

Sensor Switch Hazardous Location

Fig. 2. Connection Diagram: Model SBG41705

one ohm. (See Figs. 4 and 5 for recommended selection of

grounding hardware and refer to Article 250 of the National Electrical Code for methods and practice.)

INSTALLATION OF SENSOR SWITCH AND ASSOCIATED FIELD WIRING

•The nature of the sensor switch must be that it is a non-voltage-

producing, essentially resistive termination or other device specifically examined and approved for use with the intrinsically safe solid-state relay.

•The conductors of the intrinsically safe circuit should be sealed in a rigid metal conduit at the point where the wiring enters the hazardous area. The wiring and sensor switch should be such that conductive dusts in the hazardous area will not close the circuit.

•Hazardous area field wiring will store energy due to distributed capacitance and inductance in proportion to its length. It is

therefore recommended that the characteristics of the cable be known and judged against the length of

run and atmosphere of exposure. TheWARNING Product must be maintained

following chart is presented as a guideline and installed in strict accor- in determining the limits of reactance for dance with the National Elec-

Earth

Ground

(2 Places)

Common

Earth-

Grounded

Mounting

Plate

Intrinsically

Safe Wiring

To Sensors

Non-Intrinsically

Safe Wiring

Multiple

Units

Resistance to ground must be from bracket to earthing member to insure integrity of system. (Must be below one ohm.)

signal loops in the hazardous area wiring trical Code. Failure to observe for the intrinsically safe solid-state relays. this warning could result in

serious injuries or damages.

Note: All intrinsically safe wiring must be segregated from non-intrinsically safe wiring.

GROUP	CAPACITANCE	INDUCTANCE
A & B	0.1 µF	3 mH
C	0.2 µF	10mH
D	0.3 µF	20mH

Example: Typical values of capacitance for a twisted pair of copper wires is between 20 and 60 pF per foot. Using the maximum value of 60pF/ft, Groups A & B could have a run of 1500+ feet with safety. Inductance

Fig. 3. Multiple units grouped on a common, earth-grounded mounting plate.

Intrinsically Safe

Solid-State Relays

#10 Screw

#10 Lockwasher*

of a typical twisted pair is between 0.10 and 0.20 µH/ ft, thus making a cable run in this example essentially

Mounting

#10 Lockwasher*

determined by the capacitance.

•Whenever possible, the actual measured parameters should be used in making the determination of allowable length.

•Shielded cable is not required, but if used in the application, the

shield must be returned to ground, the same point at mounting tab.

Plate#10

Nut

*(Lockwashers to be internal or external tooth type)

Fig. 4. Unit Mounting Detail