Omega Products SBG111954 User Manual

SELECTION GUIDE FOR OMEGA®ZENER



APPROVED

BARRIERS FOR INTRINSIC SAFETY

OMEGA®Solid State Relays and Zener Barriers for Intrinsic Safety

The maximum energy possible at the switch terminals of the OMEGA zener barriers is far below the explosive point of the most volatile surrounding gas conditions. The type of non-voltage-producing switch or sensor best fitted for the application can be used, since the entire switching circuit is rendered intrinsically safe by the OMEGA®zener barrier. Because the switching circuit is low voltage, there is no shock hazard to operating or maintenance personnel.

Installation and Maintenance

OMEGA®zener barrier units are normally installed in a safe area and connected to the sensor in a hazardous location; no explosion-proof or protective housings are needed. Units install singly in any position, or can be grouped on a common earthgrounded plate with mounting tabs to provide electrical grounding. Between 6 and 32 threaded electrical terminals are conveniently placed atop the unit housings.

Single- and dualchannel zenner barriers, shown smaller than actual size.

OMEGA®zener barriers must be installed in conformance with the National Electrical Code and the Instruction, Installation and Service Bulletin supplied with all units. Periodic checks of ground bonding and cleanliness of units and terminals constitute the only maintenance required.

Approvals Hazardous Locations

Group Model No. UL FM CSA Class Division ABCD EFG

SBG111950 XXX I,II 1,2 XXXX XXX

Single Channel SBG111956 XXX I,II 1,2 XXXX XXX Zener Barriers

Dual Channel Zener Barriers

Note: Zener barrier model numbers SBG54803 and SBG54806 are certified by CSA for mounting inside a suitable enclosure in Div. 2 or non-hazardous locations and must be connected by means of the 2 studs provided to a grounded copper busbar or equivalent.

SBG111954 XXX I,II 1,2 XXXX XXX

SBG113000 XXX I,II 1,2 XXXXX SBG114166 XXX I,II 1,2 XXXX XXX SBG54803 XXX I,II 1,2 XXXX SBG54806 XXX I,II 1,2 X

K-105

POWER SUPPLY ANNUNC.

(+)

(–)

(+)

(–)

FUSE

3 4

5 6

HAZARDOUS AREA SAFE AREA

SENSOR

SIGNAL

CONDITIONER

ZENER BARRIER

EARTH GROUND (2 PLACES)

ZENER BARRIER UNITS

EARTH GROUNDED MOUNTING PLATE

INTRINSICALLY SAFE WIRING

RESISTANCE TO GND. MUST BE LESS THAN 1 FROM MOUNTING SCREW OR BRACKET TO EARTHING MEMBER TO ENSURE INTEGRITY

NON-INTRINSICALLY SAFE WIRING

INTRODUCTION TO SOLID STATE SINGLE-

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APPROVED

AND DUAL-CHANNEL ZENER BARRIERS

FOR INTRINSIC SAFETY

OMEGA®SingleChannel and DualChannel Zener Barriers Feature Intrinsic Safety With Solid State Reliability—And These Additional Advantages:

⻬ Installation

Economy

⻬ No Explosion-

Proof Enclosures of any Kind Needed for Sensor Wiring

⻬ Compact Size—

Streamlines Multiple Installations

⻬ Encapsulated

Construction— Impervious to Dust and Moisture, Shock and Vibration Resistant

Single- and DualChannel Barriers

For most non-voltage-producing devices located in a hazardous area, a single zener barrier that is negative-earth-grounded (see figure

1) can be used for intrinsic safety. Instrumentation that produces an output (signal conditioners) usually

SBG54803 dual-channel zener barrier, $315, shown smaller than actual size.

SBG111950 single-channel zener barrier, $132, shown smaller than actual size.

requires two barriers,

one for each “floating” lead. Here, a dual-channel barrier can be provided (see figure 2), or for applications in which the instrument signal return level cannot be reduced, a supply barrier and a low resistance return barrier can be supplied (see diagram 2B on page K-110).

Sensor switch may be any non-voltage-producing device. Flow and level switches, temperature switches (thermostats), pressure switches, or passive, resistive transducers or transmitters are typical.

Fig. 1 Positive single-channel zener barrier with

Fig. 2 Positive dual-channel zener barrier with

Note: Terminals 3, 4, 5, and 6 are common and

Installation and Maintenance

OMEGA®Zener barriers are installed in non-hazardous (safe) locations, and may be grouped on a common, earth-grounded mounting plate. Intrinsically safe sensor wiring must be separated from non-intrinsically-safe input wiring in separate conduits or raceways to prevent by-pass during testing or servicing. Routine inspections every two years or less to check integrity of earth-grounding and electrical connections, and to make sure the unit is clean, constitute the only maintenance normally required.

Installation and maintenance must be in accordance with the National Electrical Code and the applicable OMEGA operator’s manual.Ω

negative ground.

floating leads.

are bonded to the mounting tabs for positive redundant grounding.

Figure 1

Figure 2

K-106

SINGLE-CHANNEL ZENER BARRIERS, DC

81 (3-3/16)

36.5

(1-7/16)

12.3

(31/64)

Mounting Accessories

Model No. Price Description

SBG113530 $20 TS32 style rail

mounting clip

SBG111950 single-channel zener barrier, $132, shown smaller than actual size.

Output terminal cover

Mounting screw

Red polysulfone housing

Locating Pin

Protective cover over the output terminal (3).

SBG113530 optional rail mounting clip, $20.

Single-channel zener barriers can be supplied with a clip for rail mounting. Clip attaches to barrier with mounting screw supplied.

Dimensions: mm (in)

Omega Products SBG111954 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual