EDS13-9F Datasheet, PDF (1/6 Pages) Fuji Electric – ZENER BARRIER

DATA SHEET
ZENER BARRIER
The ZENER BARRIER is a safety barrier for operating
an electronic instrumentation system as an intrinsically safe
explosion-proof system in processes subjected to explosive
gases or vapor. Various types are available for transmitter,
electro-pneumatic final controlling element, thermocouple
and resistance bulb, and can be combined with the field in-
strument mounted in a hazardous area to operate the measur-
ing instrument as an intrinsically safe explosion proof system.
PWZ
FEATURES
1. High safety explosion-proof zener barrier
• This barrier has been designed according to the latest ex-
plosion-proofing principles and it complies with the in-
spection standards of the Research Institute of Industrial
Safety, Ministry of Labor, of the Japanese Government.
IEC recommendations and VDE standards have been
taken into due consideration in design and manufacture.
• The voltage limiter circuit (zener diode) and thick film fuse
are fully incorporated, and the voltage limiter circuit is trip-
licated. Thus, safety and reliability of the system have
been improved by far.
• The thick film fuse offers a high safety maintenance rating
of 550V AC.
• The hybrid IC circuit forms a small and compact system,
and meets the creeping distance and other standard val-
ues. The system can be easily mounted on the instru-
ment panel. Cable connections and separation of both in-
trinsically safe and non-intrinsically safe circuits is as-
sured.
• In order to prevent handling error, various failproof devices.
(such as bright blue indication of intrinsically safe termi-
nals, use of contact prevention cover, doubling of bus bar
mounting screws, asymmetric design, color identification
according to models, etc.) are incorporated.
• The classification of hazardous areas (division 0) and group-
ing of explosive gases (i3nG5) are wider than with other
explosion-proof structures.
2. High reliability barrier
• The structure and circuits are simple with fewer parts than
an insulation barrier or repeater amplifier barrier, and fea-
ture high reliability.
• Since all processes from product development to manufac-
turing are performed by intracompany techniques and fa-
cilities, system quality is fully guaranteed with adoption of
reliable design techniques such as FMECA, etc., complete
manufacturing and testing facilities, manufacturing quality
control system, etc.
• The manufacturing techniques, manufacturing test facili-
ties, and quality control system for thick film fuse and hy-
brid IC have been inspected and approved by the Industrial
Safety Institute of the Japanese Government.
• The system also assures high reliability with the use of
strictly selected parts high derating design, reduced sol-
dering due to use of a hybrid IC, deterioration resistance
by thick film fuse, improved vibration resistance, etc.
3. Improved system design
• Since the safety maintenance rating is as high as 550VAC,
receiving instruments can be optionally selected and the
system easily can be connected to a computer control sys-
tem.
• Various types of barrier assemblies are prepared and easily
selected according to the measuring instruments com-
bined.
• Since this system uses a small-sized relaying terminal
board structure, the instrument panel can be easily de-
signed and connected.
EDS13-9f
Date Oct. 20, 1989