Operation
The
SIEMENS
System 3 Intrinsically Safe Zone Model
ZS-30, consisting of a Zone Module and a Diode
Shunt Barrier, is designed for use in System 3 low
voltage control panels. With detection devices located
in hazardous areas identified as Class I, II, and III,
Division 1, Groups A, B, C, D, E, F, and G, the intrinsi-
cally safe characteristic is achieved by using a diode
shunt barrier (P/N 515-180238) with the ZS-30. The
Diode Shunt Barrier, though physically a separate unit
of ZS-30, must always be used to achieve an intrinsi-
cally safe zone. The Diode Shunt Barrier limits the
energy to the detector circuit.
The following equipment is covered by this instruction
sheet.
Item Name and
Model Number
Description
NON-HAZARDOUS LOCATION EQUIPMENT
Model ZS-30
Zone module (P/N 515-022079)
Model 515-180238
Diode shunt safety barrier
(P/N 515-180238)
HAZARDOUS LOCATION EQUIPMENT
Detector DI-3IS
Detector S121
Detector S122
Base DB-3
For use with DI-3IS
Cable 465-514391
Limited-energy shielded cable
(Optional)
Check that each device to be located in the intrinsi-
cally safe area has an FM intrinsically safe label. In
addition, direct shorting manual stations and/or
thermal detectors (devices not containing any energy
storing, or voltage producing, components) may be
connected in the detector loop without jeopardizing the
intrinsically safe characteristics of the system.
NEC Hazardous Location Classification
Class I:
Class I locations are those in which flammable
gases or vapors are (or may be) present in the air in
quantities sufficient to produce explosive or ignitable
mixtures.
Class II:
Class II locations are those that are hazardous
because of the presence of combustible dust.
Class Ill:
Class Ill locations are those that are hazardous
because of the presence of easily ignitable fibers or
flyings, but in which such fibers or flyings are not likely
to be in suspension in the air in quantities sufficient to
produce ignitable mixtures.
Division 1:
A Division 1 location is a location (a)
in
which hazardous concentrations of flammable gases or
vapors exist continuously, intermittently, or periodically
under normal operating conditions; or (b) hazardous
concentrations of such gases or vapors may exist
frequently because of repair or maintenance operations
or because of leakage; or (c) breakdown or faulty
operation of equipment or processes that might release
hazardous concentrations of flammable gases or vapors
occur and might also cause simultaneous failure of
electric equipment.
Group A:
Group A atmospheres contain acetylene.
Group B:
Group B atmospheres contain such chemi-
cals as butadiene, hydrogen ethylene oxide
(or gases or vapors of equivalent hazard to
hydrogen, such as manufactured gas), or
propylene oxide.
Group C:
Group C atmospheres contain such chemicals
as acetaldehyde, cyclopropane, diethyl
ether, ethylene, isoprene, or unsymmetrical
dimethyl hydrazine (UDMH).
Group D:
Group D atmospheres contain such chemicals
as acetone, acrylonitrile, alcohols, ammonia,
Operation and Installation Instructions
MODEL ZS-30
Intrinsically Safe Module
Fire Safety
Siemens Building Technologies, Inc.
8 Fernwood Road
Florham Park, New Jersey 07932
Siemens Building Technologies, Ltd.
2 Kenview Boulevard
Brampton, Ontario L6T 5E4 CN
P/N 315-024056-17
