4
Fig 7 Single stage alarm using galvanic isolator
.
7.2 Multi-stage alarm
Fig 8 shows a typical application in which the first and second stage alarm
tones are activated by the alarm outputs of a BA327C intrinsically safe
loop powered indicator. The BA327C alarm outputs have been certified as
simple apparatus and may therefore be used to switch the BA385 sounder
in the hazardous area. The contacts of most certified intrinsically safe
relays may also be used in the same way.
Fig 8 Loop-powered BA327C intrinsically safe indicator
activating BA385 first and second stage alarms
8. CABLE PARAMETERS
The BA385 has zero total equivalent capacitance and inductance Ci and
Li. The maximum permitted cable parameters specified on the certificate
for the barrier or isolator connected to the sounder therefore apply.
normally these limits are not restrictive. Only the maximum permitted
capacitance in IIC applications is likely to limit practical cable length.
9. ACCESSORIES
9.1 Tag number
The BA385-IIB and BA385-IIC sounders can be supplied identified by a
tag number thermally printed on a self adhesive label.
10. Servicing
No attempt should be made to repair a faulty BA385-IIB or BA385-IIC
sounder. Suspect sounders should be returned to BEKA associates or
our local agent for repair.
11. Guarantee
Sounders which fail within the guarantee period should be returned to
BEKA associates or our local agent. It is helpful if a brief description of
the fault symptoms is provided.
12. Customer comments
BEKA associates are always pleased to receive comments from
customers about our products and services. All communications
are
acknowledged and whenever possible, suggestions are
implemented.
APPENDIX 1
Installation in USA
A1.0 Factory Mutual Approval
For installations in the USA the BA385-IIB and the BA385-IIC sounders
have been approved by Factory Mutual as intrinsically safe for Class I,
Divisions 1 and 2; and as nonincendive for Class I, Division 2.
BA385-IIB installations must comply with the BEKA associates control
drawing CI385-12 and BA385-IIC installations with control drawing CI385-
13. All installations must also comply with ANSI/ISA RP12.6 and the
National Electrical Code ANSI/NFPA70.
Copies of the FM control drawings are available from BEKA associates
and:
Exloc Corporation
PO Box 1100
Manassas
VA 20108
USA
Tel:
703 361 5364
Fax:
703 368 3221
e-mail: [email protected]
All the intrinsically safe circuits shown in this instruction manual may be
used for installations in the USA, providing the Zener barriers and galvanic
isolators comply with the specified Factory Mutual entity parameters.
A1.1 intrinsic Safety Approval
Both the BA385-IIB and the BA385-IIC sounders have been evaluated
under the entity concept. The sounders may be connected to any
intrinsically safe circuit having output parameters equal to or less than:
Voc, Vt
= 32V
Isc, It
=
110mA
Po
=
0.8W
The input terminals of both sounders have no equivalent capacitance and
inductance, i.e. Ci and Li are zero. The maximum permissible cable
capacitance and inductance allowed for the Zener barrier or galvanic
isolator powering the sounder may therefore be used subject to the
limitation defined on the control drawings.
A1.2 Nonincendive Approval
The BA385-IIB and the BA385-IIC are Factory Mutual approved as
nonincendive for Class I, Division 2 locations, which allows both sounders
to be installed in Division 2 without the need for Zener barriers or galvanic
isolators. The maximum supply voltage must be less than 32V, and the
wiring must be nonincendive or 'Division 2 suitable' as defined in the
National Electrical Code ANSI/NFPA70. For supply voltages above 16V,
a series resistor having a value of (Vsupply – 16) / 0.04 ohms is required.
A1.3 Classes, Divisions, Gas Groups and Temperature rating
The two models have been approved by Factory Mutual for installation in
the following Divisions and Gas Groups.
BA385-IIB sounder
Intrinsic Safety
Nonincendive
Division 1 or 2
Division 2
Class I Group C
Group D
Class I Group C
Group D
BA385-IIC sounder
Intrinsic Safety
Nonincendive
Division 1 or 2
Division 2
Class I Group A&B
Group C
Group D
Class I Group A&B
Group C
Group D
Both sounders have a T4 rating and may be used at ambient
temperatures between –20 and +60
o
C.
Note:
The BA385-IIB and BA385-IIC are not approved for use with Class
II and III dusts and fibers.
Issue 2 September 2002
