14
Appendix 1
Installation in USA
A1.0 Factory Mutual Approval
For installations in the USA the BA304C and all
accessories have been approved by Factory
Mutual as intrinsically safe for Class I, II and III,
Divisions 1 and 2; and nonincendive for Class I, II
and III, Division 2.
Installations must comply with the BEKA
associates control drawing CI300-22, ANSI/ISA
RP12.6 and the National Electrical Code
ANSI/NFPA70. The supplied bonding plate must
be fitted between the two conduit / cable entries.
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 4/20mA input in intrinsically safe circuit
The BA304C has been evaluated under the entity
concept, and may be connected in series with any
intrinsically safe circuit having output parameters
equal to or less than:
Voc, Vt
=
32V
Isc, It
=
200mA
The 4/20mA input terminals have a maximum
equivalent capacitance and inductance of:
Ci
=
0.02µF
Li
=
0.01mH
These figures must be subtracted from the
maximum permissible cable capacitance and
inductance allowed for the Zener barrier or
galvanic isolator powering the loop into which the
indicator is installed.
See Figs 2 and 3.
A1.2 4/20mA input in nonincendive circuit
The BA304C is Factory Mutual approved as
nonincendive for Class I, II and III Division 2
locations, which allows it 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.
A1.3 Classes, Divisions, Gas Groups and
Temperature rating
The indicator has been approved by Factory
Mutual for installation in all Classes, Divisions and
Gas Groups as shown below.
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
Class II Group E
Group F
Group G
Class II Group E
Group F
Group G
Class III
Class III
A2.0 Backlight
Both the separately powered and the loop powered
backlight may be used.
A2.1 Separately powered backlight
The backlight is segregated from the measuring
circuit and has been approved as a separate
intrinsically safe circuit under the entity concept.
The backlight may be powered from any certified
associated apparatus such as a Zener barrier or
galvanic isolator having output parameters equal to
or less than:
Voc, Vt
=
32V
Isc, It
=
159mA
The backlight terminals have a maximum
equivalent capacitance and inductance of:
Ci
=
0.03µF
Li
=
0.01mH
These figures must be subtracted from the
maximum permissible cable capacitance and
inductance allowed for the Zener barrier or
galvanic isolator powering the backlight.
Segregation between the backlight and the
measuring circuits should be maintained by
following the wiring methods recommended in
ANSI/NFPA70 article 504.
See Fig 8