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Appendix 1
FM & cFM Approval for Installation in USA and
Canada
A1.0 Factory Mutual Approval
For installations in the USA and Canada both
indicators and all accessories have been approved
by Factory Mutual as intrinsically safe for Class I,
Divisions 1 and 2 and as nonincendive for Class I,
Division 2.
Installations must comply with the BEKA
associates control drawing CI320-22, ANSI/ISA
RP12.6 and the National Electrical Code
ANSI/NFPA70. Installations in Canada must
comply with Canadian Standard C22.2.
A1.1 4/20mA input in intrinsically safe circuit
The BA327C and BA328C have 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 BA327C and BA328C are also Factory Mutual
approved as nonincendive for Class I, Division 2
locations, which allows both indicators 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'.
A1.3 Accessories
The Factory Mutual approval includes the Alarms,
Lineariser, Tare function and Display backlight
accessories. Only the alarms and backlight have
external connections which affect installation.
A1.3.1 Alarms
The FM approval allows the BA327C and BA328C
to be fitted with an alarm card which contains two
totally independent alarms each with a single pole
solid state output.
A1.3.1.1 intrinsic safety
Each alarm has a galvanically isolated single pole
output which may be connected to any intrinsically
safe circuit having entity output parameters equal
to or less than:
Voc, Vt
= 32V
Isc, It
=
159mA
Each of the alarm outputs has a maximum
equivalent capacitance and inductance of:
Ci
=
0.04µF
Li
=
0.02mH
These figures must be subtracted from the
maximum permissible cable capacitance and
inductance allowed for the Zener barrier or
galvanic isolator connected to the alarm output.
See Figs 8, 9 and 10.
