BEKA BA334D, Manual

Page: 6 / 43

6
3.4 Remote reset terminals
The BA334D total display may be reset to zero
by connecting the reset terminals 7 and 8
together for more than one second. These two
terminals have the following input and output
safety parameters:
Uo = 3.8V dc
Io = 1.6mA dc
Po = 2.0mW
Ui = 28V dc
Ii = 100mA dc
Pi = 0.7W
The maximum equivalent capacitance and
inductance between them is:
Ci = 1nF
Li = 0
µ
H
The total display may be reset to zero from
within the hazardous area by any mechanically
operated switch connected directly to terminals
7 and 8.
To reset the total display from the safe area a
Zener barrier or intrinsically safe relay is
required to transfer the contact closure into the
hazardous area. Almost any intrinsically safe
relay with certification permitting the contacts
to be connected to equipment in the hazardous
area may be used. A positive diode return
Zener barrier may also be used as shown in
Fig 2. The system certificates list suitable
devices and define the maximum cable
parameters.
Note: The BA334D may be programmed so
that the total display can be reset to zero when
the Up and Down push-buttons are operated
simultaneously for more than two seconds.
See 6.12
3.5 Zones, gas groups and T rating
The BA334D has been issued with an EC Type
Examination certificate confirming that it
complies with the requirements for Group II
Category 1 G EEx ia IIC T5 (Tamb –40 to
60
o
C) specified in the ATEX Directive. When
connected to a suitable system the BA334D
may be installed in:
Zone 0 explosive gas air mixture
continuously present.
Zone 1 explosive gas air mixture
likely to occur in normal
operation.
Zone 2 explosive gas air mixture
not likely to occur, and if it
does will only exist for a
short time.
Be used with gases in groups:
Group A propane
Group B ethylene
Group C hydrogen
Having a temperature classification of:
T1 450oC
T2 300oC
T3 200oC
T4 135oC
T5 100oC
At an ambient temperature between –40 and
+60
o
C.
Note : the guaranteed operating temperature
range is –20 to +60
o
C
This allows the BA334D to be installed in all
Zones and to be used with most common
industrial gases.
3.6 Certification Label Information
The certification label is fitted in a recess on
the top outer surface of the enclosure. It
shows the ATEX certification information plus
BEKA associates name and location. Non
European certification information may also be
included. The serial number and date of
manufacture are recorded on a separate label
inside the terminal compartment.