BEKA BA368C, Руководство пользователя

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1.2.4 Clock
When programmed as a digital clock the BA368C
will display local time within a hazardous area.
The two optional solid state control outputs may be
programmed to turn on and off twice during each
24 hour period.
See section 5 of this manual for a detailed
description of the clock functions.
1.3 INITIALISATION
Each time power is applied to the BA368C
initialisation is performed. After a short delay the
following display sequence occurs:
All segments of the display are activated for
about 2 seconds.
The product firmware and version number
are shown on the top display and the current
instrument function i.e. Countr, ELAPSE,
tACHO or CLOC are displayed on the lower
display for 2 seconds.
The BA368C starts to function using the
calibration information stored in the
permanent memory.
1.4 INTRINSIC SAFETY CERTIFICATION
1.4.1 ATEX certification
The BA368C has been issued with EC-Type
Examination Certificate number ITS01ATEX2004
by Notified Body Intertek Testing Services (ITS)
confirming compliance with the European ATEX
Directive 94/9/EC for Group II, Category 1, gas
atmospheres, EEx ia IIC T5. The instrument bears
the Community Mark and subject to local codes of
practice, may be installed in any of the European
Economic Area (EEA) member countries. i.e.
Austria, Belgium, Denmark, Finland, France,
Germany, Greece, Ireland, Italy, Luxembourg, The
Netherlands, Norway, Portugal, Spain, Sweden
and the United Kingdom. ATEX certificates are
also accepted in Iceland, Liechtenstein,
Switzerland and the Czech Republic.
This manual describes installations which conform
with BS EN60079:Part14 Electrical Installation in
Hazardous Areas. When designing systems for
installation outside the UK, the local Code of
Practice should be consulted.
1.4.2 Power supply
When installed in a hazardous area the BA368C
must be powered via a Zener barrier or galvanic
isolator from a dc supply located in the safe area.
The input safety parameter for terminals 1 and 2
are:
Ui = 28V dc
Ii = 100mA dc
Pi = 0.7W
Any certified Zener barrier or galvanic isolator with
output safety parameters within these limits may
be used. Two system certificates provide
guidance to help selection of suitable devices. The
maximum equivalent capacitance and inductance
between terminals 1 and 2 is:
Ci = 20nF
Li = 20
µ
H
When installing a system not covered by the
BA368C system certificates, these figures must be
subtracted from the maximum cable parameters
for the certified device powering the BA368C.
1.4.3 Pulse input terminals
The BA368C has two identical inputs designated A
(terminals 3 & 4), and B (terminals 5 & 6). Each
may be connected to a switch, open collector or
certified intrinsically safe 2-wire proximity detector.
The safety parameters of each input are:
Ui = 28V dc
Ii = 100mA dc
Pi = 0.7W
Uo = 10.5V dc
Io = 9.2mA dc
Po = 24mW
Note: when programmed as a tachometer only
one input may be used and when programmed as
a clock neither of the inputs are available.
Hazardous area mechanically operated switches
comply with the requirements for
simple apparatus
and may be directly connected to either input.
Similarly, optically isolated open collector outputs
that comply with the requirements for
simple
apparatus may also be directly connected to either
input.
The BA368C system certificates specify some of
the intrinsically safe 2-wire proximity detectors that
may be connected directly to the two instrument
inputs. Other certified intrinsically safe detectors
may be used providing that the input safety
parameters of the detector are less than the
BA368C output parameters.