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5.1 DESCRIPTION
When programmed as a clock the BA364D will
display local time in twelve or in twenty four hour
format. Hours and minutes, or hours, minutes
and seconds may be displayed. The displayed
time is adjusted via the instruments internal
push-buttons which may be protected by a user
definable four digit security code to prevent
unauthorised or accidental adjustment.
The clock may be synchronised to an external
time standard via the instrument’s reset
terminals. When these two terminals are
connected together by an external switch contact,
the clock display will be reset to a
preprogrammed time. When the contacts open
the clock will continue running from the
preprogrammed time.
When fitted with the optional control outputs the
clock can be programmed to turn each solid state
output on and off twice during each twenty four
hour period.
5.1.1 Initialisation and loss of power
When power is applied to a BA364D clock,
following initialisation, the instrument will display
a flashing ‘A 12:00’ or ‘00:00’ depending upon
whether a twelve or twenty four hour display has
been selected. Seconds will also be shown if
selected. The clock will not start until a display
time has been entered, or the remote reset
contacts are closed and opened to synchronise
the clock display.
If during normal operation the power supply is
interrupted for more than 30ms, the display will
return to the flashing condition following
initialisation.
5.1.2 Controls
The BA364D clock is controlled and calibrated
via four front panel push-button switches. In the
display mode i.e. when the instrument is
displaying time the switch functions are:
Down
While these buttons are pushed the
+P
instrument will display the firmware
and version numbers plus the
programmed function.
.
Note
: When optional control outputs are fitted,
the BA364D clock may be programmed to
provide direct access to the setpoints from the
display mode when the
P + Up
push-buttons are
operated. – see section 5.5.10
5.1.3 Displays
The BA364D clock has a single digital display
and annunciators.
Time
Shows time in selected format
display
Reset
Activated while instrument is
Annunciator
being synchronised.
Control output
Activated when optional switch
Annunciators
output is closed
5.2 SYSTEM CERTIFICATES
In addition to the ATEX EC-Type Examination
Certificate, ITS have issued two system
certificates. One defines how the BA364D may
be used with Zener barriers and the other with
galvanic isolators.
Interface Certificate No
Zener barriers
Ex01E2007
Galvanic isolators
Ex01E2008
This section interprets these system certificates
and illustrates how to design clock systems with
Zener barriers and galvanic isolators.
System certificates are Certificates of Conformity
which are primarily issued for guidance in the UK.
They do not form part of certification to the
European ATEX Directive.
