BEKA BA368C, Руководство пользователя

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5.5.10 Adjusting control output setpoints
while displaying time
Direct access to the control output setpoints from
the clock display mode is obtained by operating
the
P and Up push-buttons simultaneously as
shown in Fig 5.4. If the setpoints are not protected
by a security code, the control output setpoint
prompt 'OP1: On1' will be displayed. If the
setpoints are protected by a security code, 'COde'
will be displayed first. Pressing
P again will enable
the control output security code to be entered digit
by digit using the
Up and Down buttons to change
the flashing digit and the P push-button to move
control to the next digit. If the correct code is
entered pressing
E will then cause alarm setpoint
prompt 'OP1: On1' to be displayed. If an incorrect
security code is entered, or a button is not pressed
within ten seconds, the instrument will
automatically return to the display mode.
Once within the menu pressing the Up or Down
buttons will scroll through all the setpoints. When
the required setpoint is displayed pressing
P will
reveal the existing setpoint time. This may be
adjusted using the
Up and Down push-buttons and
the P button to move control to the next digit.
When the required time has been entered,
pressing
E will return the display to the setpoint
identification from which another setpoint may be
selected, or the clock may be returned to the
display mode by pressing
E again.
Fig 5.4 Setpoint adjustment from the clock
display mode
Each of the two control outputs has two or four
setpoints depending upon whether the output has
been programmed to turn on & off once or twice in
each 24 hour period. – see 5.5.7
Notes: Direct access to the control output
setpoints is only available when the menu is
enabled - see section 5.5.9
Seconds are always displayed while adjusting the
setpoints.
5.6 APPLICATION
This section describes a typical application in
which a 24 hour clock with a HH:MM format is
required within a hazardous area. To comply with
auditing requirements, this, and a number of other
BA368C clocks are to be automatically
synchronised at 12:00 each day. To prevent
accidental adjustment the instrument programme
menu is to be protected by security code 1112
Fig 5.5 shows the simplest Zener barrier interface
and illustrates how a number of clocks may be
synchronised. Terminals 2 and 8 are
interconnected within the BA368C so only one of
them needs to be connected to the Zener barrier
busbar.
When the synchronising contact is closed all the
BA368C clocks will display the programmed reset
time, in this example 12:00. When the contacts
open all the clocks will start running. This contact
may be a PLC output programmed to close at
11:59:58 and to open at 12:00:00
Fig 5.5 Clock application with synchronisation