BEKA BA368C, Руководство пользователя

Страница: 57 / 93

57
3.6.4 Control output off at:
‘OP1:OFF’ and ‘OP2:OFF’
The control outputs may be programmed to turn off
(open)
when the timer is started, stopped, reset or
the elapsed time equals the programmed set time.
To define when a control output opens select
‘OP1:OFF’ or ‘OP2:OFF’ from the control output
sub-menu and press
P which will reveal the current
setting. Pressing the Up or Down button will scroll
through the four options:
Display Control output closes when
‘StArt’ The timer is started
‘StOP’ The timer is stopped
‘rESEt’ The timer is reset
‘SEt t’ The elapsed time equals set
time setpoint SEt t.
When the required option has been selected press
E to enter the selection and return to the control
output sub-menu.
Note: When the timer elapsed time equals the set
time ‘SEt t’, an internal stop signal is automatically
generated and all actions associated with STOP
are performed.
3.6.5 Output on delay time:
‘OP1:dELA’ and ‘OP2:dELA’
Both control outputs may be independently
delayed from turning-on for a fixed time following
the selected condition occurring. e.g. when the
timer is started. This delay can be programmed in
1 second increments up to 32,400 seconds, which
is 9 hours. If a delay is not required zero should
be entered. To adjust the delay select 'dELA' from
the control output sub-menu and press
P which will
reveal the existing delay time. Each digit of the
delay can be adjusted using the
Up and Down
push-buttons, and the P button to move to the next
digit. When the required delay has been entered,
press
E to return to the alarm menu.
When the delay function is used the front panel
control output annunciator will start flashing when
the programmed switching condition occurs. It will
continue flashing until the delay time has expired,
when the control output will close and the
annunciator will be continuously activated.
3.7 APPLICATIONS
The BA368C timer is a versatile instrument which
can perform a wide variety of hazardous area
timing applications. BEKA engineers will be
pleased to help with the design of your BA368C
timing system be it a simple manually controlled
stopwatch, or a more complicated control
application.
Figure 3.5 shows how a BA368C timer may be
used to measure how long a hazardous area
contact is closed. This illustrates how the timer
may be started and stopped by one input.
Fig 3.5 Starting & stopping timer with one input
The required programme parameters to achieve
this are shown below, others are not critical.
FunCtion ‘ELAPSE’ Timer
InPut A ‘ContACt’ Switch contact
StArStOP ‘ControL 4’ Closure operates
The second example in Fig 3.6 shows how the
timer may be configured to open an intrinsically
safe solenoid valve for a defined time. When the
start button is operated the timer starts to count up
and control output 1 is closed which opens the
solenoid valve. In this example the stop button
functions as a pause control which closes the
valve until the start button is again operated.
When the total elapsed time equals the set time,
‘SEt t’, control output 1 opens thus closing the
solenoid valve.
In this example control output 2 has been wired to
the timer reset terminals and programmed with a
five seconds control output delay. Therefore five
seconds after the timing cycle has been completed
the system automatically resets and is ready for
the next timing cycle.