Issue 2, Nov-98. Applies to software versions 1.3 & 1.4 -7- HA026270
..........Timer Operating Modes continued
- Mode 3, Time from Cold and Switch Off
This is the same as mode 1 except that the timer will start counting
down immediately without waiting for the temperature to reach
setpoint.
Mode 4, Time from Cold No Switch Off
This is the same as mode 2 except that the timer will start counting
down without waiting for the controller to reach setpoint.
Mode 5, Delayed Switch On
This mode applies a time delay before turning on the heating (or
cooling). When the timer is started, the controller will always
switch to standby mode and start counting down. When the timer
has timed out, the controller will switch into automatic control,
apply heating (or cooling) and control indefinitely at the setpoint.
To Program a Ramp-Dwell profile
A simple ramp-dwell profile can be programmed using
(setpoint rate limit) in combination with the timer. To use this
feature, first reveal
and (the working setpoint) using
the method described in “To Hide, Reveal and Promote”
parameters.
will then appear in the HOME list.
Set
to the required ramp rate It is adjustable in 1/10
th
of
the least significant display units per minute. That is if the display
is configured 0 to 1000
o
C, setpoint rate limit can be adjusted
between 0.1 and 999.9
o
C per minute.
When setpoint rate limit has been enabled and the timer is started,
the working setpoint,
, will first step to the measured
temperature and then ramp at the setpoint rate limit,
, to the
target setpoint.
In modes 1 and 2 timing will start when the measured temperature
is within 1
o
C of the target setpoint. In modes 3 and 4 it will start
when
is within 1
o
C of the target setpoint.
T
O
S
TART
A
ND
R
ESET
T
HE
T
IMER
There are two methods:
Method 1.
This is the simplest method to control the timer.
•
Press
until you reach the
list
•
Press
until you reach the
parameter (time
remaining).
TIP: Promote
to the HOME list for quick access, as
described in ‘To Hide, Revealing and Promote Parameters.
As soon as a value is entered into
timing will commence.
will count down towards zero. During the timing period
can be increased or decreased according to the demands of the
process. Setting the value to zero will end the timing period.
When
reaches zero. ‘’ will flash in the main display.
The timer will remain indefinitely in this state until a new value is
entered, when the timer will restart.
To reset the timer, press and
together. ‘
’ will stop
flashing .
To restart the timer, enter a new value into
Method 2.
Use this method if you want to set a fixed time and use the
parameter to start and stop the timer.
The
parameter can also be switched between and
by configuring the logic I/O as a Off/run contact closure
input.
Open the external contact to select
. This is an edge triggered
action. Close the contact to select
. is forced whenever
the contact is closed.
Press
or
to enter the
required timing period in minutes.
(0 to 9999).
Press to return to the HOME display
Press
to reach the
List
heading.
Press until you reach
Dwell time
Press
or
to enter a
timing period in minutes
(0-9999).
Timer Status
To start the timer, press
or
to select
.
The dwell time will be loaded into
and timing will commence.
To reset the timer, select
.
The time remaining
will be set
to
.
Press
and
together to return to the HOME display.
Standby mode
Temperature
Setpoint
Reset
Timing
End
flashes
Temperature
Setpoint
Reset
Timing
End
flashes
Indefinite dwell at
setpoint
Indefinite dwell at
setpoint
Temperature
Setpoint
Reset
Timing
Reset
