Despatch P1400+ Temperature Controller - Manual (Page 85)

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Loop Alarm Time Type: Controller Parameter
When On-Off control is selected and loop alarm is enabled, this parameter determines the duration
of the limit condition after which the loop alarm will be activated. It may be adjusted within the range
of 1 second to 99 minutes 59 seconds. This parameter is omitted from the Set-up mode display
sequence if On-Off control is not selected or loop alarm is disabled.
Display code =
LAti , Default setting is 99:59.
Also refer to Loop Alarm Enable .
mADC Type: General Definition
This stands for milliamp DC. It is used in reference to the DC milliamp input ranges and the linear
DC milliamp outputs. Typically, these will be 0 to 20mA or 4 to 20mA.
Manual Mode Type: Controller Definition
If Manual Mode is enabled in Set-Up mode, pressing the AM key in operator mode will cause a
controller to enter or leave manual control mode. Switching between automatic and manual modes
is achieved using bumpless transfer.
For standard Process Controllers Manual Mode operates as follows:
The upper display shows the current process value, and the lower display shows the output power in
the form -
P xxx (where xxx is equal to the percentage output power). This value may be adjusted
using the UP or DOWN keys to increase/decrease the power output. The value can be varied
between 0% to 100% for controllers using primary control only, and -100% to +100% for controllers
using primary and secondary control (e.g. full heat power to full cool power).
Manual Mode should be used with care because the power output level is set by the operator,
therefore the PID algorithm is no longer in control of the process. The operator MUST maintain the
process as the desired level manually. Manual power is not limited by the Primary Power Output
Limit.
Also refer to
Bumpless Transfer , Manual Mode Enable , PID , and Primary Output Power Limit .
Manual Mode Enable Type: Controller Parameter
Determines whether operator selection and de-selection of manual control is enabled. If the mode is
enabled in Set-Up mode, pressing the AM key in Operator Mode will normally activate or deactivate
manual control mode. However, disabling
poen in while manual control mode is active will lock the
controller into Manual Mode and pressing the Auto/Man key will no longer cause a return to PID
(automatic) control. To exit from Manual Mode,
poen must temporarily be re-enabled to allow PID
control to be re-established. poen can then be safely disabled.
It is possible to use a controller as a permanent “Manual Station” by disabling poen to deliberately
lock it into Manual Mode.
Manual Mode can also be selected using a digital input if one has been fitted and configured for this
function. When in Manual Mode, the MAN LED indicator flashes.
Display code =
PoEn , default setting = diSA
....
Also refer to Manual Mode and PID
Master & Slave Type: Controller Definition
The terms master & slave are used to describe the controllers in applications where one instrument
controls the setpoint of another. The master controller can transmit the setpoint to the slave using an
analogue DC linear signal. The slave controller must have a matching a remote setpoint input. Some
Profile Controllers can transmit their setpoint via serial communications serial communications. For
this method, the Profiler must be able to act as a communications master device and the slave must
have a compatible communications option fitted.