4
CONTROL / ALARM STATUS UNDER PV ERROR CONDITIONS
a) The tuning, if in progress, is aborted.
b) The Profile Cycle, if in progress, enters in HOLD state.
c) Under
Over-range
or
Under-range
error condition, all the control outputs are switched off. However, under
Sensor Open
error, the PID control output power is maintained at the value set for the parameter “Sensor Break Output Power” on
PAGE-12.
d) For Alarm activation, the under-range condition is treated as minimum PV, whereas the over-range and open conditions
are treated as maximum PV. Thus, Process High, positive Deviation Band and Window Band alarms activate under
Over-
range/Open error
. Similarly, Process Low, negative Deviation Band and Window Band alarms activate under
Under-
range error
.
STANDBY MODE
This mode allows the operator to put the controller in ‘
indication-only
’ mode wherein all the output control signals as well as
Alarm Relays are forced OFF. This may be desired prior to the start of a new process batch.
If enabled at supervisory level, the standby mode can be activated or de-activated by setting the parameter ‘Standby’ to Yes or
No respectively. The standby parameter is available on operator page, explained later in the section.
Notes:
1. The Standby and Tuning modes are mutually exclusive. If Standby mode is activated while the controller is tuning, the controller aborts
tuning operation and enters Standby mode.
2. If the Power Supply to the controller is switched-off or a Power-failure occurs while the controller is operating in Standby mode; upon
resumption of power, the controller continues to operate in Standby mode.
OPERATOR PAGE AND PARAMETERS
The controller provides a separate page that contains parameters that require frequent settings by the operator. The page is
called
Operator Page
and the parameters are called
Operator Parameters
. The availability of operator parameters is
controlled at supervisory level and the parameter setting is not affected by the master lock status.
Accessing Operator Page & Adjusting Parameters
Step through the following sequence to open the operator page and to adjust the operator parameter values.
1. Press and release PAGE key. The Lower Readout shows (PAGE) and Upper Readout shows (0).
2. Press ENTER key. The Lower Readout shows prompt for the first available operator parameter and the Upper Readout
shows value for the parameter.
3. Use UP / DOWN keys to adjust the value and then press ENTER key to store the set value and scroll to next parameter.
The controller automatically reverts to MAIN Display Mode upon scrolling through the last operator parameter. Alternatively,
use PAGE key to return to MAIN Display Mode.
The operator parameters are described in Table 2.2. Note that the parameters presented on operator page depend upon the
functions selected/enabled and supervisory level permissions.
The operator parameter list mainly includes :
a) Profile related commands like Start, Abort, Pause, Skip etc.
b) Standby mode entry / exit.
c) Control Setpoint (SP) value.
d) Alarm-1 Setpoint / Band values.
e) Alarm-2 Setpoint / Band values.
User Manual
EPSILON
