36
CTI Janus Programmable Automation Controller IOG
5.3
Clear Exception Pushbutton Operation
When enabled, the
C
LEAR
E
XCEPTION
pushbutton provides a direct method to clear exceptions, reset controller
configuration values to default values, or restore factory defaults without requiring access to
Janus Workbench
or
the controller web server. In cases where the user selected password(s) for web server access is lost, this is the
only method that can used to clear existing passwords. No universal or developer-
embedded “back door”
password is allowed in the system. All pushbutton operations are logged in the controller event log. The CLEAR
EXCEPTION pushbutton will function only when Switch 3 is in the CLOSED (ON) position.
The following actions may be initiated by depressing the
C
LEAR
E
XCEPTION
button:
•
C
LEAR
E
XCEPTION
Pressing and holding the recessed pushbutton for greater than 5 seconds causes the Janus controller to
reset and return to normal operation following a System Exception.
When the button is pressed for one second, the front panel display shows countdown for ‘seconds to
controller reset’ (4
-1). If the pushbutton is released any time during this period, the operation is aborted.
If the button remains pressed until the countdown reaches zero, the display changes to
rE (
indicating
pending reset). Releasing the button at this time initiates the controller reset.
If the controller is in
RUN
or
LOGIC STOP
state when the
C
LEAR
E
XCEPTION
event is detected, the application
must be halted before the reset is triggered.
The controller startup operation following the reset is specified by
Operation following Module Reset
setting in C
ONFIGURATION
/G
ENERAL
S
ETTINGS
•
R
ESET
C
ONFIGURATION
S
ETTINGS
Pressing and holding recessed pushbutton for greater than 10 seconds causes the controller to reset,
returning all configuration settings to their default settings.
The following settings are reset by this action:
•
Startup Mode
•
Alphanumeric Display Options
•
Method for Setting IP Address
•
IP Address / Subnet Mask (all configured)
•
Web Server Password Protection Enable and associated Username/Password List
•
PLC Clock Time Set / Sync Method and associated settings
After the button is pressed and held for 5 seconds, the display will show
rE
(see
C
LEAR
E
XCEPTIO
N
description above). If the button press is maintained for another second, the front panel display shows
countdown for ‘seconds to
C
ONFIGURATION
R
ESET
’
(4-1). If the pushbutton is released any time during this
period until countdown reaches zero, the button press is treated as a
C
LEAR
E
XCEPTION
event as described
above.
If the button press is held until the
C
ONFIGURATION
R
ESET
countdown completes, the display changes to
Cr
(indicating pending
C
ONFIGURATION
R
ESET
). Releasing the button at this time initiates the
C
ONFIGURATION
R
ESET
event.
If the controller is in
RUN
or
LOGIC STOP
state when the
C
ONFIGURATION
R
ESET
event is detected, the
application will be halted and operational data stored (equivalent to ending the application from
Workbench) before the reset is triggered.
