
D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
617
D90
Plus
Line Distance Protection System
Chapter 14: Testing
Testing
This section describes the D90
Plus
testing features.
Test mode
The D90
Plus
provides test settings to verify that functionality using simulated conditions for
contact inputs and outputs. To initiate the test mode, the
Test Mode Function
setting must
be “Enabled” and the operand assigned to the
Test Mode Initiate
setting must be set to
logic 1.
In particular, the test mode is initiated as follows.
•
To initiate test mode through the D90
Plus
settings, set the
Test Mode Initiate
to “ON”.
The test mode starts when the
Test Mode Function
setting is changed from “Disabled”
to “Enabled”.
•
To initiate test mode through a user-programmable condition, such as FlexLogic™
operand, set the
Test Mode Function
setting to “Enabled” and the
Test Mode Initiate
to
the desired operand. The test mode starts when the selected operand assumes a logic
1 state.
When in the test mode, the D90
Plus
remains fully operational, allowing for various testing
procedures. The only difference between the normal operation and the test mode is the
behavior of the input and output contacts. The former can be forced to report as open or
closed or remain fully operational; the latter can be forced to open, close, freeze, or remain
fully operational. The response of the digital input and output contacts to the test mode is
programmed individually for each input and output using the force contact inputs and
force contact outputs test functions described in the following sections.
Force contact inputs
The force contact inputs feature provides a method of performing checks on the function
of all contact inputs. Once enabled, the D90
Plus
is placed into test mode, allowing this
feature to override the normal function of contact inputs. All contact input operations
return to normal when all settings for this feature are disabled.
Select the
Settings > Testing > Force Contact Inputs
menu item to open the force contact
inputs configuration window.