CHAPTER 5: SETTINGS
INPUTS/OUTPUTS
N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL
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5
5.9 Inputs/outputs
5.9.1 Contact inputs
SETTINGS
INPUTS/OUTPUTS
CONTACT INPUTS
A contact inputs and outputs are digital signals associated with connections to hard-wired contacts. Wet and dry contacts
are supported.
The contact inputs menu contains configuration settings for each contact input as well as voltage thresholds for each
group of four contact inputs. Upon startup, the relay processor determines (from an assessment of the installed modules)
which contact inputs are available and then display settings for only those inputs.
An alphanumeric ID can be assigned to a contact input for diagnostic, setting, and event recording purposes. The
CONTACT IP
X On
(Logic 1) FlexLogic operand corresponds to contact input “X” being closed, while
CONTACT IP X Off
corresponds to contact
input “X” being open. The
CONTACT INPUT DEBNCE TIME
defines the time required for the contact to overcome ‘contact
bouncing’ conditions. As this time differs for different contact types and manufacturers, set it as a maximum contact
debounce time (per manufacturer specifications) plus some margin to ensure proper operation. If
CONTACT INPUT EVENTS
is
set to “Enabled,” every change in the contact input state triggers an event.
A raw status is scanned for all Contact Inputs synchronously at the constant rate of 0.5 ms as shown in the following
figure. The DC input voltage is compared to a user-settable threshold. A new contact input state must be maintained for a
user-settable debounce time in order for the N60 to validate the new contact state. In the following figure, the debounce
time is set at 2.5 ms; thus the 6th sample in a row validates the change of state (mark no. 1 in the diagram). Once validated
(de-bounced), the contact input asserts a corresponding FlexLogic operand and logs an event as per user setting.
A time stamp of the first sample in the sequence that validates the new state is used when logging the change of the
contact input into the Event Recorder (mark no. 2 in the figure).
CONTACT INPUTS
CONTACT INPUT H5a
CONTACT INPUT H5a ID:
Cont Ip 1
Range: up to 20 alphanumeric
characters
CONTACT INPUT H5a
DEBNCE TIME: 6.0 ms
Range: 0.0 to 16.0 ms in steps of 0.5
CONTACT INPUT H5a
EVENTS: Disabled
Range: Disabled, Enabled
↓
CONTACT INPUT xxx
CONTACT INPUT
THRESHOLDS
Ips H5a,H5c,H6a,H6c
THRESHOLD: 33 Vdc
Range: 17, 33, 84, 166 Vdc
Ips H7a,H7c,H8a,H8c
THRESHOLD: 33 Vdc
Range: 17, 33, 84, 166 Vdc
↓
Ips xxx,xxx,xxx,xxx
THRESHOLD: 33 Vdc
Range: 17, 33, 84, 166 Vdc