Per Element Detection

Sectionalise

An element configured to Sectionalise will pick up when it sees a fault and log a fault detection when it times out. If that fault detection leads to a supply interrupt it will increment the Supply Interrupt count.

Alarm

An element that is configured to alarm only will still pick up if it sees a fault but will only generate an alarm when it times out and not cause a fault detection.

It may still lead to a supply interrupt being logged for each faulted element but they will not increment the Supply Interrupt count and therefore will not cause the AS to sectionalise.

OFF

An element that is configured Off will not cause a pickup. Consequently that element cannot cause a fault detection, supply interrupt or sectionaliser trip.

When Extended Standard Detection is also enabled, it provides the operator the option to configure different Sectionalise and Alarm settings on a per group basis.

Making the feature available

In order to use this feature, Per Element Detection must be made available by the operator via the WSOS Feature Selection menu.

The Feature Selection menu can be found by navigating through:

Display > Configuration > Feature Selection.

Configuration

Once this feature has been enabled, the operator will be able to configure the actions required for each detection element, either Off, Alarm or Sectionalise.

These options are available for the following detection elements:

• Phase Fault

• EF

• SEF

• NPS

SEF Alarm and Single Shot Mode On/Off settings are also included.

The additional settings are displayed on the WSOS Control page shown in the figure below.

Figure 187
Per Element Detection settings

Per Element Detection adds 8 pages to the flexVUE operator interface.

And are displayed on two page on the setVUE operator interface.

The table below describes the changes that occur with the detection elements affected when Per Element Detection is enabled. It assumes that Detection is On, SEF Detection is available, Sequence Components are available and NPS Off is allowed.

Supply Interrupt Flags

When Per Element Detection is available, Supply Interrupt Flags are displayed by WSOS and the O.I. on the controller.

If a fault resets and the upstream device trips within the Supply Fail Time, a Supply Interrupt Flag for the faulted element/phase will be set.

The Supply Interrupt Flag is an indication that the fault was downstream of the AS that is it performs the function of a fault passage indicator.

The Supply Fail Time is 3.0 s by default and configurable between 1.0 and 60.0 s in 0.1 s steps.

This setting is available in WSOS on the Universal Settings page.

Figure 188
Supply Fail Time setting

The Supply Fail Time setting can also be configured on the operator interface.

Supply Interrupt Flags are displayed for the following elements providing they are available:

• A Phase Overcurrent

• B Phase Overcurrent

• C Phase Overcurrent

• EF

• SEF

• NPS

The conditions required to activate a Supply Interrupt Flag are:

1. Fault detection.

2. Fault reset.

3. Source supply goes to zero volts within the Supply Fail Time following step 2.

Once a Supply Interrupt Flag has been set, it can be cleared by any of the following:

• Any switchgear close.

• Any phase current above 2 amps.

• Any phase to Earth voltage above the Live Line Threshold on both sides.

Alarms generated by this feature are available for transmission via SCADA.

In addition to the SCADA alarm point, the Supply Interrupt Flags are available on the WSOS Fault Flags page in the Display menu.

Figure 189
Automatic Sectionalise Supply Interrupt Flags

And also on the operator interface.

The Supply Interrupt Flags will operate whether Detection is On or Off.