Protective function configuration – Siemens ISGS SG8158-00 User Manual
Page 32
Protective Function Configuration
26
Siemens Energy & Automation, Inc.
The range of the pickup value (2003) depends on the sec-
ondary phase neutral CT rating (1 A or 5 A) and the value is in
secondary amperes. The function begins timing when any
individual neutral current exceeds the pickup current setting.
Note: The pickup point is 1.06 of the pickup set-
ting. Refer also to paragraph on Pickup in
Section 5.1.
The Time Dial (2005) used for the selected curve allows the
time-to-trip of the curve to be raised or lowered The dial can
be adjusted from 0.1 to 9.9 in steps of 0.1.
The Filter (2006) sets the sensing method used by the func-
tion in its pickup calculations. The rms filter uses fundamen-
tal current plus harmonics, while the fundamental filter
ignores harmonics.
Impedance (2007) sets the angle used by this function. It
determines the direction of current flow being measured and
can be set from 0 to 90 degrees. The directional characteris-
tic (line) in the complex impedance plane is shown in
Figure 5.2. The directional characteristic is always perpen-
dicular to the line impedance vector.
The sensing direction (2008) can be set to forward or
reverse. The forward setting allows the directional protection
element to pickup on fault current only in the direction of nor-
mal power flow.
Each of the two waveform capture buffers (2010 and 2011)
can be independently programmed to freeze snapshots on
pickup or trip.
The Directional Neutral or Ground Time Overcurrent function
is able to actuate any binary output contact on pickup, and
any trip or binary output contact on trip.
5.11 Overvoltage (59)
The Overvoltage function causes a trip if the rms value of any
of the line voltages exceeds a set level. This function is only
available if the voltage input option is installed.
A2200 Overvoltage (59)
Address Parameter
Option
2201 Function
Enabled or Disabled
2202 Curve
Definite
Inverse
Moderately Inverse
Very Inverse
2203 Pickup Source V
Line-to-ground
Line-to-line
2204 Pickup
60-250 V (0.1 V steps)
2205 Time Delay (Def.)
0.1-60 s (0.01 s steps),
or infinity
2205 Time Dial (Inverse)
0.1-9.9 (0.1 steps)
2210 Freeze Wfm2
on Pickup, on Trip, or None
2211 Freeze Wfm2
on Pickup, on Trip, or None
The Overvoltage function can be enabled or disabled (2201).
The Curve parameter (2202) allows the selection of a definite
time delay or a characteristic curve. When the definite time
characteristic is selected, the time delay begins as soon as
the device goes into pickup. The inverse time characteristic
utilizes a moderate inverse curve using the time dial.
The Pickup Source Voltage parameter (2203) indicates the
VT connection. If the VTs are connected line-to-ground, the
device can pickup on line-to-line or line-to-ground voltages.
If the VTs are connected line-to-line, the VTs can only pickup
on line-to-line voltages. The maximum continuous voltage
across a VT input is 150 VAC.
The pickup value (2204) is in secondary volts ranging from
60 to 250 V. The function begins timing when any individual
phase voltage exceeds the pickup voltage setting.
The time delay (2205) represents the time between pickup
and trip and can be set when definite time is selected. The
delay can be adjusted from 0.1 to 60.0 seconds in steps of
0.01 second. If the function remains in pickup for longer than
the time delay, the function causes a trip. The delay can also
be set to infinity so that the function never times out.
The Time Dial parameter (2206) is used for the characteristic
curve. The dial allows the time-to-trip of the curve to be
raised or lowered. It can be adjusted from 0.1 to 9.9 in steps
of 0.1.
Each of the two waveform capture buffers (2210 and 2211)
can be independently programmed to freeze snapshots on
pickup or trip.
The function is able to actuate any binary output contact on
pickup, and any trip or binary output contact on trip.
5.12 Undervoltage (27)
The Undervoltage function causes a trip if the rms value of
any of the line voltages falls below a set level and can be use-
ful for capturing power quality disturbances. This function is
only available if the voltage input option is installed.
2300 Undervoltage 27
Address Parameter
Option
2301 Function
Enabled or Disabled
2302 Curve
Definite
Inverse
Moderately Inverse
Very Inverse
2303 Pickup Source V
Line-to-Neutral or Line-to-Line
2304 Pickup
40-230 V (0.1 V steps)
2305 Time Delay (Def.)
0.1-60 s (0.01 s steps),
or infinity
2305 Time Dial (Inverse)
0.1-9.9 (0.1 steps)
2310 Freeze Wfm 2
on Pickup, on Trip, or None
2311 Freeze Wfm 2
on Pickup, on Trip, or None
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