Instructional Literature
Page
156
Effective: May 2008
Instructions for the FP-6000 Protective Relay
For more information visit: www.eaton.com
IB02602004E
Table 42. Voltage Protection Settings.
8.6.3 Neutral Overvoltage (59N)
The FP-6000 includes a protective function for detecting neutral
overvoltage conditions. Two elements are provided for each
function; allowing alarm and trip levels to be set independently.
Each of the neutral overvoltage functions have four settings
associated with it.
The 59N threshold can be based on either the measured voltage
through Vx or based on internally calculated residual voltage. If
the measured voltage is selected, the 59N is similar to 59A; the
only difference is in this case the 59N threshold will be based on
either phasor or rms at the user’s discretion, while 59A uses rms.
Note: the phasor reflects only the fundamental frequency
component while rms includes all frequencies.
If the calculated voltage is selected, the setting of criterion will
make no difference and the phasor will be used for the threshold.
Note:
if the voltage connection is delta, there will be no zero sequence
voltage, therefore 59N function will not act.
The settings for the neutral overvoltage functions are shown in
Section 5 - Programming and are repeated in the table below.
Table 43. Neutral OV Protection Settings.
8.6.4 Loss of Potential
The FP-6000 includes the Loss of Potential logic for detecting loss
of any phase of the voltage measuring circuits, see Figure 52.
Once the loss of potential condition is identified the LOP will be
set.
The LOPB bit may also be set if the LOPB is selected to be
enabled. Once the LOPB is set the voltage restraint function of
51P2 overcurrent and underpower function will be automatically
blocked. Both LOP and LOPB are the options of the
programmable logic input.
All the current elements can be blocked through their block gate
logic and other functions may be blocked through the
programmable logic if the user desires. The LOP logic allows a
window of opportunity to override LOPB if a fault occurs within a
certain time period just after LOP is identified.
The settings for the neutral overvoltage functions are shown in
Section 5 - Programming and are repeated in Table 44.
Table 44. Loss Potential Settings.
PARAMETER
RANGE
STEP
59-M1 Main
Overvoltage Phase
Any One, Any Two,
All Three
59-M1 Main
Overvoltage Threshold
10 to 150 V,
Disabled
1 V
59-M1 Main
Overvoltage Delay
0 to 9999 Cycles
1 Cycle
59-M2 Main
Overvoltage Phase
Any One, Any Two,
All Three
59-M2 Main
Overvoltage Threshold
10 to 150 V,
Disabled
1 V
59-M2 Main
Overvoltage Delay
0 to 9999 Cycles
1 Cycle
27-M1 Main
Undervoltage Phase
Any One, Any Two,
All Three
27-M1 Main Under-
voltage Threshold
10 to 150 V,
Disabled
1 V
27-M1 Main
Undervoltage Delay
0 to 9999 Cycles
1 Cycle
27-M2 Main Under-
voltage Phase
Any One, Any Two,
All Three
27-M2 Main Under-
voltage Threshold
10 to 150 V,
Disabled
1 V
27-M2 Main
Undervoltage Delay
0 to 9999 Cycles
1 Cycle
59-A1 Auxiliary
Overvoltage
Threshold
10 to 250 V,
Disabled
1 V
59-A1 Auxiliary
Overvoltage Delay
0 to 9999 Cycles
1 Cycle
59-A2 Auxiliary
Overvoltage
Threshold
10 to 250 V,
Disabled
1 V
59-A2 Auxiliary
Overvoltage Delay
0 to 9999 Cycles
1 Cycle
27-A1 Auxiliary
Undervoltage
Threshold
10 to 250 V,
Disabled
1 V
27-A1 Auxiliary
Undervoltage Delay
0 to 9999 Cycles
1 Cycle
27-A2 Auxiliary
Undervoltage
Threshold
10 to 250 V,
Disabled
1 V
27-A2 Auxiliary
Undervoltage Delay
0 to 9999 Cycles
1 Cycle
PARAMETER
RANGE
STEP
59N-1
Overvoltage
Source
Calculated,
Measured
59N-1
Overvoltage
Criterion
Phasor, rms
59N-1
Overvoltage
Threshold
5 to 250 Volts,
Disabled
1 V
59N-1
Overvoltage
Delay
0 to 9999 cycles,
Disabled
1 Cycle
PARAMETER
RANGE
STEP
LOP Block
Disable,
Enable
Alarm Delay
0 to 9999 Cycles,
Disable
1 Cycle
