BECKWITH ELECTRIC M-3520, Instruction Book

Page: 63 / 217

2–30
M-3520 Instruction Book
59 Overvoltage, 3-Phase
Voltage is commonly suggested as an efficient
means to protect against islanding. Notably, unless
the Dispersed Generation (DG) includes very
high-speed generator excitation response, the island
case where load is less than generation will result
in a rapid rise of voltage. Except for those systems
prone to ferroresonance, the voltage waveform will
remain essentially sinusoidal, making the use of
rms value of the fundamental frequency component
as the measurement.
IEEE suggests that the first setpoint (with a short
time delay) be set up at 150% of the nominal voltage,
and the second setpoint (with a long time delay) be
set at 106 to 110% of the nominal voltage to prevent
nuisance trips (
Intertie Protection of Consumer-
Owned Sources of Generation, 3 MVA or Less;
IEEE Publication 88TH0224-6-PWR).
Save
Cancel
@ : WARNING, Function DISABLED until output selected!
(59) - OVERVOLTAGE
Pickup:
Delay:
5 V
1 Cycle
180 V
8160 Cycles
#1
OUTPUT
8 7 6 5 4 3 2 1 FL 6 5 4 3 2 1
Blocking Input @
Pickup:
Delay:
5 V
1 Cycle
180 V
8160 Cycles
#2
OUTPUT
8 7 6 5 4 3 2 1 FL 6 5 4 3 2 1
Blocking Input @
Figure 2-20 M-3822 IPScom
®
for Windows™ Phase Overvoltage (59) Setpoint Ranges
Path : Relay Menu/Setup/Setpoints/(59) Phase Overvoltage
COMMAND BUTTONS
Save Saves all information to the relay.
Cancel Returns the user to the previous window; any changes to the displayed information are lost.
If this function is enabled, the following settings are applicable:
59 #1 PICKUP
________ Volts
59 #1 DELAY
________ Cycles
59 #2 PICKUP
________ Volts
59 #2 DELAY
________ Cycles
Pickup and Time Delay settings for 59 function. Set
typically at 130% to 150%
Set typically at 3 to 6 cycles.
Set typically at 106% to 110%.
Set typically at 30 to 60 cycles.