GE Multilin F650, Instruction Manual

Page: 251 / 1046

CHAPTER 5: SETPOINTS 5.4 PROTECTION ELEMENTS
GEK-106310-AF F650 DIGITAL BAY CONTROLLER 5-99
This way, when the function is enabled and the unbalance is produced over the set percentage, the element picks up. If
unbalance conditions are maintained during a period longer than the set time delay, the element trips.
In order to avoid trips or pickups with very weak loads there is a
current level threshold to inhibit the operation of the
element when the three phase currents are below a fixed level.
Note: The I2/I1 current inhibition level for the different firmware versions is as follows:
The Operation Threshold level has been included to allow the user selecting the current inhibition level suitable for a
particular application, in order to avoid operation of the element when the relay is not connected to the line or in case the
relay has previously operated correctly and has been disconnected from the line, as in this case the operation condition is
met but the relay should not trip.
The operation threshold operation is as follows:
The Broken conductor element is fully operational if at least one of the phase currents is higher than the setting. This
condition assumes that the relay is connected to the line.
If the element is on trip or pickup condition, the element is reset if the three phase currents are below the operation
threshold level. This condition assumes that the relay is not connected to the line and therefore the relay should not trip.
Due to the response time of this function, if the set time delay is 0s, a trip can occur in situations where, for example, one of
the currents is stopped before the rest, as these currents would produce a negative sequence current calculation.
Therefore, to avoid this kind of undesired trips, it is strongly recommended to establish a minimum time delay setting, such
as 100 ms, or higher depending on the expected normal unbalances in the network. This is to differentiate these situations
from broken conductor situations.
5.4.11.2 Locker rotor
F650 incorporates a locked rotor element (48) with three elements. Protection element produces a trip when current
(primary values) exceeds the set value. This current setting value is the product of the set Full load current by the pickup
setting.
Settings can be configured by using ENervista 650 setup at Setpoint> Protection Elements> Setting Group X>
Miscellaneous>Locked Rotor
Table 5-67: Locker rotor element settings
Trip Time Trip Delay 60.00 0.01 s [0.00 : 900.00]
Snapshot event generation Snapshot Events ENABLED N/A [DISABLED – ENABLED]
Current Inhibition Level setting Operation Threshold 0.005 0.001 A [0.000 : 1.000]
Firmware Version Current Inhibition Level
1.50 or Lower 10 mA
1.60 or Higher 50 mA
1.80 or Higher Selectable by setting from 0.000 to 1.000 in steps of 0.001 A
SETPOINT> PROTECTION ELEMENTS>SETTING GROUP X> MISCELLANEOUS>LOCKED ROTOR 1> LOCKED ROTOR
2> LOCKED ROTOR 3
setting Description
Name Default Value Step Range
Function permission Function DISABLED N/A [DISABLED – ENABLED]
Input type Input PHASOR (DFT) N/A [PHASOR – RMS]
Full load current Full Load Current 0.50 KA [0.10 : 10.00]
Pickup level Pickup Level 1.01 N/A [1.01 : 109.00]
Trip time Trip Delay 0.00 s [0.00 : 900.00]
Reset time Reset Delay 0.00 s [0.00 : 900.00]
Snapshot event generation Snapshot Events ENABLED N/A [DISABLED – ENABLED]