9328900990 Rev L BE1-951 Protection and Control 4-41
Table 4-23. BESTlogic Settings for Auxiliary Undervoltage/Overvoltage
Function Range/Purpose Default
Mode
0 = Disabled
1 = Fundamental Vx Input
2 = 3Vo Phase Inputs ∗
3 = 3
rd
Harmonic, Vx Input
0
BLK
Logic expression that disables function when TRUE. A setting of 0 disables
blocking.
0
∗ To use Mode 2, the VTP connection must be 4-wire. Optional Auxiliary Input must be present to use
Mode 1 or Mode 3.
Operating Settings for Auxiliary Undervoltage/Overvoltage
Operating settings for the 27X and 59X/159X functions consist of pickup and time delay values. The
pickup value determines the level of voltage required for the element to start timing toward a trip. Unit of
measure is secondary volts (PP or PN) and depends on the SG-VTX setting see
Table 4-24. For more
information, refer to Section 3, Input and Output Functions, Power System Inputs. The time delay value
determines the length of time between pickup and trip. Time delays can be set in milliseconds, seconds,
or cycles. The default is milliseconds if no unit of measure is specified.
Table 4-24. VTX Connection Settings
VTX Connection Mode Unit
AB, BC, CA 1 or 3 VPP
AN, BN, CN 1 or 3 VPN
GR 1 or 3 VPN
Any 2 VPN
Operating settings are made using BESTCOMS.
Figure 4-34 illustrates the BESTCOMS screen used to
select operational settings for the Auxiliary Overvoltage elements. To open the Voltage Protection screen
for Under/Overvoltage elements, select Voltage Protection from the S
creens pull-down menu. Then select
the 59X/159X tab. (The Auxiliary Undervoltage [27X] element is set in a similar manner using the 27X
tab.) Alternately, settings may be made using the S<g>-59X, S<g>-159X, and S<g>-27X ASCII
commands.
To Next Page
Loading...
Need help?
General