Table of Contents
Advertisement
I.L. 40-386.3
The fault distance calculation is as follows:
Flt Dist
Where Z
3.3.9
Distance Type (DistUnit) Setting
Distance type has a selection of MILE and KM. It should be selected to match with the
setting of X / Dist. For this example, select DistUnit = MILE.
3.3.10 Reclosing Mode (RI Type) Setting
RI Type is for selecting the reclosing mode. It has four selecting positions (No RI/ ØG
RI / ØØ, ØG RI/ 3Ø, ØØ, ØG RI). Refer to the guidelines for reclosing mode program-
ming for the RI Type setting selection.
3.3.11 Reclose Initiation Settings
Fast RI, Zone2 RI and Zone3 RI provide the selectivity for High speed tripping unit,
Zone2 and Zone3 reclosing initiation, respectively.
3.3.12 Remote Breaker Failure, Reclose Block (RemBF RB)
For a pilot system (REL 302 only), set RemBF RB to YES if reclose block output for
the breaker failure squelch feature is required.
3.3.13 Remote Pilot Control (Pilot) Setting
Pilot set to Yes combines with the signal of Pilot Enable (external 85CO input) and
controls the operation of pilot logic tripping and reclosing initiation. The absence of ei-
ther signal will disable the pilot system logic.
The Pilot setting can be set either locally from the front panel, or via the communica-
tion interface or remotely.
3.3.14 System Type Selection (SystType)
SystType selects the desired relaying system for the application. REL 301 has two set-
ting choices: Non Pilot and Zone1 Extension. REL 302 has five setting choices: Non Pi-
lot, Zone1 Extension, POTT (permissive overreach transfer trip), PUTT (permissive
underreach transfer trip) and Blocking (directional comparison blocking). It should be
set to the desired mode of operation.
3.3.15 For The Pilot REL 302 Only
a.
3-Term. (3 terminals) setting should be selected to YES for all three terminals that apply.
b.
Weakfeed (weakfeed terminal logic enable) selection should be set to YES for the
weakfeed terminal, if applicable.
c.
For Application Of POTT or Blocking, systems, the transient block logic is always automat-
ically enabled and is initiated by the reverse looking units. The Zone3 to Reverse Dir. and
Zone3 Ø, and Zone3 G should be set to 100% of the reverse line impedance.
3-10
×
∠
Z
sin
FANG
VT Ratio
S
×
=
------------------------- -
------------------------------------------- -
CT Ratio
X / Dist
is the secondary impedance magnitude, and FANG is the fault angle.
S
(10/94)
Advertisement
Table of Contents
