ABB REL-300, Инструкция

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I.L. 40-385.1B
(5/92) 3-9
• Three-pole-trip and reclosing block on “sound
phase fault” (S
φ
F) during single-phasing.
• Three-pole-trip and reclosing block when the sin-
gle phasing limit timer (62T, 300-5000,in 50 ms
steps) is timed out to prevent overheating on gen-
erator(s).
When applying SPT, the functional display TTYP
settings (OFF/3PR/SPR/SR3R) provide the follow-
ing operating modes (in Table 3-3).
3.4.19 Oscillographic Data (Optional)
The oscillographic data has 8 samples per cycle, 1
cycle pre-trigger and 7 cycles post-trigger. It in-
cludes 16 events and 24 digital intermediate targets
(test points). The data can be accessed via the com-
munication port.
The oscillographic data is controlled by the selection
of TRIP/Z2TR/Z2Z3/dVdI in the OSC function,
where:
TRIP ---start data taken only if trip action occurs
Z2TR ---start data taken if Zone 2 units pick up or
any trip action occurs.
Z2Z3 ---start data taken if Zone 2 or Zone 3 units
pick up, or any trip action occurs.
∆
V
∆
I ---start data taken if
∆
I,
∆
V, Zone 2 or Zone 3
units pick up, or any trip action occurs.
NOTE: See 4.9 for dVdI setting.
3.5 PILOT SYSTEM
The MDAR functional display (see Section 4, Table
4-1, Sheet 1 of 3) Function Field “STYP” is used for
pilot system selection, as follows:
• Non-pilot, 3 zone distance
• Zone 1 extension (non-pilot)
• POTT (Permissive Overreach Transfer Trip/
Simplified Unblocking).....(pilot)
• PUTT (Permissive Underreach Transfer
Trip).....(pilot)
• BLK (Blocking).....(pilot)
• POTT or Simplified Unblocking Weakfeed.....(pi-
lot)
The following settings are recommended for POTT
and BLOCKING systems:
OSC - Z2Z3
FDAT - TRIP
FDGT - longer than 3 cycles
PLTP/PLTG - 150% overreach the next bus
Z1P/Z1G
- 80% of the protected line
Z3P/Z3G - 100% of the reversed line
Z3FR - REV
3.5.1 Permissive Overreach Transfer Trip
(POTT)/Simplified Unblocking
If the functional display “STYP” is set at the POTT
position, MDAR will perform either the POTT
scheme or the Simplified Unblocking scheme, de-
pending on the applied pilot channel.
The basic operating concepts of a POTT scheme
are:
(1) Pilot relays (PLTP/PLTG) are set to over-
reach the next bus.
(2) Pilot channel is a frequency shift type device;
its signal may be through either metallic wire
or microwave.
3) Transmitter frequency should be different at
each terminal: channel is normally operated
on a guard frequency; and the channel fre-
quency will be shifted from guard to trip when
the pilot relay(s) are operated; and pilot trip
is performed when the pilot relay(s) oper-
ate(s) and a pilot trip frequency signal from
the remote end is received.
The basic operating concepts of a Simplified Un-
blocking scheme are the same as the POTT
scheme, except for differences in application.
Pilot channel is a frequency-shift type power line car-
rier. The transmitter frequency must be different at
each terminal. It is normally operated on a blocking
frequency and will be shifted to an unblocking fre-
quency when the pilot relay(s) operate(s). The carri-
er receiver should provide logic for which, in the
event of loss-of-channel or low SNR ratio, the pilot
trip circuit is automatically locked out after a short
time delay. Pilot trip is provided, however, if the trip-
ping distance relay(s) operate(s) during this short
time period between loss-of-channel and pilot trip
lockout. ABB type TCF-10B receiver provides this
logic; it provides a 150 ms trip window, then auto-
matic lockout after loss-of-channel. Provision for a
second high-speed pilot trip is provided, for the situ-
ation when a permanent fault causes a permanent