CHAPTER 2: PRODUCT DESCRIPTION
2.4 Signal processing
2.4.1 UR signal processing
The UR series relays are microprocessor-based protective relays that are designed to measure power system conditions
directly via CT and PT inputs and via other sources of information, such as analog inputs, communications inputs and
contact inputs. The following figure shows the overall signal processing in URs.
An analog low pass anti-aliasing filter with a 3 dB corner frequency is set at 2.4 kHz and is used for current and voltage
analog filtering as well as signal conditioning. The same filtering is applied for phase, ground currents, phase-to-phase
(when applicable), and auxiliary voltages. The 2.4 kHz cut-off frequency applies to both 50 Hz and 60 Hz applications and
fixed in the hardware, and thus is not dependent on the system nominal frequency setting.
B90 LOW IMPEDANCE BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
UR
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- *
|
72
|
1550 nm, single-mode, Laser, 1 Channel
|
73
|
1550 nm, single-mode, Laser, 2 Channel
|
74
|
Channel 1 - RS422; Channel 2 - 1550 nm, single-mode, Laser
|
75
|
Channel 1 - G.703; Channel 2 - 1550 nm, single-mode Laser
|
76
|
IEEE C37.94, 820 nm, multimode, LED, 1 Channel
|
77
|
IEEE C37.94, 820 nm, multimode, LED, 2 Channels
|
7A
|
820 nm, multimode, LED, 1 Channel
|
7B
|
1300 nm, multimode, LED, 1 Channel
|
7C
|
1300 nm, single-mode, ELED, 1 Channel
|
7D
|
1300 nm, single-mode, Laser, 1 Channel
|
7E
|
Channel 1 - G.703; Channel 2 - 820 nm, multimode
|
7F
|
Channel 1 - G.703; Channel 2 - 1300 nm, multimode
|
7G
|
Channel 1 - G.703; Channel 2 - 1300 nm, single-mode ELED
|
7H
|
820 nm, multimode, LED, 2 Channels
|
7I
|
1300 nm, multimode, LED, 2 Channels
|
7J
|
1300 nm, single-mode, ELED, 2 Channels
|
7K
|
1300 nm, single-mode, Laser, 2 Channels
|
7L
|
Channel 1 - RS422; Channel 2 - 820 nm, multimode, LED
|
7M
|
Channel 1 - RS422; Channel 2 - 1300 nm, multimode, LED
|
7N
|
Channel 1 - RS422; Channel 2 - 1300 nm, single-mode, ELED
|
7P
|
Channel 1 - RS422; Channel 2 - 1300 nm, single-mode, Laser
|
7Q
|
Channel 1 - G.703; Channel 2 - 1300 nm, single-mode Laser
|
7R
|
G.703, 1 Channel
|
7S
|
G.703, 2 Channels
|
7T
|
RS422, 1 Channel
|
7W
|
RS422, 2 Channels
SIGNAL PROCESSING
2
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