Binary Inputs; Figure 2.8-1 Binary Input Logic - Siemens 7SR224 Description & Operation

(1) Description of Operation 7SR224
NB: The Relay has a flat frequency response measuring harmonic currents up to and including the
50th Harmonic but does not measure the content at the aliasing frequencies i.e. 800 Hz (16
harmonic) + 1600 Hz (32
2.8 B I
INARY NPUTS
The binary inputs are operated from a suitably rated dc supply.
Relays are fitted with 13, 33 or 43 binary inputs (BI) depending on the variant. The user can assign
any binary input to any of the available functions (INPUT CONFIG > INPUT MATRIX).
The Power Supply module includes the relay basic I/O incorporating 3 x BI and 6 x BO.
Pick-up (PU) and drop-off (DO) time delays are associated with each binary input. Where no pick-up
time delay has been applied the input may pick up due to induced ac voltage on the wiring
connections (e.g. cross site wiring). The default pick-up time of 20ms provides ac immunity. Each input
can be programmed independently.
Each input may be logically inverted to facilitate integration of the relay within the user scheme. When
inverted the relay indicates that the BI is energised when no d.c. is applied. Inversion occurs before
the PU & DO time delay, see fig. 2.8-1.
Each input may be mapped to any front Fascia indication LED and/or to any Binary output contact and
can also be used with the internal user programmable logic. This allows the relay to provide panel
indications and alarms.
Inverted Inputs
BI 1 inverted
Binary Input 1
INPUT
CONFIG>
BINARY
INPUT
CONFIG
BI n inverted
Binary Input n
Page 14 of 66
nd
harmonic) + 2400 Hz (48
BI 1 P/U Delay
=1
BI n P/U Delay
=1
Figure 2.8-1
th
harmonic).
BI 1 D/O Delay
BI 1
Event
BI n D/O Delay
BI n
Event
Binary Input Logic
©2009 Siemens Protection Devices Limited
th
INPUT CONFIG>
INPUT MATRIX
(Or gates)
Logic signals,
e.g. '51-1 Inhibit'