Binary (Digital) Inputs - Siemens 7SR224 Technical Manual

1.2.5 Binary (Digital) Inputs

Nominal
19 VDC
V
BI
88 VDC
1.2.5.1 Performance
Attribute
Maximum DC current for
operation
Reset/Operate voltage ratio
Typical response time
Typical response time when programmed to
energise an output relay contact
The binary inputs have a low minimum operate current and may be set for high speed operation. To achieve
immunity from AC interference, a BI pick-up delay of typically one-cycle can be applied. The default pick-up time
delay of 20ms will provide this immunity.
The standard EATS 48-4 specifies additional performance requirements to provide greater security against
external disturbances. This standard can be applied to applications where a binary input is used to influence a
control function (e.g. provide a tripping function) and the wiring is considered to be susceptible to capacitive
currents, but double pole switching is not applied. See Chapter 7 Applications Guide.
To comply with EATS 48-4, classes ESI 1 and ESI 2, external components / BI pick-up delays are required as
shown in fig. 1-1.
©2010 Siemens Protection Devices Limited
Operating Range
17 to 290 VDC
74 to 290 VDC
Value
V = 19 V 1.5mA
BI
V = 88 V 1.5mA
BI
≥ 90 %
< 7ms
< 20ms
7SR224 Argus Performance Specification
Chapter 3 Page 9 of 49