Functionality - ABB AC500-S Safety User Manual

AC500-S Safety Modules
DI581-S digital safety input module > Functionality

3.3.2 Functionality

Digital inputs
LED displays
Internal power supply
External power supply
Self-tests and diagnostic functions (both start-up and runtime), like CPU and RAM tests, program flow con-
trol, cross-talk and stuck-at-1 tests, etc. are implemented in DI581-S according to IEC 61508 ed. 2 SIL 3
requirements.
DI581-S contains 16 safety digital input channels with the following features:
n Phase-shifted (unique) test pulses T0 ... T7 can be used for connection of mechanical sensors. Test
pulse outputs T0 ... T7 provide 24 V signal with a short phase-shifted unique pulses (0 V) of 1 ms. Since
the test pulses on each of the test pulse output channels are unique (due to the phase shift), they can be
used to monitor the cross-talk between the given input channel with connected test pulse output and
another wire, e.g, with 24 V DC, another test pulse output, etc. Test pulse outputs are dedicated ones:
– T0 can be used only with input channels I0 and I1
– T1 can be used only with input channels I2 and I3
– T2 can be used only with input channels I4 and I5
– T3 can be used only with input channels I6 and I7
– T4 can be used only with input channels I8 and I9
– T5 can be used only with input channels I10 and I11
– T6 can be used only with input channels I12 and I13
– T7 can be used only with input channels I14 and I15
n Input delay with the following values: 1 ms, 2 ms, 5 ms, 10 ms, 15 ms, 30 ms, 50 ms, 100 ms, 200 ms,
500 ms. Input delay value of 1 ms is the minimum one.
NOTICE!
The allowed signal frequency on safety digital inputs is dependent on the input delay value for the
given channel:
For channel input delay values of 1 ... 10 ms, the pulse length of input signal shall be ³ 15 ms
–
(~ 65 Hz) to avoid occasional input channel passivation.
For channel input delay of 15 ms, the pulse length of input signal shall be ³ 20 ms (~ 50 Hz) to
–
avoid occasional input channel passivation.
For channel input delay of 30 ms, the pulse length of input signal shall be ³ 40 ms (~ 25 Hz) to
–
avoid occasional input channel passivation.
For channel input delay of 50 ms, the pulse length of input signal shall be ³ 60 ms (~ 15 Hz) to
–
avoid occasional input channel passivation.
For channel input delay of 100 ms, the pulse length of input signal shall be ³ 120 ms (~ 8 Hz) to
–
avoid occasional input channel passivation.
For channel input delay of 200 ms, the pulse length of input signal shall be ³ 250 ms (~ 4 Hz) to
–
avoid occasional input channel passivation.
For channel input delay of 500 ms, the pulse length of input signal shall be ³ 600 ms (~ 1.5 Hz) to
–
avoid occasional input channel passivation.
76
16 (24 V DC)
for signal status, module errors, channel errors and supply voltage
through the expansion bus interface (I/O-Bus)
via the terminals ZP and UP (process voltage 24 V DC)
AC500-S 30.03.2017