ABB ACS880-17, User Manual

Page: 53 / 58

Technical data 53

Safety component types
Safety component types as defined in IEC 61508-2:
•
FSO module: type B
•
FSE module: type B
•
emergency stop button: type A
•
drive STO circuit:
•
frame sizes R1...R9 and drives with R1i...R7i inverter modules: type A
•
frame sizes R10 and R11 and drives with R8i inverter modules: type B.

Safety block diagram
The components that are included in the safety circuit are shown in the safety block
diagram below.

Relevant failure modes, diagnostics
Relevant failure modes are:
•
the FSO module detects any open circuits and short circuits and redundancy failures
of the emergency stop input signal wirings. Similarly, it detects redundancy failures of
the emergency stop button when the request is on.
•
internal failures of the emergency stop button, the FSO and FSE modules and the
STO function in the drive.
These failures are included in the failure rate value of the function.

Fault exclusions
Fault exclusions (not considered in the calculations):
•
any short and open circuits in the cables of the safety circuit inside the cabinet
•
any short and open circuits in the cabinet terminal blocks of the safety circuits.

Operation delays
Emergency stop total delay and fault reaction response time (includes the response time
of the drive STO):
•
Stop category 0: less than 100 ms
•
Stop category 1: Emergency stop ramp time + possible STO delay se
(<100 ms).
Note : When you define the total response time for the safety function and the fault reaction
function, you must add the delays of the safety pulse encoder (if used).
E-stop
button
FSO
module,
FSE
module
(if used)
Drive
module
(STO)