ABB ACS880 Series, Application Manual, Page: 34 / 44

34 Technical data
Safety data

Drive/inverter module STO function
The drive/inverter module hardware manual contains the safety data for the internal Safe
torque off function (STO).

Drive/inverter module STO function and an FSO module
The table below lists the safety data for the Safe disconnection function, including the
safety data of the FSO module, the FSE-31 module (optional) and the safety data of worst
case ACS880 Safe torque off (STO). See the section
One-channel or two-channel
connection to an FSO module on page 19 .
Note :
•
The PFD values of the drive STO and the FSO and FSE-31 modules are based on T1
(proof test interval) of two or five years. The safety data and SIL capability are valid
only when proof testing is done with an interval of maximum two or five years.
•
The safety data in the table is valid only when parameter settings for the FSO digital
inputs are done according to section
FSO module on page 26 in chapter Parameter
settings .
•
The FSE-31 module is included in the calculations only if a safety encoder is used in
the application, the FSO-21 module is configured to activate the SS1 function (stop
category 1) in overtemperature situations and the ramp monitoring method is used in
the SS1 function.
•
The safety integrity of the protection function must be verified as required in
EN 50495. The SIL capability of the drive/inverter module internal STO and the FSO
and FSE-31 modules is up to SIL3 when parameter settings for the FSO digital inputs
are done according to section
FSO module on page 26 in chapter Parameter settings .
•
The PFD value defines the safety integrity for a low-demand application
(demand rate < 1/year) in respect to random failure rate.
•
The safety data below contains the failure rates (PFD) of the FSO and FSE-31
modules and the drive internal STO.
Safety data 1-channel digital input 2-channel digital input
SIL capability 3 3
PFH (1/h, T
1
=20a) 1.11E-08 1.06E-08
PFD (T
1
=2a) 2.58E-04 2.54E-04
PFD (T
1
=5a) 1.33E-04 1.21E-04
SFF (%) > 99 > 99
HFT 0 1
3AXD10000113948