Eaton PowerXL DM1 Series, Руководство по установке, Страница: 95 / 102

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Appendix E—STO function
POWERXL SERIES VFDS
MN040060EN—September 2020 www.eaton.com
Appendix E—STO function
Description of safety function
Safety function and safe state
The safe torque off (STO) function of DM1 series AC drive is
implemented only by hardware and no software is involved
to perform the STO function.
The STO function is available for operator to turn off the
motor torque. It is intended to be used in the safety related
applications up to SIL 2 / SIL CL 2 acc. to IEC 61800-5-2, IEC
61508 and IEC 62061, and up to Cat. 3 / PL d acc. to ISO
13849-1.
Safety function
The power that can cause rotation (or motion in the case of
a linear motor) shall be switched off from the motor when
demanded.
Safe state
The safe state is when the power supply of the motor is
switched off.
System response time
The time from when the operator presses the emergency
stop button to when the motor power supply switch is
turned off is ≤ 1ms.
STO input signal requirement
The two STO inputs can not be exactly synchronized, STO
fault will not be triggered if the two STO inputs become
consistent within 200 ms.
Table 37. Safety-related parameters.
Operation mode FR1-4
Operation mode High demand
Safety integrity level SIL 2 / SIL CL 2
Systematic capability SC 2
Safety architecture 1oo1 and 1oo2 mixed
Category 3
Performance level d
System type B
HFT 1oo1 part 0
1oo2 part 1
SFF of each element 1oo1 part > 99%
1oo2 part > 60%
PFH 8.26E-10
PFD 6.76E-05
MTTFd 1041 years (high)
Proof Test Interval (PTI) 20 years
MRT 0 hour
MTTR 0 hour
(total failures) 598.30 FIT
S
(safe failures) 443.06 FIT
DD
(dangerous detected failures) 107.11 FIT
DU
(dangerous undetected failures) 54.93 FIT
ote: N 1 FIT = 10
-9
/h.
All the previously mentioned safety-related parameters are
calculated based on the assumptions:
•
Failure rate of each component is based on the Siemens
SN29500 database;
•
Component failure rates are constant over the life of
the device;
•
Operating at a maximum ambient temperature of 60°C;
•
The equal distribution is used for the failure modes ratio
of each component.
INFORMATION
The parameters mentioned above are calculated by Eaton
without considering failure rates of external devices e.g.
buttons, power supply, etc.
WARNING
The STO function shall be triggered at least once a year.