Vacon OPTAF, User Manual

Page: 24 / 50

vacon • 22 STO AND SS1 SAFETY FUNCTIONS
Local contacts: https://www.danfoss.com/en/contact-us/contacts-list/
* See Chapter 3.5.7.
Safe Stop (SS1) safety-related data
The SS1 safety function consists of two subsystems with different safety-related data.
The subsystem consisting of the time delayed safety relay is manufactured by PHOENIX CONTACT
and of type:
- PSR-SCP-24DC/ESD/5X1/1X2/300 or
- PSR-SPP-24DC/ESD/5X1/1X2/300
See manufacturer user manual (by ID "2981428 or "2981431") for more information regarding the
time delayed safety relay.
Subsystem
Safety Relay
Subsystem
NX STO
Safe Stop 1 (SS1) safety-related data:
- For combining the two subsystems, the maximum safety integrity level or performance level
reached is the lowest of a subsystem.
→
SIL 2 or PL d
- The PFH value for a safety function of combined subsystems is the sum of all subsystems
PFH values.
PFH
SS1
= PFH
Safety Relay
+ PFH
NX STO
= 1.89 x 10
-9
/hour + 2.70 x 10
-9
/hour = 4.59 x 10
-9
/hour
→
The result is within the requirements for SIL 2 or PL d (PFH is even within the requirements
for up to SIL 3/PL e).
IEC 61508:2000
Low Demand Mode SIL 2
PFD
avg
= 2.61 x 10
-4
T
M
= 20 years
Dual Channel Structure
SIL 3
PFD
avg
= 2.30 x 10
-4
T
M
= 20 years
Dual Channel Structure
SIL 3
PFD
avg
= 2.9 x 10
-4
T
M
= 20 years
Dual Channel Structure
PSR-SC/PP-24DC/ESD/5X1/1X2 300 safety-
related data from user manual and certifi-
cate:
VACON
®
NX STO safety-related data:
IEC 61 508 SIL 2 EN 61800-5-2:2007 SIL 3
EN 62061 SIL CL 2 EN 62061:2005 SIL CL 3
DIN EN/ISO 13849-1
PL d
Category 3
+
IEC 61508:2000 SIL 3
PFH
1.89 x 10
-9
/hour
DIN EN/ISO 13849-
1:2006 PL e
Category 3
PFH
2.70 x 10
-9
/hour
EN 61800-5-2:2007 SIL 2
EN 62061:2005 SIL CL 3
→
IEC 61508:2000 SIL 2
DIN EN/ISO 13849-1:2006
PL d
Category 3
PFH
4.59 x 10
-9
/hour