Danfoss VLT CDS 303 Operating Instructions Manual page 13

Safety Instructions and Gen...
(see Figure 2.7). Connecting inputs increases the probability
of a fault in the unsafe direction. A fault in one frequency
converter can result in all frequency converters becoming
enabled. The probability of a fault for T37 is so low, that
the resulting probability still meets the requirements for
SIL2.
1
12
37
Figure 2.4 STO Example
1 Frequency converter
2 [Reset] key
3 Safety relay
4 Emergency stop
Table 2.3 Legend to Figure 2.4
1
12
18
37
Figure 2.5 SS1 Example
MG34M422
Operating Instructions
1 Frequency converter
2 [Reset] key
3 Safety relay
4 Emergency stop
Table 2.4 Legend to Figure 2.5
2
3
4
Figure 2.6 STO Category 4 Example
1 Frequency converter
2 [Reset] key
3 Safety relay
2
4 Emergency stop
Table 2.5 Legend to Figure 2.6
3
4
Danfoss A/S © Rev. 2013-07-03 All rights reserved.
1
K 1
12
37
K 1
K 1
2 2
2
3
4
11