Siemens GMSG-GCB Instruction Manual page 45

Note: Right-hand vertical segment of curve is located at the maximum symmetrical interrupting current rating of the circuit breaker, as
indicated in Table 3: Typical vacuum interrupter contact life and stroke on page 44.
Permissible operating cycles
100,000
50,000
20,000
10,000
5,000
2,000
1,000
500
200
100
50
20
10
1 2 5 10
Breaking current (symmetrical value)
Figure 37: Typical vacuum interrupter contact life curves
Load graph "A" vacuum interrupter type VS-17006
18 50
20 2325
100
45