2.6
Determining the lifetime and validating the
entire system
The following steps are mandatory.
■
Determine the real parameters of the system.
4
Required performance level
4
d
op
4
h
op
4
t
cycle
■
The operator must verify that the lifetime T
M
is not exceeded.
■
Validate the entire system.
■
Observe the safety considerations in the operating instructions of the safety
relay.
2.7
Example calculation
The following values are only examples and must be replaced with your own
values.
■
Performance level e must be achieved.
■
d
op
= 250 d
■
h
op
= 24 h
■
t
cycle
= 10 s
n
op
[cycles / year]
n
op
= (d
op
* h
op
*3600 s) / t
cycle
n
op
= 250 d / y * 24 h / d * 3600 s / h / 10 s / cycle = 2,160,000 cycles / year
According to the operating instructions, the relay has a lifetime of approximately
20 million cycles before a dangerous failure can occur.
T
M
= 20,000,000 / n
op
T
M
= 20,000,000 / 2,160,000 = 9.3 years
According to this calculation, the relay has to be replaced after 9.3 years.
For other relays, values such as B
10D
or T
10D
can be specified. These values are
not considered here and can be requested from CAPTRON.
safeCAP SC30
Original operating
instructions
1.1
7/25
