Siemens SIMATIC ET 200SP Manual page 30

Product overview
3.6 Specifications for operating fail-safe motor starters
Bright and dark tests
With bright and dark tests, safety relays such as ET 200SP F-PM-E (6ES7136-6PA00-0BC0)
or SIRIUS 3SK check whether their safe outputs can still be activated and deactivated. The
bright and dark tests are run cyclically. The ET 200SP motor starter is intended for operation
with an F-PM-E or 3SK connected upstream and is adapted to the bright and dark test times
of these devices.
You can find more information on the operating principle and parameter assignment of bright
and dark tests in the respective device manual.
To avoid an unintentional response of the fail-safe motor starter during the bright and dark
test, these tests must not exceed a certain time. Due to component aging, the permissible
read-back time can also decrease throughout the motor starter's service life. The voltage of
the power supply unit also has an influence on the permissible read-back time. Increase the
power supply unit's output voltage to minimize the risk of incorrect deactivation during dark
tests.
By trial and error, set the read-back time as low as possible, but so high that the output
channel is not deactivated.
Inadvertent starting of the motor if the bright test lasts too long
The motor can start if the bright test lasts more than 10 ms. There is a risk of severe injury
or death. Material damage is also possible.
Make sure that the bright test lasts less than 10 ms on devices that are connected
upstream of the motor starter.
Power supply
In the case of a 24 V DC power supply, observe the following safety measures:
● Ensure safe electrical separation and separate routing of cables.
● Ensure increased insulation of the extra-low voltage (SELV/PELV) from circuits with
hazardous potentials in accordance with IEC 60364-4-41.
● Use a permissible SELV/PELV power supply unit, thus making sure that the voltage on
the infeed bus does not exceed the permissible maximum voltage, not even if the power
supply unit is defective.
● To deactivate safely via the power bus, use a suitable power supply in compliance with
the requirements of the safety classification used.
In UL systems (corner-grounded delta), the starter's 24 V supply must be SELV. PELV is not
permissible in UL systems.
30
WARNING
Motor starter (3RK1308-0**00-0CP0)
Manual, 12/2016, A5E34821005002A/RS-AB/002