Siemens ecofast 3RK1702-2GB18-0AA1 Manual page 103

2.7.2 Behavior in the event of a power failure
24 V DC voltage supply (AS-i) non-switched (yellow AS-i cable)
This voltage is constantly available. It is required for:
• supplying the electronics in the motor starter
• interrogating the auxiliary contacts
The voltage is not disconnected in the event of an emergency stop or safety
shutdown.
Behavior in the event of undervoltage
• In the event of prolonged undervoltage or power failure > 20 ms the swit-
ching elements and the brake output are disconnected.
• When the supply is restored, the disconnection command and the associated
signal bits and error bits are acknowledged automatically.
24 V DC voltage supply (AUX PWR) switched (black AS-i cable)
This voltage is not constantly available. It is only required for:
• driving the switching elements, e.g. a contactor
The voltage can be disconnected in the event of an emergency stop or
safety shutdown (category 1 according to EN 954-1), so that all switching
elements are safely disconnected with the connected motors.
Behavior in the event of undervoltage
• In the event of prolonged undervoltage or power failure > 20 ms the swit-
ching elements and the brake output are disconnected.
• When the supply is restored, the disconnection command and the associated
signal bits and error bits are acknowledged automatically.
ECOFAST Motor Starters
GWA 4NEB 950 5221-12 DS 02
Wiring and interfaces
and power failure:
(24 V DC < 18.5 V)
and power failure:
(24 V DC < 18.5 V)
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