Siemens SIMOCODE pro System Manual page 678

Glossary
DP slave/DP standard slave
Earth-fault module (EM)
Earth-fault monitoring
Emergency start
Glossary-6
A slave which is operated on the PROFIBUS with the
PROFIBUS DP protocol and works according to the EN 50
170 standard, Volume 2, PROFIBUS.
The earth-fault module offers the option of implementing
powerful external earth-fault monitoring in connection with
the 3UL22 summation current transformer (making it
possible to evaluate rated fault currents of 0.3 A, 0.5 A and 1
A). In addition to the internal earth-fault monitoring function
which is supported by both device series, SIMOCODE pro V
can be extended by an additional and more precise external
earth-fault monitoring system.
SIMOCODE pro measures and monitors all three phase
currents. By evaluating the summation current of the three
current values, the motor feeder can be monitored for a
possible fault current or earth fault.
There is a difference between internal and external earth-fault
monitoring:
Internal earth-fault monitoring:
Internal earth-fault monitoring via current measuring modules
or current/voltage measuring modules is only possible for
motors with a 3-phase connection in networks that are either
grounded directly or with low impedance.
The basic unit uses the total current to detect a possible fault
current/earth-fault current.
External earth-fault monitoring with SIMOCODE pro V:
External earth-fault monitoring via a summation current
transformer and an earth-fault module is normally used for
networks that are grounded with high impedance.
The earth-fault module (EM) evaluates rated fault currents
using an externally connected summation current
transformer (e.g 3UL22).
Emergency start deletes the thermal memory from
SIMOCODE pro each time it is activated. This allows the
motor to be immediately restarted after an overload trip. This
function can be used to:
• Enable an immediate restart/reset after an overload trip
• Control the operation of the thermal memory (motor
model) during operation, if required.
Since the emergency start is edge-triggered, this function
cannot permanently affect the thermal motor model.
SIMOCODE pro
GWA 4NEB 631 6050-22 DS 03