Siemens SIMOCODE pro C System Manual page 48

Overview of functions
5.1 Protection functions
Dry-running protection for centrifugal pumps
The following high performance devices with PTB 18 ATEX 5003 X can be used to
implement dry-running protection of centrifugal pumps (non-electrical devices) through active
power monitoring and motor shutdown:
● SIMOCODE pro V PB from version *E16*
● SIMOCODE pro V PN from version *E13*
● SIMOCODE pro V EIP from version *E04*
This applies to centrifugal pumps with progressive flow characteristics, which are also
suitable for pumping flammable media and are also installed in hazardous areas.
Installation in potentially explosive atmospheres
SIMOCODE pro itself is not suitable for installation in potentially explosive atmospheres!
If the active power, and thus the flow rate, falls below a minimum value, the motor - and thus
the centrifugal pump - is switched off The devices support monitoring of the minimum flow
rate for a freely selectable minimum value. A delay time (effective during operation including
the pump's regular switch-off) can be specified to minimize the probability of incorrect
tripping in addition to the parameter for the trip level of the minimum active power (which
corresponds to a minimum flow rate). During the start-up procedure, operation with active
power below the trip level can constitute a regular operating status of short duration
(depending on the procedure used to open the pressure-side shut-off valve). For this reason,
a start-up bridging time can be specified to prevent incorrect tripping during the start-up
procedure.
The parameters can be entered using the "SIMOCODE ES" (TIA Portal) engineering
software.
It is also possible to determine the trip level in a "teach-in" and to enter the further
parameters with the aid of menu-guided input screens. Using this method, the operating
point with optimum flow rate and the point with minimum flow rate are started up with real
operating medium, as a result of which the trip level of the minimum active power is
determined. The teach-in has to be repeated following any changes in the pump or system
characteristics (e.g. as a result of changing the operating medium or of intervention in the
plant configuration).
With regard to dry-running protection for centrifugal pumps, a current/voltage measuring
module especially intended for this function is also required in addition to the basic unit.
See also:
● Chapter "Dry-running protection for centrifugal pumps by active power monitoring
(Page 314)" in the safety and commissioning information for Ex areas
● Chapter "Dry-running protection for centrifugal pumps" in the manual Parameterizing
SIMOCODE pro (https://support.industry.siemens.com/cs/ww/en/view/109743958).
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WARNING
System Manual, 05/2019, A5E40507475002A/RS-AD/004
SIMOCODE pro