Siemens SINAMICS V20 Operating Manual page 10

Pump switch-in/switch-out
External control circuit
Pump switch-in
If the pump controlled by the inverter runs at the maximum speed (P1082) and the PID error
is higher than the switch-in threshold (P2373) and lower than the delay override threshold
(P2376) for a specified time (P2374), the inverter first switches the pump from inverter
operation to line system operation, and then switches on an idle pump which is softly started
with a ramp-up speed and runs in inverter operation.
Note
If the PID error rises above the switch-in delay override threshold (P2376), the inverter skips
the switch-in delay (P2374) and performs the switch-in operation immediately.
Parameter P4012 is used to control the selection mode of the next pump that is softly started
by the inverter. Bits 01 to 04 of r4000 control the pump which is selected to run depending
on P4012.
●
switches in the pump by following the sequence M1, M2, M3, to M4.
● P4012 = 1: Selecting the next pump according to the operating hours. The inverter
switches in the pump with the least absolute operating hours (r4026 to r4029).
10
P4012 = 0: Selecting the next pump according to the fixed sequence. The inverter
SINAMICS V20 multi-pump control
Operating Manual, 05/2018, A5E43416874-002