Siemens SINAMICS PERFECT HARMONY GH180 Function Manual page 303

6. When the voltage achieves "Precharge voltage level" (2634) threshold, M2 is commanded to
open
– Event Log: "Precharge: Open M2",
–
– Even Log: "Precharge: Close M1"
– Once the contactor open is confirmed and transformer flux decays (half second timer),
7. Secondary M1 close command (CIMV), (DO-15 - J4-7,8,9, - CIMV for Gen4e precharge type
4) is iss ued and the state advances to "WAIT_FOR_M1_ACK".
– Event log: "Precharge: Waiting for M1 to close..."
8. While waiting for M1 to close (M1 ACK), PrechargeM1CloseAck_O, the excessive drive loss
decay curve is reset.
– Event Log: "M1 Closed - waiting for transformer voltage to rise"
– Also it allows 5 seconds for the fundamental input voltage to get to 80% before advancing
9. When the M1 contactor is confirmed closed and MV exists, cell diagnostics is enabled. This
sets the precharge complete.
– Event Log: "Precharge complete: No errors"
10.Once in the Precharge complete state is achieved, it will be maintained until reset in the fault
loop. The precharge state machine will no longer run or check for errors. The error checking
is turned over to the normal fault detection. The StartCellPrecharge_O signal should be
removed at this point.
11.If the CimvIsPulsed_O flag is true, the CIMV close command will drop out one second after
achieving MV. The actual relay will stay in until the MV contactor is tripped.
SOP flags used in Precharge:
• DriveReadyToPrecharge
• DriveReadyToPrecharge_I – flag that indicates all conditions are met for precharge to
commence
• PrechargeM1CloseAck_I – flag to indicate M1 status (true is closed)
• PrechargeM2CloseAck_I – flag to indicate M2 status (true is closed) CB2Status_O – flag to
indicate CB2 status (true is CB2 closed)
• CB2Status_O - flag to indicate CB2 status (true is CB2 closed)
• PCVMRStatus_O – flag to indicate CB2 voltage status (true is CB closed – no UV condition)
• TripPrechargeCB2_O – Command precharge CB2 to trip (set in SOP) – causes precharge fault
• MainInputVoltageDisable_O – flag to disable the M1 contactor (true is command to open)
• ClosedPrechargeCB_I – flag to trip the breaker (true is trip) – must connect to output
hardware
NXGPro+ Control Manual
Operating Manual, A5E50491925A
"PrechargeM2Close_I" is set false", and the state advances to "M2_OPEN".
M1 trip (TIMV) is commanded closed, a timer of 0.5 sec allows flux on the transformer to
decay, and then the state advances to M1_CLOSE.
to "PC_COMPLETE" and setting the "PrechargeComplete_I" flag, and precharge drive run
enable (PrechargeDriveEnable_I). If the 5 seconds times out, precharge is aborted with a
precharge fault.
Advanced Operating Functions
8.19 Pre-charge using Dedicated I/O
301