Siemens SINAMICS S120 Function Manual page 418

Basic functions
7.26 Extended service mode for CU310-2 connected to blocksize power units
Activating/deactivating the essential service mode
Signal p3880 = 1 activates the essential service mode:
● If the motor was switched off by activating essential service mode, the converter switches
the motor on.
● If the motor was switched on by activating essential service mode, the converter switches
the speed setpoint to "ESM setpoint source".
Signal p3880 = 0 deactivates the essential service mode:
● If one of the OFF1, OFF2 or OFF3 commands is active, the converter switches off the
motor.
● If neither OFF1, OFF2 nor OFF3 is active, the converter switches the speed setpoint from
the "ESM setpoint source" to the normal setpoint source.
Special features of the essential service mode
Use other signals to switch on and switch off the motor when the essential service mode is
active
The OFF1, OFF2 and OFF3 commands for switching off the motor have no effect.
The converter blocks all functions that switch off the motor to save energy, e.g.
PROFIenergy or hibernation mode.
Unexpected exiting of the essential service mode by selecting "Safe Torque Off"
PM240-2 Power Modules have terminals to select the "Safe Torque Off" (STO) safety
function. An active STO function switches the motor off, thus terminating the essential
service mode. The termination of essential service mode can cause severe injury or death,
e.g. as smoke and associated gases are no longer extracted.
• Set both STO switches to the "OFF" position on the PM240-2 Power Modules.
Response to faults when the essential service mode is active
In the "essential service mode", the converter does not switch off the motor when faults
develop, but instead responds differently depending on the fault type:
● The converter ignores faults, which do not directly result in the destruction of the
converter or the motor.
● The converter attempts to automatically acknowledge faults, which cannot be ignored,
using the automatic restart function.
● For faults that cannot be acknowledged, it is possible to switch over the motor to line
operation using the bypass function.
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WARNING
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
Drive functions