Section 5: Control & Logic Functions; User Defined Logic; Undervoltage Auto Restart (Restoration Of Supply); Motor Start/Stop - Siemens 7SR105 Rho User Manual

Section 5: Control & Logic Functions
5.1

User Defined Logic

5.1.1

Undervoltage Auto Restart (Restoration of Supply)

As an example user defined logic can be used to provide an undervoltage auto-restart scheme.
Motors can be automatically re-started after a momentary power loss. When the control voltage drops below drop-
out voltage the contactors are de-energised. Timers can be initiated to restart the drive upon restoration of supply
voltage - if the control voltage is restored within the programmed restart time. For example logic can be
implemented to allow an auto-restart, delayed for up to 100s after supply loss for up to 10s.
The logic can be configured using Reylogic Express – refer to the Reydisp Manager User Manual.
5.2

Motor Start/Stop

The motor can be controlled from the relay fascia (control mode) using these settings. Note that the control mode
'motor stop' command is not suitable for use as an emergency stop e.g. an emergency stop requires immediate
access (not via menu structure) and the relay may not respond to key presses during archiving. Typically
separate motor control pushbuttons will be wired directly to the motor control device or to binary inputs of the
7SR105 and 7SR17.
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7SR105 Rho and 7SR17 Rho Applications Guide
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