Typical system example – Rockwell Automation 294D ArmorStart LT Distributed Motor Controller DeviceNet Version - User Manual User Manual
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Rockwell Automation Publication 290D-UM001A-EN-P - June 2012
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Installation and Wiring
Chapter 2
Typical System Example
The primary function of ArmorStart LT is to control and protect a three-phase
squirrel cage induction motor. Three-phase power enters through terminals that
are connected to a manually operated disconnect switch. The three-phase power
may also connect internally to an optional three-phase to 24V DC power supply
(IPS). Wired in series with the disconnect is an electrically operated contactor or
a variable frequency drive. For Bulletin 294D an optional source brake contactor
may also be connected to the disconnect output terminals. The source brake
contactor is used to control an electromechanical brake physically attached to the
motor. The microcontroller and interface circuits are contained in the ECM.
The ECM also houses 6 user configurable I/O points. These six I/O points are
used for system level control and are accessible via by the communication
network or DeviceLogix.
The user has the flexibility to coordinate the appropriate safety function for their
application. ArmorStart LT does not provide a safe torque-off input. Therefore,
the safety function is configured externally from the controller and based upon
the risk assessment.
For example, the risk assessment may require a safety circuit with a high level
of performance. In this example, a safety relay with redundant safety contactors
and emergency stop function can be integrated into the machine controls.
below is an example of this configuration. Contact your local
Rockwell Automation supplier for additional support regarding the safety
circuit or for a risk assessment of your machinery.
Figure 17 -