Warning Against Unintended Start - Danfoss VLT MCA 121 EtherNet/IP Manual

1 Safety

1.1.4 Warning against Unintended Start

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1. The motor can be brought to a stop by means of digital commands, bus commands, references or a local stop, while the frequency converter
is connected to mains. If personal safety considerations make it necessary to ensure that no unintended start occurs, these stop functions are
not sufficient.
2. While parameters are being changed, the motor may start. Consequently, the [OFF] key must always be activated.
3. A motor that has been stopped may start if faults occur in the electronics of the frequency converter, or if a temporary overload or a fault in
the supply mains or the motor connection ceases.
Touching the electrical parts may be fatal - even after the equipment has been disconnected from mains.
Also make sure that other voltage inputs have been disconnected, such as external 24 V DC, load sharing (linkage of DC intermediate circuit), as well as
the motor connection for kinetic back up.
Please take note of discharge times and further safety guidelines from the section: "Safety and conformity", in the respective Design Guide (MG.33.Ax.yy).
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MCA 121 EtherNet/IP