Warning Against Unintended Start; Ethercat - Danfoss MCA 124 Operating Instructions Manual

Safety
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1.1.4 Warning against Unintended Start

1. The motor can be brought to a stop with bus
commands while the frequency converter is
connected to mains. If personal safety consider-
ations make it necessary to ensure that no
unintended start occurs, these stop functions are
not sufficient.
2. While parameters are being changed, there is a
risk that motor starts.
3. A motor that has been stopped can 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.
WARNING
ELECTRICAL HAZARD
Touching the electrical parts may be fatal - even after the
equipment has been disconnected from mains.

1.2 EtherCAT

EtherCAT is a Ethernet based realtime communication,
which allows a master to communicate to slave in a
interval down to 30 microseconds. The size of the network
is almost unlimited since up to 65535 devices can be
connected. These factors do make EtherCAT to one of the
fastest Ethernet based protocols in the marked.
The topology in EtherCAT can be made as line, tree or as
star. This gives the user the flexibility to route the cabling
in the most optimal way.
On the application level EtherCAT applies CANopen as the
application layer. This incorporates the usages of PDO
(Process data Objects) for control of the devices and SDO
(Service Data Objects) for acyclic access to parameters of
the devices.
More information on EtherCAT can be found on the
EtherCAT technology groups homepage: www.ethercat.org.
Illustration 1.1 EtherCAT
Technology, Licensed by Beckhoff Automation Gmbh, Germany
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MCA 124 EtherCAT Operating Instruction
®
® is Registered Trademark and Patented
MG92A302 - VLT
®
is a registered Danfoss trademark