7 heartbeat telegram, 1 telegram structure, Heartbeat telegram – Lenze 931K User Manual
Page 47: Telegram structure, Canopen communication

CANopen communication
Heartbeat telegram
Telegram structure
l
47
KHB 13.0002−EN 4.1
5.7
Heartbeat telegram
The heartbeat telegram in implemented to monitor the communication between the drive
controller and the master. For this purpose, the controller cyclically sends messages to the
master. The master can check the cyclic transmission of these messages and initiate
corresponding measures if they are missing. The heartbeat telegram is sent with the
identifier 700
h
(1792
d
) + node address. It only contains 1 byte of user data and the NMT
state of the drive controller. The data length is 1.
In addition to the monitoring by the master, the bus system can be monitored by the drive
controller. For this purpose, the drive controller monitors the acknowledgement of the
heartbeat telegram. The absence of acknowledgements indicates that there is no other
active drive controller on the bus system or that the bus system is damaged by a cable
break.
The following response, which can be a warning, a quick stop or the immediate
disconnection of the power stage, can be defined in the error management.
5.7.1
Telegram structure
11 bits
4 bits
User data (1 byte)
1st byte
2nd byte
3rd byte
4th byte
5th byte
6th byte
7th byte
8th byte
Identifier
Data
length
N
)
Note!
If the acknowledgement of the heartbeat telegram is missing in the heartbeat
procedure, this can – depending on the error management settings – cause an
error. This error can only be acknowledged via DIN9 or the parameter setting
program (SDC) or a restart of the drive controller (for more detailed
information please refer to the software manual).