Reference 43
SM (SyncManager) synchronisation
• SM synchronisation can be used for all applications with less critical timing
requirements. Any network topology is converted into a daisy chain structure, so
even a star topology is logically a chain. This creates a network where the hop
delay is equal to the number of nodes * 500 ns. For example, a network with 30
slaves would have a delay of 15 µs between the first and last slaves. SM
synchronisation is supported because not all PLCs support DC synchronisation.
DC synchronisation requires the ability of the PLC to synchronise itself to the first
DC capable slave on the network. The drive supports a minimum synchronisation
period of 250 µs, or even multiples of 250 µs (500 µs, 1000 µs, 2000 µs, etc.) up
to 32 ms.
Setting the control reference source
The control reference source determines from where the drive receives enabling and
motion commands. The
CONTROLREFSOURCE
parameter must be changed to 1
(
_crsRT_ETHERNET_402
) to allow an EtherCAT master to control the drive, and to
prevent Mint updating the control word. Normally the master sets it due to a start-up
command in the installed ESI file, but there are other ways to set the control
reference source:
• Use an SDO write to object 0x5002.
• Set the
CONTROLREFSOURCE
to 1 (
_crsRT_ETHERNET_402
) using the
Parameters tool or Command window in Mint WorkBench.
• Set the
Control Ref. Source
item to 'RT Ethernet (CiA402)' on the Select
Operating Mode and Source page of the Mint WorkBench Operating Mode
Wizard.
See also
Setting the control reference source
on page
24
.
Resetting position
The actual position value is defined as read-only, so the only way to reset the position
of the drive over a fieldbus is to use the homing mode of operation:
• Change the operating mode of the drive to 'homing' by changing object 0x6060 to
'6'. To check that the drive has acknowledged the change of operating mode, read
object 0x6061 until it matches the value set in object 0x6060.
• Start the homing sequence by setting bit 4 in the control word object 0x6040.
• Wait for the
homing attained
or
homing error
bits 12 and 13 to be set in the status
word object 0x6041. This will indicate if the homing sequence completed
successfully or not.
If the homing sequence completed successfully, the actual position will have been
changed to the value of
HOMEOFFSET
. The default is 0.
Summary of Contents for MotiFlex e180
Page 1: ...ABB motion control Application guide MotiFlex e180 EtherCAT ...
Page 4: ......
Page 14: ...14 Safety ...
Page 20: ...20 Physical connection ...
Page 70: ...70 Reference ...
