3
03/2006
3.2 MPI network rules for SINUMERIK 810D
3-24
© Siemens AG 2006 All Rights Reserved
SINUMERIK 840D/810D Start-Up Guide (IADC) – 03/2006 Edition
3.2 MPI network rules for SINUMERIK 810D
Please take the following basic rules into account when undertaking network
installations:
1. The bus line must be terminated at both ends. To do this, activate the termi-
nating resistor in the MPI connector of the first and last node, and deactivate
the remaining terminating resistors.
Note
S Only two resistors are permissible.
S With HHU, bus terminating resistors are hard-wired into the device.
2. It is necessary to apply 5 V voltage to at least 1 terminator. This occurs auto-
matically when the MPI connector with active terminating resistor is connec-
ted to a live device.
3. Spur lines (lead cables from the bus segment to the node) should be as
short as possible.
Note
Any spur lines that are not assigned should be removed if possible.
4. Each MPI node must be connected before being activated. When discon-
necting an MPI node, the connection must be deactivated before the con-
nector can be pulled out.
5. You can either connect one HHU and one HT6, or two HHUs or HT6s per
bus segment. It is not permissible to connect bus terminators to the distribu-
tor boxes of an HHU or HT6.
If necessary, an intermediate repeater can be used to connect more than
one HHU/HT6 to a bus segment.
6. The following cable lengths for the standard MPI without repeater must not
be exceeded:
MPI (187.5 kBaud): max. total cable length 1000 m
Note
Piggy-back connectors are not recommended for power connections.
3 Settin
s, MPI/BTSS
To Next Page
Loading...
