Manual
9 Additional Information
BU 0180 GB-0914 Pre-series version 169
9.5 Operation with FI circuit breakers
With frequency inverters (except 115V devices), leakage currents of up to 16mA are to be expected if the
mains filter is active. These are designed for operation with leakage current circuit breakers for the
protection of persons.
For further details, please refer to Section 2.7.4.
9.6 System bus
Frequency inverters and components communicate with each other via the system bus. This bus system is
a CAN bus with CANopen protocol. Up to four frequency inverters and their associated components (field
bus module, absolute encoder, I/O modules etc.) can be connected to the system bus. Integration of the
components into the system bus does not require any specific knowledge of the bus on the part of the user.
Only the proper physical configuration of the bus system and if necessary the correct addressing of the
participants need to be taken into account by the user.
The connection of the individual NORD components is described in this manual (See section 2.8, 3.3 and 3.4).
NOTE: Communication on the system bus only starts if an extension module is connected to the bus or if in
a Master / Slave system, the Master is parameterised to P503=3 and the Slave is parameterised to P503=2.
This is especially important if several frequency inverters which are connected via the system bus are to be
read out in parallel with the NORDCON parameterisation software. In this case, identification of the devices
with NORDCON is not possible.
Physical structure
Standard
CAN
Bus length
20m with a wire cross section of 0.25mm² (AWG23)
Structure
preferably linear
Spur cables
possible, (max. 6m)
Termination resistors
120Ω, 250mW at both ends of a system bus
(with SK 1x0E-… or SK xU4-… via DIP switches)
Baud rate
250kBaud - preset
SYSTEM BUS
Configuration Example
1. FI
2. FI
3. FI
4. FI
1. I/O
Extension
8. I/O
Extension
Field Bus
Option
additional participants
(I/O extensions, CANopen encoder
Note:
Terminal77 = System bus + (CAN H)
Terminal78 = System bus - (CAN L)
Terminal numbers may differ