Bus cable
To meet ISO 898, a bus cable with a characteristic impedance of 120
W
should be used.
The maximum usable cable length for reliable communication decreases with increasing
transmission speed. As a guide, you can use the following values which we have measu-
red, but they are not to be taken as assured limits.
General characteristic
Specification
Bit rates
125 kbit, 250 kbit, 500 kbit
Distance with larger
bus connections
500 meters at 125 kBaud
250 meters at 250 kBaud
100 meters at 500 kBaud
Number of nodes
64
Signal environment
CAN
Modulation
Basic bandwidth
Coupling medium
DC-coupled differential transmit/receive operation
Isolation
500 V (option: optocoupler on the transceiver's node side)
Typical differential input impe-
dance (recessive state)
Shunt C = 5pF
Shunt R = 25K
W
(power on)
Min. differential input impe-
dance (recessive state)
Shunt C = 24pF + 36 pF/m of the permanently
attached stub cable
Shunt R = 20K
W
Absolute max.
voltage range
-25 V to +18 V (CAN_H, CAN_L)
The voltages for CAN_H and CAN_L refer to the ground pin of the
transceiver. The voltage is higher than that on the V-terminal by
the amount of the forward voltage drop of the Schottky diode. This
voltage drop must be < 0.6V.
Grounding:
The DeviceNet network must only be grounded at one point, to avoid ground loops. The
circuitry for the physical layer in all devices are referenced to the V-bus signal. The
ground connection is made via the power supply for the bus system. The current flowing
between V- and ground must not flow through any device other than the power supply.
Bus topology:
The DeviceNet medium utilizes a linear bus topology. Termination resistors are required
at each end of the connecting cable. Stub cables are permitted up to a length of 6 meters,
so that at least one node can be connected.
Termination resistors:
DeviceNet requires a termination
at each end
of the connecting cable.
These resistors must meet the following requirements: 120
W
, 1% metal-film, 1/4 W
8
Expansion Card for S300/S600/S700
Expansion card -DeviceNet-
04/2012
Kollmorgen
ENGLISH
Содержание SERVOSTAR S300
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