Lieu, Main features of devicenet, Main features of the—dgfc – GE Industrial Solutions OKCV3000CN DeviceNet User Manual

Page 9

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DeviceNet

1.4. MAIN FEATURES OF DEVICENET

These are the main features of DeviceNet:

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upto64nodes;

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3 selectable baud rates: 500, 250 and 125 kbaud;

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linear topology;

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distances between first and last node:

500 meters (1640 ft.) @ 125 kbaud

250 meters (820 ft.) @ 250 kbaud

100 meters (328 ft.) @ 500 kbaud

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duplicate MACID detection;

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trunk/drop line cable;

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trunk line is the backbone (main line) of the cable system;

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drop line is the cable that “hangs” from the trunk line and connects devices to the trunk line;

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maximum drop line length is 6 meters;

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cumulative drop line length is:

156 meters (512 ft.) @ 125 kbaud

78 meters (256 ft.) @ 250 kbaud

39 meters (128 ft.) @ 500 kbaud

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trunk line is terminated by 120-ohms resistors on both ends;

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shielded double twisted pair (power +signal);

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cable is 5 wires: 2 for power, 2 for signal, 1 for shield

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miswiring protection;

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multimaster capabilities;

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peer-to-peer;

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node removal without severing the network;

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CAN technology (built-in error management as CRC, stuff, form, etc. and Bus Off);

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supports isolated and non-isolated nodes;

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supports self-powered and network-powered nodes (simultaneously);

1.5. MAIN FEATURES OF THE—DGFC

These are the main DGFC DeviceNet features.

1

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support of the Predefined Master/slave connection set. This allows the exchange up to 10 drive param-
eters in reading and 10 in writing with the master (usually a PLC, but a PC card can also be connected). In
this case the card is slave only. There are two sub-modes. The first is to use a DGFC as a communication
only card, the second to use aDGFC as a communication card and execute aBricks program simultaneously.

2

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support of a LocalBus. By using some DeviceNet Bricks (or W-f-D blocks) you can connect a DGFC to
another DGFC (peer-to-peer), without using any other node (no PLC/PC required). Note that each node can
have up to 3 masters and many slaves at the same time.

LiEU

INTRODUCTION

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