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| - | Some rules on how to design a CAN network. Consider reading [[Problem Solving Questions]]. | ||
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| - | The rules are general and valid for an CAN network including [[CAN Higher Layer Protocols: | ||
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| - | * Always use twisted pairs for CAN_H and CAN_L. | ||
| - | * Several manufacturers offer also four twisted cables for CAN when using 4-wire construction. This makes cable thinner and enables moulding of 2x2x0.5mm2 into e.g. M12-connectors | ||
| - | * Maximum cable length is between the two farthermost nodes on the CAN bus line. Remember, in the worst case a signal has to travel from the node at one end to the node on the other and of the line. It is a function of the bit rate as follows: | ||
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| - | |bit rate|max cable length (in m)| | ||
| - | | 1Mbit/ | ||
| - | | 800Kbit/ | ||
| - | | 500Kbit/ | ||
| - | | 250Kbit/ | ||
| - | | 125Kbit/ | ||
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| - | (Table from CiA DS 301 4.02 page 20) \\ | ||
| - | CiA 303 Part 1: Cabling and connector pin assignment has recommendations for connectors and cables used in CANopen systems. | ||
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| - | If you ask for a formula? There is one rule of thumb: | ||
| - | cable length < 40000 Kbit/s * 1 m / BitRate in Kbit/s | ||
| - | BitRate given in Kbit/s as well. Using this, results in < 40m for 1Mbit/s or | ||
| - | < 320m for 125Kbit/s. In this formula a typical transceiver propagation of 25ns and a typical cable propagation of 5 ns/m is used for calculation. | ||
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| - | [[http:// | ||
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| - | ==== CAN cable types ==== | ||
| - | All big vendors have specialized CAN cables, but they are not necessary called **CAN** something | ||
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| - | * [[http:// | ||
| - | * [[http:// | ||
| - | * [[http:// | ||
| - | * [[http:// | ||
| - | * [[http:// | ||
| - | * [[http:// | ||
| - | * [[http:// | ||
