Profibus

Fritz_frederix

Member

Join Date

Apr 2003

Location

Belgium

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434

• Jun 18, 2009

• #1

Hi Folks,

We've got a profibus single loop starting from our profibus card (Delta-V) and ends a few 100 m futher with a the end resisitor on. Do we need to put the resistor at the beginning (delta-v card) on?

Thx

 

JesperMP

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Feb 2003

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ᚴᚬᛒᛅᚾᚼᚬᚠᚾ

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16,361

• Jun 18, 2009

• #2

Yes. The termination must always be on in the extreme ends of the daisy-chained cable. It is irrelevant what the cable is connected to. It is the question if the cable is at a physical end or not.

 

TurpoUrpo

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T

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May 2008

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Switzerland

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1,571

• Jun 18, 2009

• #3

Yes, profibus needs active termination at both ends.

 

Fritz_frederix

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OP

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Apr 2003

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Belgium

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434

• Jun 18, 2009

• #4

Thx guys

 

GeorgeB-J

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G

Join Date

Feb 2009

Location

Llangollen

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8

• Jun 18, 2009

• #5

Whatch out there is a maximum lenghth for Profibus segments if you have " a few 100M " then you will require repeaters in the network!

 

SteveMaves

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S

Join Date

Apr 2009

Location

Minneapolis, MN

Posts

141

• Jun 18, 2009

• #6

Terminator may be built into DeltaV Card

Some profibus scanner cards have an internal terminating resistor built into them. I don't know if the DeltaV has one or not, but you should check on that.