Profibus Network Options

[automation89]

Hi All.

I have a question regarding the layout of a Profibus network.

I am using Simatic Manager step 7

The current layout is as follows ; there are two Norgren profibus nodes, the Norgren units only allow for one profibus cable entry per unit.

The current setup is a Profibus cable ran for each, from each remote panel back to the main PLC. Therefore there is two Profibus cables in the one plug.

This is working fine, but my problem is they now need to be moved to another PLC and to the end of this Profibus network.

What option do I have. Thanks in advance.

 

[sigmadelta]

Buy a Profibus repeater.

https://mall.industry.siemens.com/mall/en/WW/Catalog/Products/10008350

You can put the repeater between the PLC and one of your Norgrens, and on the other side of the repeater run cable to the other Norgren.

 

[automation89]

RS485 Repeater

Hi Sigmadelta

Thanks very much for that information. Below is the current set up.

If I use the repeater can I bring both Norgen nodes out of the repeater shown below. Does it act as splitter, in with the main Profibus network and out with two separate nodes. from the repeater. Have you used these before and are they reliable?

Kind Regards

 

[sigmadelta]

More precisely, what the repeater does is create a new Profibus segment. The repeater itself does not have a node address. So think more along the lines of your Norgrens being on one segment, and the rest of the network on another segment.

The repeater is mostly used to extend the distance of the Profibus network, but also to create a new segment when too many devices (32 devices is the absolute max, including the repeater) on one segment. But I have had to use it to make a T-branch or star-like cabling layout.

The repeaters are reliable, I've never used another brand other than Siemens.

But, are you sure there are not 2 Profibus connection points? I've never heard of a device not being able to connect in a daisy-chain fashion. What's the Norgren model number?

 

[Manglemender]

For devices that only have one connection point you can put two cables in to the same terminals: A with A, B with B and Screen with Screen. Anyone who has used older Eurotherm (SSD) drives on profibus did it that way.


Be careful with terminators. Each Segment must have a terminator at each end.

Nick

 

[automation89]

Hi Guys thanks a million. I have ordered the repeater going to go with this option.