DeviceNet noob

OK I am laying out my first DNet system. I have 4 nodes within about 25' of each other. The nodes are robots. The controls for the robots are 480v so I have to have 600v rated cable.
The load on the cable will be 240ma plus whatever the 1769-SDN draws. So I was thinking of using thin cable because of it's flexibility. I am running into problems getting the cable. I can get the cable from my distributor the first week of May. The system has to be running the 2nd week in April. So anybody a source for cable or a better idea.
I plan on daisychaining the nodes.

Next problem I have only read about this problem for guys like Ken Roach. How do I leave a access port for the Guy that comes behind me to service this system? I have only ever used the passthru driver in RSLinx.

Why leave an access port? Just attach to the processor through Ethernet and then you can do anything you need to do with DN.

If you have to do any hardcore DeviceNet troubleshooting you need a port onto the network. I have a DeviceNet Detective and Netmeter so I would need 2 access ports.

Most of the thin cables I've seen are 300V rated jackets; if you're looking for a small quantity of 600V rated thin cable that might explain the long lead time. Make sure you're asking for Belden cables, not just the A-B part number.

I really like the PowerTap and related DeviceBox junction boxes for using thick (600V rated) DeviceNet trunk cable. The spring loaded terminals inside are very vibration resistant and if you do even the most cursory job with the gland nut it stays waterproof. That being said I've seen countless inventive ways to leave out grommets, leave off nuts, attempt to seal against wire instead of jacket, lose and strip screws, remove seals and if all else fails, simply submerge these boxes.

Grace Engineering has excellent panel-mount access ports for DeviceNet. Otherwise I just leave a sealed drop cable, and connect my Detective or NetMeter or -PCD to it.

Ken you have been around once or twice so. Do you know if Grace makes a combo DeviceNet /Ethernet port? I planned on having a Ethernet port so why not a DeviceNet also?

We've been struggling with cable availability also. Ended up going with Balluff mid-sized (verses thick) for the trunks and thin for the drops.

JeffKiper said:

Ken you have been around once or twice so. Do you know if Grace makes a combo DeviceNet /Ethernet port? I planned on having a Ethernet port so why not a DeviceNet also?

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It isn't very often that you must tap into a DeviceNet network, so having port available on a Graceport seems a waste.

That, and AB does make spring-loaded tap connectors that plug into many of the AB DeviceNet connectors for configuring the network makes a dedicated port somewhat silly IMHO.

Just FYI

I did find a Grace port with both DeviceNet and Ethernet plus 120 VAC recepticle. not a bad price only around $250.

We use the 1788-EN2DN module to allow ethernet access to our devicenet networks. We just add one in the drive panel, and give it a node number, then patch with Cat5 to the nearest controls network switch.

We have some large networks with over 40 VFDs and all of them hanging off of SLCs, so the passthrough driver is not viable.

I don't know what the module costs, but I love having them if your plant has a controls lan...Then, you can RSNetworx and DriveTools right through RSLinxGateway to do all of your backup and restoring as well as troubleshooting at very good speeds.

This is a job for a old / new customer so I am going to over kill it just a little. The nodes are Robots. They don't allow any kind of pass thru programming. They sit there as dumb I/O on DNet.

I said over kill. I am going so far as to lay the system out so in a year or so when they want to divide up this work cell it can be done easily. Hopefully I will be the one doing that as well.