Ol' timer AB people - using a SC to comm DH+

Hi all

I have a SLC500 5/04 and a PV+600 with a DH+ module. SLC is located at a lower level to where the PV+ and the machine it controls are.

In order to go online from the top level I have installed a 1770 station connector box with a serial 9 pin shell wired to the DH+. Using a PCM5 cable I should be able to detect the SLC but I have been unable to. Rockwell support tells me I have to have a station connector for each device in order to use one with a serial connection modified to it to detect the SLC & PV+.

Does this sound right to you guys? I dont want to shell out the cash if it doesnt work. I dont see how a dropline to each is different than just connection on one bus type setup. The only extra in 1770 SC is capacitor that is linked to the screen.

Thanks

TFC

Hi

Station connectors are, IMO a waste of money (130 GBP in UK). I've worked on systems both with and without station connectors. I've also worked on systems with DH+ problems that could not be solved by adding station connectors.

On a recent system we installed, the client insisted on us installing them because they had heard of running into problems by not using them.

Proper wiring of the DH+ network is much more important - correct cable, cable routing, terminating resistors, etc.

On short runs, terminating resistors may also cause more problems than they are supposed to solve.

Has anyone on the site actually used the 9 pin Dshell on a SC to get onto a DH+ network?

Ah oh, if Ken Roach or cousin Phillip from NZ havent replied looks like I could be back to the drawing board on this one

There are third party manufacturers of "convience ports" that allow connecting a PCM5 cable to DH+ network.

Phoenix Contact

Grace Engineering

I'm sure there are more. McNaughton McKay, a AB distributor, has a line also but I haven't found it online.

Hi

Yes, you can use a 9 pin D connector, I have used such a setup.
The 1770-SC installation manual only shows connection to a 15 pin D connector, so I'm not sure of the pinouts for the 9 pin.

You will still need to connect your PC using DH+ either through a PC card or KF2, etc. Serial RS232 will not work.

Hi Keith

I am using a PCMK card and the PCM5 cable (PCMK to 9 pin D shell)

On the 9 pin shell wired to the station connector, pin 5 is blue and pin 1 is the clear as per tech note G15996 or

http://domino.automation.rockwell.com/applications/kb/RAKB.nsf/0/8488DB9D37CFBD8185256AFB00639165?OpenDocument

I agree, this should work!

Have you verified the blue hose connection at the SLC and PV? I often find that the electricians installing the cable have reversed the clear and blue connections as if they were installing remote I/O. you have to reverse them for DH+.

Hi jstolaruk

Yes, the wiring for the PV+ is fine. The SLC to PV+ network has been in service for three months now. The new addition is the SC. I did try reversing the clear and blue connections but no good. I took the PV+ out of the circuit and used that good known network to the SC and still no good.

Best Regards

TFC

This is really obvious but have you tried different DH+ baud rate settings?

No.

Speed is set at 57.6K

How slow should you go?

TimeFluxCap said:

No.

Speed is set at 57.6K

How slow should you go?

Click to expand...

There are two possible settings, the other being 230K. I was just wondering if you had tried both. I believe you can lookup the speed through the setup config on the PV.