How to Connect RS-485

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om_tech_support_JT
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How to Connect RS-485

Postby om_tech_support_JT » Mon Oct 24, 2011 3:20 pm

Q: In your CRK514-KP product manual (CRK series with built-in controller), you show your RS-485 communication connector pin-outs, but you don't show the pin-outs for the computer side. How do I connect your signals to my computer's RS-485 port? I have a DB9 port.

A: Connect our TR+ to your pin3, our TR- to your pin4, and our GND to your pin5. This is for half-duplex.

kevalvirani
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Joined: Fri May 04, 2012 6:48 am

Re: How to Connect RS-485

Postby kevalvirani » Fri May 04, 2012 6:56 am

Hi,
We had the same problem, We have CRD503-KP , and we tried connecting according to your instructions , but it was blinking C-ERR lights sometime and sometimes C-DAT was blinking. Even the C-ERR light was blinking in random manner. So can you suggest some troubleshooting procedure to connect it to the computer, we have standard RS 232 (COM) ports in our computer.
Is it necessary to connect both I/O ribbon and RS 485 connector to operate motors from computer ?
Please guide us, as we are not able to use driver we purchased recently.

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Re: How to Connect RS-485

Postby om_tech_support_JT » Fri May 04, 2012 4:11 pm

Hi,

Thank you for using our forum. I couldn't tell by your post, but do you have some type of signal converter between our CRD503-KP driver's RS485 port and your computer's RS232 port? Since an RS485 port is not common on PCs, a signal converter is required for the CRK series stored program type driver (built-in programmable controller) in order for it to communicate with the PC properly. We do not offer a converter as an accessory for the CRK driver because it's a common product that can be found easily in the open market.

We can provide some information about the converters we actually tested, but most should work fine. Please see below.

RS485 Converter v1 0.pdf
(189.75 KiB) Downloaded 347 times

kevalvirani
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Re: How to Connect RS-485

Postby kevalvirani » Wed May 09, 2012 6:38 am

Dear Sir,
Thanks for your reply, As per your suggestion we ordered below USB to RS485 Converter ,
http://www.rhydolabz.com/index.php?main ... cts_id=303

But Now the Software ("CRK Stored Program Controller Motion Creator") shows error "Serial Port Framing Error (Check Baud Rate or connection)".
We have tried all baud rates by selecting same rate on device as well as computer.

So can you guide me further ?

Regards,
Keval Virani

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Re: How to Connect RS-485

Postby om_tech_support_JT » Wed May 09, 2012 5:46 pm

Hi Keval,

Are you using the SAS or SACS command in your programs/sequences? If so, you can ignore this Serial Port Framing Error. If not, it may be caused by your converter. The Serial Port Framing Error points to incorrect baud rate setting or incorrect wiring. Other causes may be incorrect port, busy port, electrical noise, missing software driver (for converter), or mismatched baud rate setting between computer, converter, and CRD514-KP.

What were you exactly doing when this error occurred?

I have included some general set-up information below.

COMMUNICATION SET-UP:

CRK-KP uses standard RS485 half duplex communication.

A serial port is usually available on Desktop PC’s with a 9 pin D-sub connector, designated as COM 1 (and COM 2 if there are more than one COM port available). The user must provide converters for Serial or USB ports to RS-485.

The communication set up window always opens following the CRK-GUI software startup to allow user confirmation in selecting the Com port and baud rate before the port is actually opened. The default Com port and baud rate are stored from the previous settings. The communication set up can also be accessed at any time via the Set-Up pull down menu.

Communication settings:
Com port: Com1 through Com16, user selectable.
Baud Rate (bps): 9600, 19200, 38400, 57600, 115200 user selectable.
Data format: Asynchronous mode fixed at 8 data bit, no parity, 1 stop bit and no handshake.
Protocol: ASCII (TTY + CRLF)
See related link: Communication Specification

Notes for USB:
If your PC does not provide a physical serial port but a USB port is available, you will need to purchase a USB to Serial converter.

Before installing the USB to Serial converter:

- Start the CRK-GUI software then select a COM port from 1 to 4. Any COM port that can be opened successfully will not work with CRK-GUI software since there is no physical connection for that port. Please make a note of those ports and do not use them.

After installing the USB to Serial converter.

- Select a new COM port that can be opened with the converter installed, usually COM 4 or COM 5.

COMMUNICATION SPECIFICATIONS:
Electrical characteristic
In conformance with EIA-485

Use a twisted pair cable (TIA/EIA-568B CAT5e or higher is recommended) and keep the total wiring distance including extension to 50 m (164 ft.) or less.

Transmission mode
Half duplex

Baud rate
Selectable from 9600 bps, 19200 bps, 38400 bps, 57600 bps, 115200 bps

Physical layer
Asynchronous mode (8 bits, 1 stop bit, no parity)

Protocol
TTY (CR+LF)

Connection pattern
Up to 16 drivers can be connected to one programmable controller (master device).

kevalvirani
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Re: How to Connect RS-485

Postby kevalvirani » Thu May 10, 2012 5:28 am

One More Question,
Can I directly use I/O port with the RS-232 port for the communication with the driver instead of RS-485 controller ?

If yes can you give me wiring reference / diagram for interfacing I/O port & Computer ?

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Re: How to Connect RS-485

Postby om_tech_support_JT » Mon May 14, 2012 3:50 pm

Hi Keval,

As far as we know, there's no way to successfully communicate by connecting the RS485 port on our CRK+ driver into your computer's RS232 port directly without a converter.

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Re: How to Connect RS-485

Postby om_tech_support_JS » Mon Nov 28, 2016 12:17 pm

Hi next428,

When you said that you did the exact same thing, but did not succeed, were you attempting to connect to the RS-232 port on your computer, or were you following the Communication Setup?

In order to connect an RS-485 communication driver to the computer, you will need a conversion cable. We have tested the following product:
http://www.orientalmotor.com/products/p ... B_v1_0.pdf


If you are connected with a conversion cable already, then are you receiving any alarms on your driver?


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