i have a device which works on RS 422 four wire , but does not have any identity of its own ( means there is no option for putting any address ). i need to connect 88 devices on a single system, how can i do this ?

 

i have a device which works on RS 422 four wire , but does not have any identity of its own ( means there is no option for putting any address ). i need to connect 88 devices on a single system, how can i do this ?

Oem/vendor type model of the devices...

 

It's not working by this way here..you post is just like " incomplete" No infos/datas..

 

With RS-422 four wire you can only connect 2 devices to each other. So there is never a need to set an address - you always know whom you are talking to (= the other).
Now it could be that the vendor says "RS-422 four wire" but actually means: RS-485 four wire. In this case, the device being the master also doesn't need an address. Like in Modbus.
BTW, with RS-485 the normal max device limit per cable segment is 32. You need repeaters to reach 88.

 

With RS-422 four wire you can only connect 2 devices to each other. So there is never a need to set an address - you always know whom you are talking to (= the other).
Now it could be that the vendor says "RS-422 four wire" but actually means: RS-485 four wire. In this case, the device being the master also doesn't need an address. Like in Modbus.
BTW, with RS-485 the normal max device limit per cable segment is 32. You need repeaters to reach 88.

Original poster even gave a quick reply update... So bye bye

 

RS-422 is the long-distance version of RS-232, both of which are point-to-point hardware layers, so devices using 232 or 422 are not expected to be addressable.

Either of my approaches involves a gateway or a converter at each device to establish addressability:

1. If whatever master is involved can talk over an Ethernet port, then use the IP address of a Ethernet/RS-422 converter at each node to get addressability of each field device. An Ethernet topology might offer more freedom with its hub and spoke cabling, compared to RS-485 with its daisy chain cabling. Depends on your geographical layout.

2. There's a gateway product that might be programmable to the extent that its fieldbus side could be 'addressable' and the device side being RS-422 point-to-point to your field device so that the gateway takes on the addressing function. I'm speculating from the web page description:

Unigate CL RS232 / 422 / 485 Gateway

RS232/422/485 enable any RS232/485/422 serial or Modbus device with the UNIGATE CL Gateway. Make any serial device a RS232/422/485 Master/Slave using the UNIGATE CL Gateway. Its low-cost and flexibility are ideal for high volume applications. One side of the gateway is a fieldbus, RS232/422/485 Master/Slave, while the other side is a high performance serial port that directly interfaces with your serial device. The serial side of the UNIGATE can either be used in one of many standard configurations (including Modbus RTU master/Master/Slave and standard RS232/422/485), or can be customized with its built-in scripting language. Volume and OEM pricing available.

CUSTOM PROTOCOLS:
The UNIGATE CL Gateway allows for the quick development of custom applications on the serial side using its powerful scripting language. When developing a custom application, or for simple configuration to a standard protocol, we recommend using a Starter Kit. Starter kits contain all the connection cables and power supplies for configuring and/or scripting. There is even a RS232/422/485. Scripts are written using the Protocol Developer Tool. If you need a custom protocol and scripting is not for you, Grid Connect offers scripting services at reasonable rates (call for details).

https://www.gridconnect.com/products/unigate-cl-rs232-422-485-gateway

If there's one like this, there might be others.