Engineers often find themselves in a situation where there is not enough cable length for connecting end devices with RS-232, RS-422 and RS-485 interfaces to a computer or a controller. How to solve this problem? There are several options for extending RS-232, RS-422 and RS-485 interfaces!
Before we begin, let’s recall the maximum distance that data can be transmitted depending on the interface.
- RS-232 - up to 15 meters, point-to-point operation mode
- RS-422 and RS-485 - up to 1200 meters, point-to-point or multicast mode
Converting RS-232 to RS-422 or RS-485
The easiest way to extend the RS-232 interface is to use an RS-232 to RS-485 converter or an interface converter, which increases the distance from up to 15 meters all the way to up to 1200 meters. Think of I-7520 and TCC-100.
Although RS-422 and RS-485 interfaces are very similar, the RS-485 interface is much more common, we will use RS-485 as our example.
Extending RS-485 network through a repeater
If you are a few hundred meters short, there’s still a way to extend the RS-485 interface. For example, use a serial interface repeater or a hub.
The most basic repeaters are I-7510 and TCC-120, there’s also the I-7513 hub.
Extending RS-485 network through fiber optics
And what if you want to extend the RS-485 network for 2 kilometers and beyond?
To do this, we convert the serial interface to into fiber via the optic converter.
Consider the I-2541, TCF-90, TCF-142 and ICF-1150 models.
Extending RS-485 network via Ethernet
What if extension through fiber optics is too much effort, but you have a local Ethernet or Internet network?
You can use serial interfaces servers or converters from RS-232, RS-422 and RS-485 interfaces to Ethernet.
Consider the DS-700, iDS-700, tDS-700 and Nport-5000 series.
Extending RS-485 network via Wi-Fi
It is possible to connect the RS-485 interface to a Wi-Fi network.
RS-232/422/485 wireless device servers NPort IAW5000 and NPort W2000 series will come to your aid.
Extending RS-485 network via radio channel
If the Ethernet/Internet is not an option, consider the radio channel solution.
SST-900B by ICP DAS is the right tool for this job.
Extending RS-485 network via cellular modem
If the devices you are connecting are scattered across a vast and difficult terrain, you could use GSM or 3G cellular connection.
Consider the GTM-200 and OnCell G2100 series.
If you have any questions, please send an email at sales@ipc2u.com.
