You should test before installing - I've found that sometimes power isn't necessary on the local end, but only on short (100ft) runs. More importantly, if you aren't sending true RS-232 - for example, using an Extron device - you need to build a custom DB9 shell for the local extender and short out pins 6 and 7 to complete handshaking. Documentation is very weak you're literally using 2 black boxes here. Otherwise this is a good product, and significantly cheaper than other extenders.
My task was to get an old Feed Grinder's COM/Serial/DB9 PORT on a hog farm to once again communicate with a computer in the farm's office more than 400 feet away. Previously, a old baud modem was used via phone line run in buried conduit, but that stopped working. Initially, I tried a tiny dell optiplex (with a COM PORT in the back) and wireless internet blasted the distance (and rerouted). It was NOT reliable and the heat was too much on the tiny Dell in a FG Cabinet.
So, I pulled the PC out once I found a StarTech RS-232 "SERIAL TO IP" Device Server. I thought this would solve all my problems. I tied Cat5e to that buried phone line and pulled it through. Crimped the ends and thought all was well, but it didn't work. In my haste, I didn't learn that the upper limit of ethernet data was 100m. The computer / router simply couldn't communicate with the FG. It was too far away.
As I was researching options to fix this, POE Injectors, ethernet extenders (would have to be installed somewhere in the middle if I dug it all up), or even Coax Cable/Phone Line solutions, I found this RS232 Extender. Exactly what I needed the WHOLE DARN TIME. Since it is not sending internet protocol, just the COM Data via a powered extender, it can go thousands of feet.
However, it did not work right off the bat. I don't know why either. It was odd. The FG Program simply wasn't seeing the device. (Though the Ethernet Cable tested fine). I tried this and that. I made sure the Device was mapped correctly (to COM1 via Device Manager and that the Program was searching COM1).
Ultimately, I did two things. Either one, or a combination of both, made it work. I slowed down the transmit and receive buffer one "click" each. I also opened up a port on Windows Firewall. I didn't realize it would ever use an actual port, but it was worth a shot! The port in question was 4660. Maybe that did nothing, and I'm stupid. Maybe it was exactly what I needed. Regardless, after 3 months and $500, this project is completed. IT WORKS! And, with TeamViewer or another Remote Desktop Application, this Feed Grinder can now be operated from anywhere in the world. And for that, I thank you!
PROS: Cost Effective, Small Size for tight spaces
CONS: Manual leaves a much to be desired, but the web is a GREAT resource for these oddball things days. Needs to come with some GENDER CHANGES just in case! I needed them (and ordered them but they didn't arrive) and had to MAKE them with what I had. I also wish it had a little green light on it just to let you know it was ON. There's no way to know it's working!
Worked as the description said it would. Was able to extend a serial connection for a master radio over cat6 to a computer in another building. Works great and has a small foot print. Wish it came with 2 of the little serial cable pigtails instead of just one.
Failed to communicate with my device. I tried multiple configurations with no luck. Not the first such device I have used. Higher priced unit still in place on a phone system we installed to program remotely. I will do more testing at a later date, in the meanwhile we rewired with a standard DB9 50 foot cable, and communicated perfectly first try.
PROS: Small - would be perfect for many of my needs - if it in fact worked.