Monitoring cable question

[herb]

Hello.
Could someone please help.
I want connect the RS232 DB9 port on my Samil inverter to a spare RJ45 port on my router.
Samil manual says, pin2 RxD, pin3 TxD, and pin 5 Ground, but I am not clear what pins to connect to on the RJ45 Plug.
I have seen a few diagrams on the internet but think they are for different applications as they are not all connected the same way, below is one example.

DB9 RJ45
2 RxD 3
3 TxD 2
5 Gnd 5

Does anyone know if this would work, if not any suggestions as to what pins on the RJ45 I should use.
I have also read that if it's wrong it won't damage anything, but simply won't work, however I don't know if that's true and don't want to risk any damage.
Thanks a lot.

 

[Worcester]

RS232 is serial comms, RJ45 is ethernet bit like plugging a gas cooker into the mains ....

You'll need something to communicate and collect data from the RS232, and then send the datat over ethernet sound like if you want to do that you've got a nice little Rasberry Pi project on your hands

 

[Meggerman]

RS232 is serial comms, RJ45 is ethernet bit like plugging a gas cooker into the mains ....

You'll need something to communicate and collect data from the RS232, and then send the datat over ethernet sound like if you want to do that you've got a nice little Rasberry Pi project on your hands

We do plug gas cookers in to the mains. They have timers and ignitions

 

[tazz]

The rs232 pins are correct if looking a the rear of the plug....but its anyones guess at what pins you need on the rj45

 

[Worcester]

What I was trying to say is they are different communications protocols. The RS232 is talking serial, (aka English) and the RJ45 is talking in TCP/IP (Double Dutch) joining them together with a bit of damp string (aka wire cable) is worse than putting an Englishman and a Pair of Identical Dutch Twins in a bar in Ibiza - Serious misunderstanding and nothing likely to come of it!

 

[tazz]

Totally correct.....Worcester..........just checked with Samil inverter manuals, and this is not the case, the rs232 should be connected direct to the pc, the rj45 (rs485) is to link more than on inverter to a communication module

 

[herb]

Thanks for the explanation of RS232 to RJ45 I can see the problems with that now.
I have not had a PC with an RS232 port for, hmm too long to remember, plus the router is closer to the inverter than the PC so if possible RJ45 would be the best way.
As it is just one inverter would the RS485 port do it directly to the router without the need for a communication module.
If so which of the 4 pairs of wires left after cutting off an RJ45 plug should I connect to the 4 pins on RJ11 plug, and what pin numbers to use.
Thanks a lot.

 

[netblindpaul]

Well IIRC ethernet is a voltage derived signalling medial @ +/-0.85V.
RS232 is also a voltage derived signalling medium @ +/-15V
RS485 is a current derived signalling medium.
IMHO they are not interconnect-able without a signal conversion interface.
Plus on top of this then you have the communications protocols to consider.
Which will also need conversion between methods.

 

[herb]

Thank you for the technical info.
The manual points to Solar-Log but it's overkill for my needs and expensive.
Do you think this would work?
RS232 RS485 to TCP/IP Ethernet Serial Device Server Module Converter new | eBay

Thanks a lot.

 

[Worcester]

It may do, though from your earlier comments, my concern would be that you (trying to be very polite here..) lack the necessary skills to install and configure it, as you'd probably need to use something like Putty to communicate and configure it.

Have a look at this thread, and you may save yourself a lot of trouble:
http://www.electriciansforums.co.uk...orum/85306-very-quick-review-top-4-solar.html

 

[Worcester]

Thinking more about it, it won't meet your needs, as you'll still need to write an application to query the inverter and then display or transmit those results somehow / sonewhere .

Let's start again, right from the beginning:

What do you want to achieve?

 

[herb]

All I want achieve is monitor the inverter on the PC rather than have to go into the loft to look at it's display panel.
Samil provide their SolarPower Browser software application to do this, the difficulty is establishing a hardwired connection.
Someone on another forum did it with a short RS232 to USB cable into a laptop, and that got me wondering if I could get it to work over a longer distance to my PC.
Samil inverters rock!
Thanks a lot.

 

[tazz]

As from the manual....the rs485(rj45) is to network inverters together, thats all the rj45 does....the rs232 9pin is to connected to the pc and run the software. So from what i can see, your getting mixed up, and what you really need is a rs232 9 pin to usb converter, so you can run the software try this link rs232 to usb | eBay

 

[herb]

Thank you for that I see what you mean.
It's due to the distance between the PC and the inverter that I wanted to use the existing RJ45 if possible. It would be least 10m of USB cables, thinking I would need powered hubs too.

However would it work USB over ethernet, I have a cable router (not yet in use till fibre gets here) that has 2 USB ports on it.

Or, are there electronics involved in these adapter cables could I try to get a 10m RS232 cable and cut one end off and replace it with a USB plug, that would do away with powered hubs, guess it's not as easy as that though.
Thanks a lot.

 

[tazz]

no there are electronics involved to convert rs232 into usb, hence the reason for the coverter in my last post....please follow the manual, you are trying to do things, which this inverter and its software were not designed to do.