Advice

[Guest oco]

I'm currently working on a project which involves the build on an online monitoring system which displays the status of power distribution / switchgear components. We need to read a standard range of information from approx 18 components which include Amp, Volts, PF, kW and status I/O information to a PC which will then compile the data and send it to a remote database at which point we can build the monitoring system. We have managed to find a way to read the Amp, Volts, PF, kW via software and hardware supplied by a company called elcomponent the only problem is they do not read the status I/O information and we have been informed that the only way of doing this is via a PLC. So basically I need to compile the data from the elcomponent software and status I/O information from the PLC and then via ODBC upload the data to the remote server. The elcomponent metering software is access based so I’m thinking I can use the access database to do the compiling tasks and the uploading of data via ODBC. So my question is what is the best way of getting the data from the PLC and into access. Any advice would be much appreciated!!!! Note: The PLC where thinking of using is a Mitsubishi Alpha switchgear.pdf Edited 20 Feb 2004 by oco

[Guest Guest]

Firslty i am not familar with the alpha PLC so i will answer the question with an Omron basis...sorry.. Looked at your pdf diagram and it seems to complicating things a bit if i may say so..... From what i understand you have 18 power monitors for lack of a better description and 36 (18*2) status bits ON/OFF, Volt free am i right. Also you want to get all this data to a remote location. The next questions are how far is this remote location ie a local phone call, or could you use radio modems ??? Secondly what types of communications protocols do the power meters talk with. I will assume modbus. By monitoring system do you mean a GUI - graphical display of gauges say that will display the AMPS and log these to a SQL ? database.... Might i suggest we take a step back before even comtemplating ODBC..... Have you ever considered a SCADA package - Supervisory Control And Data Acquisition These programs are off the shelf and can do pretty much everyting that you want. Ie remote connection, display, logging to a database, text csv file,alarming etc Suggest configuration: Omron Local end 1 off CJ1MCPU12 - CPU 1 off CJ1WPA202 - Power Supply 2 off CJ1WID212 - 16pt Input card 24Vdc 1 off CJ1WSCU41 - Serial Comms card with 1 X RS232 and 1 X RS485 port (The serial card will be programmed with a modbus master protcol to talk to the meters thereby we only require a single communications interface to the PLC to get all the information to the remote location) 1 off Modem Remote End 1 off CX-Supervisor - Omron SCADA package Programming acc. 1 off CX-Programmer 1 off CS1WCN226 programming cable. Assuming we can use a standard modem, in this configuration there is no need for a computer at the local end runnig MSACCESS. Oco, i don;t know what part of the world your from but i am sure that there are a number of local integrators in your area that could help you with programming and configuration. I hope that can shed a little bit of light on a different approach... Good luck...

[Sleepy Wombat 27]

Sorry that was me, forgot to log in....

[panic mode 246]

Alpha is just a smart relay. The only port I've seen on Alpha's is the programming port. Do you have driver that can talk to it? For similar (slightly higher) price you could get FX PLC if you want to stay with Mitsubishi. This will have advantage that you can get driver to talk to it or you can write your own. Some sample code is posted in the download section of this forum... Edited 20 Feb 2004 by panic mode

[Guest oco]

Thanks for your reply Its good hearing a new opinion. We are based in london in the UK and just to give you a bit more info of what we are trying to do... Regarding your first question; The system we are building for the remote monitoring is going to act as a monitoring / live chat support / knowledge base. The application will be held online and accessed via the internet. We are building this area of the project bespoke so we wouldn't need the CX-Supervisor software but we will need to post the monitoring data to the remote database where the monitoring site will be hosted. This is why we where looking at ODBC. Secondly I'm pretty sure the communications protocol used is modbus Regarding the PLC were open to options (The most stable product within a budget) We have been informed that the SCADA option can be quite costly and that has been why we have been looking at the alternate solutions but out of interest do you know how much the CX Programmer software normally retails and developers charge?

[Sleepy Wombat 27]

Ok look at the system configuraiton i offered....... Thats the way i would go... and if you were looking at an alpha originally you might get a bit of a shock in the price diff.... The only tricky part would be loading the Modbus master software (which requires CX-Protocol) but once done, it done.....I am sure that who ever supplies the equipment would load it for you free of charge. CX-Programmer V4.0 is Aussie Dollars is $1400... Looking at what you want to do would require a minimal amount of PLC programming. Allow for one day.... If you are familar with VB and developing your own appllication then from this site in the Omron download section you can download an excellent VB Omron communications sample program submitted by Jay Anthony. You mentioned that SCADA could be quite costly....But you also mentioned reliability was a key factor... Hence why i suggest SCADA originally... I am also familar with another product not relaesed yet that can talk to the omron PLC's and act as a web server while logging to ans SQL DB and trending data. In fact it has the potential to talk to a number of devices.