@tridiumcontrols1 this is the only picture i have. the schematic of the control panel.
so we can tap to the genny and forget about the feedback. because you said a few tens of milliamps wont affect anything.
can you explain to me how can we do the interfacing with the genset?
Alright, I had to log into my other account to be able to post more than 2 links.
Picture is blurry, any chance you can upload a better copy? I can tell you where you need to land the communication wires.
Also, since you have the easygen 2000 controller panel you already 75% there, refer to this document, starting on page 47, which talks about the easygen 2000 modbus capability.
which also has the easygen 2000 modbus points, and look at the address table for the generator on page 77, look at all the points you can pickup via modbus communications. Also on Page 10 of the manual it explains what type of interfaces you need to connect to what device. IF you have the Easygen 2000 then you wull need a RS232 to a TCP converter, if you have the easygen 2500 then you can use RS485 to TCP converter.
Here is what you will need to accomplish this. Hardware/Software Required.
- Raspberry PI 3
- EmonCMS image file, burn this image to the sd-card of the raspberry pi.
- MODBUS RS485 to TCP Converter, which converts the 2-wire serial interface to be used over TCP/IP connection
I recommend this one, Modbus RS485 Adapter - NET485-MB – Grid Connect
or something similar, but it has to convert Modbus RS485 to TCP, maybe a google search in your area can shed some light on where to purchase this.
Grab a raspberry PI3, and download the emoncms raspberry pi image, which has “NODE-RED” installed by default, which has the which will poll the generator for the modbus points, and then you can use node-red to send the information to emoncms via the JSON API.
emonCMS Raspberry PI Image: emonSD pre built SD card Download & Change Log · openenergymonitor/emonpi Wiki · GitHub
After you download and burn the SD card image from the link above, you will have node-red access.
Then you will need to install this
node-red modbus TCP: node-red-contrib-modbustcp (node) - Node-RED
which you can use node-red to poll the genset modbus points, then use JSON API from emon CMS to publish the data to emonCMS for logging and trending.
How familiar are you with JSON?
I know this looks complicated, but it is not, and very easy.
Let me ask you this, what is this generator for? a big company? server farm? to be able to output 1MW means big power, reason I ask is if this is for a building, do you have a building automation system? perhaps a JACE, which then you can do away with the hardware and software above, and purchase the modbus license and its much easier then.
Do i really need modbus rs485 to TCP converter or can i just use rs485 to USB serial conveter to connect it to raspberry PI?
sorry to say, we dont have much knowledge with programming and stuff. hope you understand. but we are willing to know and try everything. thanks.
thats our best photo of the controls. the schematic was supplied to us like that. sorry i know its really blurry. but that the only photo i have.
our generators are grid connected. we supply power to remote places here in the Phil. our gensets range from 100KW-1MW per unit. the number of gensets depend on the demand from the place.
and we are not really familiar with the JSON API.
That’s alright, I’ll assist as much as possible, and somehere can assist further on the JSON APi, but first we need to establish modbus communication.
On the genset it self, can you look on teh back of the control panel it will say whether this is a easygen 2000 or a easygen 2500, this will give us the correct route to continue with this.
You can do either way I suppose, connect RS485 to USB and into the PI, just got to confirm the drivers are available so that linux can see the rs485 device.
Reason I recommended the converter is because you can connect multuple gen sets together, but if you will use the usb rs485 then you will have 1 connection to a genset.
Instead of the node-red modbus tcp component, you can use this one.
which allows for both modbus tcp and modbus 485 serial.
we think its easygen-2500.
how many gensets can we connect if we use the TCP converter?
If you do have the easygen 2500 panel then it talks modbus RS485 and your modbus data lines are on terminal 102/103 - Refer to PAGE 11 of the manual.
Modbus states the limit is 32 devices, connected in a dasy chain fashion, so in theory 32 gensets on one data line, all dependent on the amount of data you will be pulling from each genset. If you only pulling volts/amps/frequency/generator temps, pressures, engine RPM, and any alarms which is roughly 15-20 points per genset, then you should be ok with 32 devices, but I would not recomend putting 32 devices on one dataline, at least 10-15 devices is recommended. Length of the communication wiring limit recommendation is 4000 feet.
Are your gensets next to each other?
yes. the gensets are next to each other. but we mostly have just 3-5 operating gensets.
These two Python packages support Modbus.
Minimalmodbus which as the name suggests is a trimmed down package compared to PyModbus which is a full blown implementation.
I use Minimalmodbus, an RS485 to USB converter and a RPi to read two headless Watt-hour meters.
It sounds as if you should be able to use a similar setup to read your genset.
Perfect, if you can confirm you have the easygen 2500 panel, then you can use the rs485 converter and connect all genset together, and use one raspberry PI and have one emonCMS application running gathering information across all gensets. I can draw a schematic on how this will all look, just need a confirmation you have the easygen 2500 panels and not the easygen 2000 panel as this will change the way communication occurs.
which easygen series is more complicated, because we would like to ask you to give us the more complicated one and we will try to do the other one. thanks
thanks. ill read about this
The easygen 2000 is bit complicated.
Here’s the difference between the two.
EASYGEN 2000: a PEER-to-PEER communication, meaning only 1 raspberry pi per genset, this type of panel cannot be daisy chained to other gensets, this one genset will have 1 raspberry pi, 1 usb to RS232 converter, and it will be alone.
EASYGEN 2500: can communicate to multiple gensets on one modbus data line, and requires one RS485 to TCP converter as I stated earlier.
I can draw you a schematic in little bit of how the network will look like for each type of panel.
okay that would reallybe great. thanks.
Alright, I know the sketch looks rough, but here’s the general idea, RS232 vs RS485.
RS232 is used if you have EasyGen 2000
RS485 is used if you have EasyGen 2500 control panel.
@tridiumcontrols1 I get the sketch. now comes the other problem. how can we congifure that? the parameter we need to measure is power(voltage/current)/load and Speed if applicable. so how?
@tridiumcontrols1 Can the single RaspberryPI process data from an arduino (connected to sensors) and at the same time data from the control panels thorugh modbus/TCP converter?
this is just in case that there are different gensets with different control panels (aside form easygen), which is I think is true in some of our plants raspberry will also send data through GSM modules, this is because our plant sites, are located in missionary areas where internet is out available anywhere.
is the connection of the ModBUS TCP to Rpi3, RJ-45 (ethernet cables like CAT5E)?
Question… Why RS232 to USB, but RS485 to TCP?