Arduino ethernet plc

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Another nice HW

Yes, it’s a really nice one but they don’t show the schematics and the ones with LAN are very expensive. Now they change from ENC28J60 to w5100 (info from support).
There is a more cheaper one from a former kickstarter campain:
http://www.digital-loggers.com/plc.html
Unfortunately no LAN but Wlan with separate ESP-IC. For a 10piece order it is only 99$ + tax + part of shipment. Somebody interested in an order?

Wireless is inadmissible for me. I’d rather went into controllino-maxi.
But it is also not ideal. I Completely dropped from driving 230V.

I agree with you. We need a wired connection. So I thought about an UART-connected LANdevice called USR-K1 (or K2 or K3). So a switch between the ESP-02 and USR could let u choose between WLAN and LAN. A future model should have an Atheros AR9331 (LAN+Wlan with openWrt) + mega2560 for gpio.

The controllino-Maxi looks professional like the Plc from industrial shields (s. above) but lags on different voltage input (12V OR 24V) whereas the other can be driven by 12V TO 24V. It’s also quite expensive and the Lan-conn. is placed in front. Maybe a 90°-Lan-conn. could be used for a Din rail case without collision. Controllino uses w5100-ethernet-ic, which safes some memory.

I decided to definitively exclude control 230V from the project. Lighting will be 12 -24 V. And in the controlled outlets I do not see any sense. Only through local actuators via CAT7 cabling (just a few things). Does not add me into consideration anything that has power relays. Useless waste of money.

In the first flat I am finally at the stage laying of the cable. For the purchase / construction of control units I have about 4-6 months.

Both switchgears are separated (very safe). I focused mainly on proper wiring. About 870 m CAT7 + many empty electro pipes in 65 m2 flat. I refused any bus and all cabling will be strictly to the star topology. My daughter lives in this apartment. After this test, begin to remake cable distribution in my upper flat.

I’m trying to build it so that the cables would have maximum versatility. Who knows what will happen in 20 years.

So far my favorite is M-21 Arduino Duin PLC I / Os Analog / Digital(or greater) and extending over 20 I / Os PLC in the future.

Laying the right cable is important. 10 years ago I have done this with Cat5e an luckily I spent the money on a 24-port rack. Thats my backbone for the wired iot now. Also I like this: "If you know wifi => take cable."
I got some E-mail-support from Controllino yesterday. The different voltage range is only because of an automatic switching of the Input-voltage divider (analog in). It can be fixed to 12V or 24V and then you can use the full power supply range from 10.5 to 30V. Nevertheless the Maxi is 200,- Eur + tax .
But I checked the schematic and I like the usage of all 4x Rx/Tx where Rx0/Tx0 is used for USB and Rx3/Tx3 for RS485 Modbus/RTU. Rx1/Tx1 & Rx2/Tx2 are free for own usage.
Bringing a 230V AC-switch to a separate Din Rail holder makes sense so an more expensive “relay-session” on the PLC is not necessary. Unfortunately the M-Duino has a terrible form factor at the DIn rail. Looks out the front of most of cases . The advantage is that you can use a cheap Mega2560-clone if something goes wrong on the PLC. Maybe I rotate it 90° + new rail holder. Asking for the Wiznet w5100-version would make sense.

Hello wutu, what about a new selfmade PLC? I realized an individual board 2 years ago but it was too special for given the requirements (heating controller for water filed oven). Now I would prefer a strong usage of ebay-modules to save costs. So 2 days ago I discovered a long missed 2560-µC-module here: http://www.ebay.com/itm/New-Small-Meduino-Mega2560-R3-Pro-Mini-ATMEGA16U2-Arduino-Mega2560-Compatible-/161757302117. What do we need in addition?

• Analog input => How many? Is 0-5V enough voltage range?
• digital IO with optoisolation => How many?
• PWM output / 0-5V output (with RC) swichable => How many?
• Real time clock as module=> which one do you prefer?
• LAN by SPI-bus (W5100) switchable to optional new SPI-WLAN-module http://www.exp-tech.de/adafruit-atwinc1500-wifi-breakout
• usage of all 4 hardware uarts
• I2C connector
• display yes or no? for information 20x4 LCD (@ I2C) or a µC gentling Nextion TFT with own processor?
• DIN rail case => of course but which one?
• Relays could be outsourced (cheap SSR-modules at ebay) but what about Mosfets for DC-switching?
• Do we need 12V-24V input voltage? I think only when output level should be at this level this would be necessary.
• something forgotten?

greetings from iot

Hi guys

Have you looked at UniPi? I have one, but still in the process of getting the hardware mounted to connect to it.
It is not that expensive either. There is a mounting kit for DIN rail as well.
It uses a Raspberry Pi as processor, so that fits in nicely with Pimatic

and we’re having a nice plugin for the unipi
https://github.com/mwittig/pimatic-unipi-evok

Yes - I own an UniPi and it’s a nice piece of hardware (+ evok-software).
https://drive.google.com/file/d/0B6lNUASUD83URFBRRjZmNVFHczg/view
http://unipi.technology/forum/viewtopic.php?f=14&t=108#p378
And many thanks to mwittig for the plugin
But if you need smaller controllers without operating system the AVRs are more reliable and have plenty of IOs with hardware-PWM. Also they have no problem if power fails whereas RPi & Co. need an UPS for a save shutdown. A small PLC based on MEGA2560 with extensible modules (relay, LCD…) and on DIN Rail would be nice for sensor-/actornodes which could be controlled by node or pimatic. Unfortunately the 3 PLC here

• a from industrial shields
• b controllino and
• c Wifi PLC from US

are expensive (c only because of high delivery costs - for 10 pieces its only 99$ + shipping). So the homeduino-hardware here: http://www.stall.biz/
looks in the right direction. I thinkk it has nothing to do with leader21s-433RF-plugin.
Unfortunately the stall.biz-hardware is a bit too big, no DIN Rail, some missing parts (0-5V out, RS485) and looks more for hobbiest. I’m looking for a more professional touch with IO-protection, 0-5/0-10V output options and RS485/Modbus-RTU to control external devices like chargers, grid-tie inverters and so on. These devices need an absolut safety operation where I would prefer the big 256kB 8bit µC (with own C-program / sketch - maybe combined with configurable firmata).
greetings from iot

Ok - lets start with a new PLC - called “iPLC” - The ideal PLC
Please give hints and advice to optimize YOUR PLC.
From the mega2560-schematics I can see:

• 15x PWM
• 16x Analog input
• 41x IO
• SPI: Miso, Mosi, Sck, SS
• 4x hardware-uart (Rx/Tx 0…3)
• 1x hardware-I2C (SDA, SCL)

Main features
Because of plenty resourses we don’t need double functionality of Pins (no switches).

Main question? The input voltage range: 0-5V, 12V, 24V or 10 to 24V? The answer applies to analog input and pwm/analog output range

Pwm <-> Analog out, switchable for each channel, above 5V input => OPV necessary
What kind of protection?

All 16 ADC to connectors?
What kind of protection?

IO wth optos for protection
How many IOs to main connectors?
some IO with mosfet, some with ULN 2008, How many?

Buttons? Difficult to fix on the case.

uart0 is used for USB, uart1…3 => free (for external devises Nextion-TFT, GPS, ESP8266…) => ext. connectors

SPI would be fine for LAN (w5100), optional WLAN-Adafruit Minimodul Atmel Atwinc1500, SD-card
LAN/WLAN switchable because only 1 way to your Ethernet at the same time? no WLAN saves power.
For Wifi-data (sensors) the ESP8266 with uart could be used.
all modules from ebay &co. and inside the case? What else?

I2C could be used internally (RTC) and with external modules. Would prefer buyable ones.

Do we need logic level converters for 3.3V parts?

I used the very small green/orange Phoenic contact conn., which are very reliable. They are the smallest I know (RM 2,54mm).

Small Din Rail case
Bye iot

I’ve seen this topic several times, bit it is still unclear to me what the purpose of this device is ? Can someone explain me in simple language what’s all the buzz about is ?

https://en.wikipedia.org/wiki/Programmable_logic_controller

Thanks Wutu.

other short answer:
A PLC is used in the real world - less in the prototyping world / maker scene.
Often it’s characterised by:

• DIN RAIL mounting
• professional connectors for wiring devices
• electrical protection of In- & Outputs
• protecting case (against dust…)
• 12…24V supply
• sometimes extensionable with DIN Rail modules

In former times they were very expensive parts of the industry. Now it’s changing due to Arduino & RPi.
But with “iPLC” we try to get nearly all possibilities of the powerful and very cheap Meduino 2560 R3-module. Combined with reliable cheap ebay-modules (w5100, RTC, Adafruit WLAN, LCT, Nextion-TFT …) it could simplify the step from DIY/maker projects to real world projects with their higher safety requirements.

To design “iPLC” I need your requirements. In addition to the list above I want to add an RS485-IC on Rx3/Tx3 (like controllino/industrial shield) and a 1-wire master-IC for long distance bus line with more than only one 1w-sensor/actor.
Also an equal or similar Pin-usage of the existing Mega-PLC would be preferred. Don’t like to invent the wheel twice.

with best regards
iot

@Hr-FS nicely outlined

First, I think right now if I PLC construction pays off. Material plus time.
So far, is better buying profi PLC for me (my favorite is the Industrial shields for their scalability). 100 Euro + does not come to me so much.

But do not oppose the building if it is worth. And I need a really simple PLC for start.
about 20x I/O
6x 0-10V analog output
LAN port

It would be great if the PLC has 0-10V, 0-12V and 0-24V for analog / PWM.

It was in a protection circuit unfamiliar to such an extent. Only simple things.

mosquitto_pub -t pimatic/forum -m Bye

Ok - but the actual buyable Profi-PLC aren’t perfect (AND expensive).
Do we really need an output level of >10V for PWM or voltage? I only know 0-5V, 0-10V and 4-20mA inputrange for device control.
What about a fixation of all 15 hardware-PWM-channels to small connectors in the following manner? The connectors could be placed DIY only for the required ones (saves a bit money).

• 8x 0-5V analog output (for devices) / switchable to PWM with 5V level (=> 8 servos)
• 7x 0-10V analog output (for devices)

Also to save costs only 1 power supply voltage would be nice. If we choose 24V you need a 24V power supply and maybe a bigger UPS (2x 12V Pb).
12V would be a good compromise because the 10V level should be simple generated and mosfet / relay control is easy. Internally we use 5V for the Mega and 3.3V for some modules (with step downs smooth voltage necessary because of ADC ).
If desired a UPS with 12V_in (power supply), 12V_out (to PLC) and 4S Lipoaccu could be: http://www.bestechpower.com/cmbforbatteries/UPS-H284.html
If 24V-analog output is really needed it could be generated with separate step-up. The mosfet / relay-part still lies on 12V DC.
Something wrong?

Ok, I like to save.
24V I wanted to use for ordinary 24V LED via CAT7 cables. So, just I need a larger current. Moreover, it would not need immediately.

What to build a versatile unit? On the basis Mega2560 R3 Pro Mini + Eth + Din Rail case. And let the people at the figure of the “end stage”.

I would think a couple of times in the rack unit cloned each with a different or the same “final stage”. Everyone should be self-contained, with its own Ethernet. Everyone in variously sized DIN cabinets. We would thus obtain a decent system resilience to failures. Data to the terminal board, would be passed by a “larger connector”.

The next question is where to get the software.

This Arduino mega mini is not exactly easy to come by (this could be a problem).

What use something like this with ordinery Arduino Mega?

EDIT: Perhaps more affordable for us http://www.aliexpress.com/store/group/Industrial-Automation-Control/316973_260464749.html

We have to make a decision if switching of power devices should go to an outside board or not (it’s possible every time through I2C-bus-conn.). I think your 24V LED-stripes for lights are real power devices.
advantage: If relay or Power-Mosfet fails there is a clear border to repair one part and Mega2560 with the IO/PWM-motherboard could go on.
disadvantage: extra DIN Rail case for external power switching board, extra connectors with extra wiring
But we have plenty of IOs which could be directly used on 1 PLC motherboard. If 1 part (relay/mosfet) fails here, the motherboard must be repaired but the Meduino2560-board is also cleanly separated because it’s a cheap piggyboard. Also the power copper lanes on the motherboard (MB) are very short (external power cable goes into connector 1 -> relay/mosfet -> comes out from connector2 - that’s all. Do not use power lanes through the whole MB

=> I would prefer to design ONE motherboard/ ONE case with place for all the things of above list, but only implement the used parts. Of course the small and cheap SMD-Rs and Cs must be completely welded on the board. ICs for 1-wire, OPV and RS485 should also be mounted. It’s a bit more expensive but welding SMD is not an every day task. The case length would be ~100…160mm to realize a fully featured MB.
What really need space on an extra DIN RAIL holder is a big TFT / LCD. But it’s used not very often. Maybe the top side of iPLC can designed for a LCD/GLCD, but which one? We loose flexibility.

For switching your 24V LED-stripes I recommend:

• DIN RAIL 12V power supply for iPLC
• DIN RAIL 24V power supply for LED
• DIN RAIL iPLC (with 8 relays + 8 PowerMosfet or how many we want)

You plug the 24V-plus cable to the Mosfet-conn. on iPLC so you don’t have to carry high currents due to 12V. Mosfet instead of relay if you want to dim with pwm.
Every iPLC includes a connector inside for the cheap W5100-LAN and optional WLAN (SPI)-modules + external connectors for all UARTs + I2C…
So we can use it with ethernet or not. Also bluetooth should be possible with module (UART or SPI?). A very flexible system.

Question: Will you drive the LEDs through the CAT 7?

The linked green extension board seems not having Mosfet/relay for switching . So you have to tinker again and that’s no PLC-style. The only thing that the green PCB does is bringing the RM 2,54 of Meag2560 to a srew terminal.

software: Because we use only the full range of standard IOs there should not be problems. To software it’s a normal Mega 2560

Hello,
checking the max. account of connectors a case with 2 stackable PCB could close fit. Length would be ~107mm.
LAN-conn. is problem at the moment. I don’t want to loose IOs because iPLC stands for ALL options.
iPLC (case & connectors)