Personal Project - need suggestion - PID + thermocouple cheap !?

[bce123]

HI JNT, I have a 260 cpu with a c-more hmi that i yue to run trending on ovens and i also use it to tune them with however these are gas fired with mod motors but my point is it works great and is easy to use the c- more has usb data loging capacity.the ad team also has the best free support i know of.that said keep in mind time is money and if you dont have much experince with plcs i would use the 260 or the 06 the direct soft program is very user freindly.and no i dont work for them but have used them for many years wih great results.and they can ship over night if you need parts in a hurry.

 

[keithkyll]

Try 8 temperature controllers. Built in RS485 with Modbus. Free datalogging software. See last page of Chapter 6.
Still need a PC and SSR's.

As bce123 said, the HMI does datalogging. You don't need the comms module. The lower priced units don't have Ethernet. Don't know why you need it. With the MT6050I, you can log to a Thumb drive, or send data to a PC on one of the extra serial ports.
Assume you can do similar with C'More and others.

 

[GeoffC]

This might be worth a look
http://www.tri-plc.com/products.htm
seems to have what you might need for a couple of hundred dollars, I would look at an ethernet model and use either the built in web server or Archies free hmi (via ModbusTCP). Only issue is the analogs are only 0-5Vdc (from my quick look) so prabably depends on your temperature sensors

 

[JNTurcotte]

This might be worth a look
http://www.tri-plc.com/products.htm
seems to have what you might need for a couple of hundred dollars, I would look at an ethernet model and use either the built in web server or Archies free hmi (via ModbusTCP). Only issue is the analogs are only 0-5Vdc (from my quick look) so prabably depends on your temperature sensors

That's quite interesting. It's small and not too expensive.

Unfortunately, looks like there is only 2 Analog Input. But I emailed them, so I will see.

I would have to find some temperature sensor that would send an analog signal that the nano plc could understand. Signal Conditioner I suppose is the only option ?

 

[GeoffC]

Unfortunately, looks like there is only 2 Analog Input

If you go for the FMD88-10 it has

• Built-in Ethernet port - Support MODBUS/TCP
• Programmable via the Internet
• 8 inputs (24V NPN), 8 outputs (6x1A, 2x8A @24VDC)
• 8 analog inputs (12-bit, 0-5V)
• 2 analog outputs (12-bit, 0-5V or 0-10V selectable)
• 1 RS232 port, 1 RS485 Port - support Modbus RTU and ASCII
• 4 Pulse Measurement, 2 Encoders, 4 PWM outputs
• 2 channel Stepper Motor Controller
• Very Fast 32-bit CPU
• I2C option for future expansion

for US$229.00 for the starter pack

I haven't used one but am also planning a personal project (pool automation and heating control) and this looks to be what I will use

 

[GeoffC]

As for sensing temperature I will probably use an LM335 opamp, or a thermistor. A little more work with the thermistor since it is a non linear output, so would require a conversion calculation (or lookup table)