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[on:]

I have a project in work where i need to control a Hotpress machine. Hydraulics close and open the press, this is controlled manually. I require a controller that will take as inputs of time and temperature (entered by operator) for each of the 5 plates. Temperature will be maintained for the duration of the time inputted, when time has elapsed temperature is switched off and an alarm siren is sounded and the light tree goes from green to red.
I was told that an Arduino board would be capable of achieving this control. I have never used or even heard of them until this week, can anyone give me advice on what board would be most suitable. I can program in C but i have never programmed a controller like this.
Any help would be greatly appreciated.
Dave

[Reply #1 on:]

You need to figure /decide out how you will (can):

Control temperature
Read temperature
Control the hydraulics
Input time / temp parameters

before we can give any advice.

[Reply #2 on:]

Thanks for the swift reply.

Control temperature (Thermostat will control temperature. I'm thinking operator will set individual thermostat temp separately but power to these will be controlled by board. Is this possible)
Read temperature (There are thermocouples built into the plates, type J i think but need to confirm. These will be wired to thermostat)
Control the hydraulics (hydraulics are controlled by a separate system which is controlled by the operator.)
Input time / temp parameters (Undecided on time input. some form of digital input but open to suggestions. Temp as described above)

These are second hand machines we bought, the company we bought them from stripped them of wiring and control. I was considering having an engineering company wire this machine and add control. However the costs are prohibitive, i could get an electrician to wire and add the control myself but i haven't done anything like that since college. and it was all PLCs then.

[Reply #3 on:]

You can probably control the power to the heating elements with relays, that is rather easy with Arduino, of course you should know what you do as it involves potentially lethal voltage and current levels.

[Reply #4 on:]

I will be working with an Electrical Engineer on this project so we should be reasonably safe. He is going to wire the machine i'm am going to work on developing the control aspect. Relays make sense. I'll need to spend some time studying the capabilities of the Arduino to decide what is the best solution. There seems to be a range of various Arduino boards available, could you recommend which would best suit this project. I do not need to communicate with the board once it is set up and running so I don't need any bluetooth or wireless connectivity.

Thanks for your help

[Reply #5 on:]

I require a controller that will take as inputs of time and temperature (entered by operator) for each of the 5 plates. Temperature will be maintained for the duration of the time inputted, when time has elapsed temperature is switched off and an alarm siren is sounded and the light tree goes from green to red.

Are you actually planning to have the Arduino control the temperature? You talked about using an external state subsequently, in which case the Arduino doesn't need to do anything except turn the heater off and switch the lights over when the time has elapsed. Depending on the length of time and timing precision you may not need to implement your own solution for that - all you need is a timer that will turn something off after a delay - use that to switch a twin pole twin throw mains voltage relay that powers the green lights + heater in one position and powers the red lights in the other position. You can buy domestic timers to do that off the shelf for a few quid. Using off-the-shelf components to control the temperature and timing would give you robust and user-friendly controls and save you a hell of a lot of work.