PID/SSR alternative (moved from Automated Brewing Forum)

[Snappy]

I have brew kettle with 2 kW heating element. After achieving desired temperature I need to reduce power of heating element.

Manually it works with SCR voltage regulator like this one:
http://www.ebay.com/itm/2000W-220V-A...item4d15604ffb


My SCR voltage regulator from link above has B500K potentiometer and I need to replace it with some element which I can drive from Arduinos 0-5V pin. I'm not sure if this even exists, searching for options ..

Or alternative .. is there any other component which can regulate 220V AC power for heating element?


I have found some proportional SSR's but they are quite more expensive, and they need more space and demand cooling which is hard to fit into my existing box. Any other idea or solution?

 

[user 101620]

SSRs are really the only way to do it, they are designed for high voltage (up to 600V normally) and designed for high switching rates, relays (if you're on 120V or able to find them for 220V) will generally burn out way faster than SSRs.

PIDs with SSRs work on switching "on for x amount of time, off for y amount of time".

Proportional SSRs work on reducing the voltage going on.

Ultimately both methods should use the same amount (or very similar) power in total to do the same job.

 

[Snappy]

Thank's for answer DougEdey. I'm 99% convinced that I will have to make room for SSR with heat sink.


However, still looking around and found something like digital dimmer on ebay:
http://www.ebay.com/itm/10000W-SCR-Voltage-Regulator-Speed-Control-Dimming-Dimmer-Thermostat-AC-220V-/121337846179?pt=AU_Car_Parts_Accessories&hash=item1c404c99a3&vxp=mtr

There is also some control panel which I don't need if controlled from Arduino, but I'm not sure where is logic on circuit like this (how they base board and control panel communicate). I will contact seller just because I'm curious, but this would probably be not to reliable solution (many components designed and made in China), so I will probably skip this one ..

 

[rudylyon57]

You can also use a SSVR (Solid State Voltage Regulator). Search for SSVR on eBay or Amazon and you'll find them for approx. $10.

 

[Snappy]

With SSVR I will have same problem of controling it via Arduino analog output pins (0-5V), bacuse as I can see SSVR needs resistor on command side. It's same problem as controlling dimmer circuit via Arduino.


This guy solved it via "home-made" optocoupler http://www.roboremo.com/ac-lamp-dimmer.html, but there is more similar solutions like this one

Don't like them though ..

 

[user 101620]

SSRs can normally be driven directly from Arduino/RPi/Similar things, since all the ones I've seen at 3.3v+ to switch them.

 

[Riot]

All of the SSRs I have fire from 3-32 volts, so you shouldn't have a problem driving them from an arduino's 5v out. You might need to set up a transistor amplifier if the arduino can't send enough current however.

 

[Snappy]

I was refering to SSVR (Solid State Voltage Regulator) as suggested by rudylyon57. As I can see, for this type, on controll side I need resistor. For example Control 2W 470-560K Ohm http://www.ebay.com/itm/One-Phase-SSVR-Solid-State-Relay-Voltage-Regulator-AC-220V-40A-2W-470-560K-Ohm-/321582618354?pt=LH_DefaultDomain_0&hash=item4adfd156f2

You think this I can drive from Arduino pins somehow?

 

[Riot]

Okay, that one I don't even know how to begin to approach. Might be worth posting to the eevblog forums, if it can be done I bet someone on there knows how.

 

[Brumateur]

I was refering to SSVR (Solid State Voltage Regulator) as suggested by rudylyon57. As I can see, for this type, on controll side I need resistor. For example Control 2W 470-560K Ohm http://www.ebay.com/itm/One-Phase-SSVR-Solid-State-Relay-Voltage-Regulator-AC-220V-40A-2W-470-560K-Ohm-/321582618354?pt=LH_DefaultDomain_0&hash=item4adfd156f2

You think this I can drive from Arduino pins somehow?

You can't drive that SSVR directly from arduino. To do this you need to add lots of circuitry.
SSVR is analog phase- angle controller. If you have an arduino you can do a digital phase angle controller one of example http://playground.arduino.cc/Main/ACPhaseControl