BTA40 triac

[jjj]

Hi to you wonderful Experts,

To control a water heater of 3KW6 at 220V I bought a couple of BTA40 triacs.

My friend bought a Chinese dimmer with BTU40 and I copied it (see attachment).
The Prob is that it has to use a 2W Pot and they're not cheap.
Q: Is there a way of curbing the current to the Pod so that I can use an ordinary Pod, instead?
The circuit below the Chinese one I found on the Internet. This one did not ask for a 2W Pot.
Please check if that's right, for I don't want burn them out, just to find out.

 

[alec_t]

The second circuit won't work as a practical dimmer or power control. A 10k pot / 0.1uF combo has a time constant of only 1mS, so the triac will always turn on very shortly after the mains zero-crossing.

 

[canadaelk]

You should be able to get by with a standard pot. If you google "triac light dimmer circuit" you will get lots of hits. Note that most of these have an LC network to reduce RF introduction into the mains. E