Help with electric controller

[hotkarl]

Ok so I am not exactly electrically savvy person, but I have built a control box for my 5500w water heater element. I am using a solid state relay with a potentiometer to control it like the diy controller from stilldragon.com. I have seem to have run into a little problem though, when I am testing the output voltages with everything hooked up, I am getting a voltage range from ~236 to 241V. My ssr and pot models are as followed:

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I have hooked everything up like this:

Still.pdf

(22.78 KiB) Downloaded 194 times

Any sort of help would be greatly appreciated.

[rad14701]

Are those voltage readings under full load using the element...???

Did you get a 2W 500K Ohm potentiometer...??? I didn't see the rating stated...

[hotkarl]

Those readings were taken from the lowest setting of the pot(236v) and the highest setting (241v). That just doesn't seem like a big difference to me. As far as the pot goes, it's 500k ohm but I'm not sure about the power rating. I'll check and see if I can maybe find it somewhere on the knob. Would I need a 2W model to control it?

[rad14701]

Those readings were taken from the lowest setting of the pot(236v) and the highest setting (241v). That just doesn't seem like a big difference to me. As far as the pot goes, it's 500k ohm but I'm not sure about the power rating. I'll check and see if I can maybe find it somewhere on the knob. Would I need a 2W model to control it?

They are usually spec'd for 2W but it might work with lower wattage... I'd unsolder the potentiometer and test it with a multimeter set to Ohms...

[MuleKicker]

Forget voltage, you need to be measuring current flow... AKA Amps. With the load hooked up, ofcoarse.

[sensei]

Where exactly were you measuring your voltage, from neutral to the supply, or to the element?

[sambedded]

Do you have your load (heater or lamp) connected when you did measurement? This SSR doesn't work with no load.

[bellybuster]

1/4watt pot should be fine. Should say right on the SSR. Make sure you don't have anything attached to the third lug on the pot. Also that SSR has a resistive range of 470ohms-500Kohms, you need a 470 Ohm resistor in series with it.

[hotkarl]

When I took the measurement, I just hooked my multimeter to the end of the wired coming off of the controller with nothing attached. I'm guessing I need to hook an ammeter up with my element in the circuit and give it another go before assuming I got the wrong parts. Thanks for all the help guys

[rad14701]

When I took the measurement, I just hooked my multimeter to the end of the wired coming off of the controller with nothing attached. I'm guessing I need to hook an ammeter up with my element in the circuit and give it another go before assuming I got the wrong parts. Thanks for all the help guys

The controller must be under load to have an accurate reading... It won't push power into thin air, it requires a resistive load...

[mystakilla]

Not sure what your question is?

You are getting the voltage you need so what is the problem you are having?

[sambedded]

Forget voltage, you need to be measuring current flow... AKA Amps. With the load hooked up, ofcoarse.

It doesn't mater what to measure voltage or amperage if you have a load connected.