Welcome to the N1IR Electronics Website. Totally off the cuff, one take, unrehearsed video projects for anyone interested in amateur radio, electronic design, makers, hardware hackers and science.

Get off you duff and build something!
Training the hand and mind since 1982.

Monday, December 8, 2014

Projects on Steroids

Finnaly I can post again after finishing my last class.

Here are a couple of project I've been working on.

First is a 40 amp triac phase control for my electric water heater, this was built so I could reduce the wattage of the hot water heater, this was done so I could run the heater off my genset if we had power loss. Yes it works! and yes it takes longer to heat the water but it does not tax my genset. If I hooked it directly up to the genset it would be at it's maximum wattage rating. I have cut the power in half to around 2KW. Why not use a diode? Well that would tax one phase of the genset more than the other not a balanced load, by using the triac I can control both sides of the sinewave. Photo are below

I used the guts of a dimmer switch and swapped traics, you can still see the old one mounted next to the pot. The triac is rated for 40 amps or 9600watts, the heater has a max of 4500 watts. The heat sink is off of a solid state relay. I ran without a heat sink and the box got warm to the touch so I over killed the heat sink. Out of the box it min pot resistance I run about 2100 watts, at max 4000 watts. Used 10 AWG solid wire soldered directly to MT1 and MT2.