|Monthly Tech-Tip |
Notice the 220V enters lower left to a terminal block. That splits to a transformer (above) and relays (below that). The 4-07-6024 transformer supplies power to the SMT_3140 controller board (converting the 220V down to that needed by the circuit board). The controller is run by an MSP430 Texas Instruments microcontroller (lower left has closeup). That controller has inputs from the thermocouple and a current monitor (yellow donut shape around the wires going to the elements). The board has outputs that connect to the relay, that relay in turn controls the flow of current to the elements. This is a very simple appearing device, but not something to be replaced lightly. DIY controller boards documented online look tempting but they are not CSA or UL approved (so your fire insurance coverage is implicated). Commercial controllers focus on safety and liability over functionality, they handle intermittent thermocouple connections, bad thermocouple readings, stuck relays and shorted and weak elements - these are runaway conditions that could become meltdowns in a kiln controlled by a DIY device. This being said, these commercial products do have a weakness: The relays. They are mechanical devices and are the first thing to need replacement. Kiln controllers are thus particularly good at recognizing relay failure.
Kiln Controller Device List
If you are aware of devices not listed here please contact us. We want to focus on those in active development. Devices supplied on manufactured kilns are usually relabelled, they are not actually made by the kiln manufacturer.
In ceramic kilns the firing schedule is typically managed automatically by an electronic controller. But that may not mean that ware gets automatically fired to the correct temperature and atmosphere.
Build a kiln monitoring device