开云体育

1k to 10k is common, ?for relays?

You do not want to use a relay (EMI), but an SSR with crossover detection, also called zero voltage switch. I? use my own PWM method by enabling X periods over a one thousand period timeframe. 1000 periods at 60 hertz is less than 20 seconds, so I can finely tune the temperature ramp in real time.

Thanks.? By the way, I just ordered a reflow controller from Rocket Scream who just got theswe back in stock. A lot of bang for the buck.
Full schematic, design files, user manual available.

Jim,

I originally used a Silicon Horizon reflow oven controller board which cost around $75. I tested it and then put it up on a shelf until I got around to track down all the remaining parts to do the actual build. I bought via Amazon (its generally a crap-shoot regarding product quality in my opinion), a Black & Decker InfraWave 1200 Watt with crystal heating elements (exhibits shorter thermal inertia) instead of the iron heating elements. I hacked out all the guts and then lined the insides of the oven, between the inner and outer walls of it with high fibre-glass insulation sheeting, which I custom fit. Else ya can't touch the oven while it is operating. My unit is cool to the touch, even during 36 hour component baking periods. When I got the controller down, it worked three times and failed. I contacted the company and it had gone out of business. The schematics & source code had been promised to be on the CD shipped with the controller, but alas was not. So I reversed engineered the hardware and fixed it and in the mean time I acquired all of the source code from other users.

To make a long story short, I eventually replaced that controller with the following, excellent controller:


Depending on options it starts at $100 bucks, for the controller and the display screen. It works very well and I've used it for many projects over the past 7 years or so.

What ever you do, be sure to acquire the oven with an internal fan. The B&D Infrawave does not have one internal, so I had to mount a small blower on the outside. Also the 'gold' thermal reflection tape really makes a difference in the internal thermal cavity stability.

Best Regards

tron nee

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SETV - Autonomous Instrumentation Platforms for the Detection & Measurement of Suspected ExtraTerrestrial Objects