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  • Electric Brewery Control Panel on the Cheap

    250mm tall x 300mm wide x 150mm deep

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  • Electric Brewery Control Panel on the Cheap

    You would just wire the SSR output to energize the hot leg of 120VAC pump outlet instead of the black leg of the 240VAC for the heater element. For the relay, you'd wire the black and white wires from the pump outlet to the relay instead of the black and red. You would have to tune the PID but should be able to use any one suitable for the project to drive the pump instead of the heater. I think.

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  • jmengel commented on jmengel's instructable How to build a garage from the ground up1 month ago
    How to build a garage from the ground up

    Great to hear. Good luck with everything. Our garage is still going strong, even supporting a 12 panel solar array.

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  • jmengel commented on jmengel's instructable Electric Brewery Control Panel on the Cheap2 months ago
    Electric Brewery Control Panel on the Cheap

    Fuses are a good idea, but my build was focused on low cost, which means low part count. Feel free to include a fuse.

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  • jmengel commented on jmengel's instructable Electric Brewery Control Panel on the Cheap3 months ago
    Electric Brewery Control Panel on the Cheap

    You missed something. 220V is created by the two "hot" 110V lines (red and black) 180 degrees out of phase to each other. So by taking one of the "hot" 110V lines relative to neutral (white), you get 110V. No transformer needed.

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  • jmengel commented on jmengel's instructable How to build a garage from the ground up7 months ago
    How to build a garage from the ground up

    The concrete takes a few days to do and then you need to let it cure a bit. Talk to the contractor on that, my guess is a week. For us in MN, the best time to build is in September since it is still warm, one of the driest months, and less bugs. If you have a slab with block and bolts for your sill plates, all the materials on-hand, a good set of plans, and a capable crew of 4-5 you could get the walls up, sheathed, windows in and the roof trussed and shingled in a weekend. After that, a day for electrical, a day for doors, and a day or two for siding. You could have a basic garage like mine done in a week. You only really need a crew for the walls and roof, I did the rest on my own on weekends and it took like 4 weekends or about 8-10 days of hard work.

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  • jmengel commented on jmengel's instructable Practical LED Lighting for Fun and Profit7 months ago
    Practical LED Lighting for Fun and Profit

    https://en.m.wikipedia.org/wiki/Luminous_efficacyYes, you are wrong. Thermodynamics is a cruel mistress.

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  • jmengel commented on jmengel's instructable Arduino home energy monitor shield7 months ago
    Arduino home energy monitor shield

    Have you seen it? Because I have, and no resistor divider is needed. I suggest you read the datasheet:http://www.ti.com.cn/cn/lit/ds/symlink/lm2575-n.pdf

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  • DIY Maglite LED upgrade conversion 5,000 lumen

    Fire, good! Have you done any testing on your heat sink performance installed in the maglite? How about luminous output over time (single cycle and multi-cycle)? With your stated 80 watts, and assuming that your drop in housing moves heat out of the LED's at 1 degrees C/W added to the LED die junction to solder pad resistance of 1.2 degrees C/W you are talking a 176C rise in die temperature within the engine before any heat transfer to the maglite housing. Since the maximum recommended junction temperature for these LEDs is 150C, and your instructable does not appear to suggest the application of a thermal compound to the engine drop in prior to installation into the maglite housing my guess is the luminous lifetime of such a light engine is limited. What can you tell us?

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  • jmengel commented on jmengel's instructable Arduino home energy monitor shield8 months ago
    Arduino home energy monitor shield

    You are going to have to read the Instructable. Hint, it is in "Step 3 Code".

    All of these variables serve to get from the measured values to a somewhat accurate calculated current, power, voltage value. The calibration code is essentially Trystan Lea's, and he has some explanation on his website: https://openenergymonitor.org/emon/buildingblocks/...https://openenergymonitor.org/emon/buildingblocks/...For calibration, I used a large resistive load of known magnitude, a 1500W electric space heater, to load the system and then tweaked the calibration values until the CTs and code reported good voltage, current, power and power factor for the load. Good luck!

    If you'd like to hire me to write the code for you at USD$150 per hour, then send me a private message. Otherwise you are going to have to DIY, it will do you good.

    LM7805 has the same 1A rating as the LM2575 and should work fine so go for it. Might need a TO-220 heatsink on the LM7805 but those are easy to get.

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