Jump to content


  • Posts

  • Joined

  • Last visited


10 Good

1 Follower

About n1ist

  • Birthday 05/01/1964

Profile Information

  • My favorite Christmas story
  • Location
    Malden MA
  • Biography
    I'm a hardware engineer interested in DMX controlled lighting
  • Interests
    Ham radio, blinking lights
  • Occupation
    hardware/software/embedded engineer
  • About my display
    Not much yet, but there's always next year
  1. According to the TI datasheet, the maximum emitter current (that's the sum of all the channels) is 2.5A worst case. They also spec maximum die temperature so that's the second limit on power dissipation. /mike
  2. Make sure you don't accidentally stick anything (a finger, a tool) in the open section of the breaker box where the breakers are missing. I'd even tape a cardboard or plastic cover over the big holes. It's way to easy to be killed or start a fire with what you have now. As for power, a 15A circuit can handle 1800W non-continuous or 1440W continuous load, so you are way under that with 800W per circuit. /mike
  3. Most of those are 14 or 16 volt bulbs, and are wired in series. Remember the old light strings - if one goes out, they all do. Unlike the modern dollar-store bulbs, the entire milk-glass envalope is the bulb. More modern ones are plastic shells that fit over a bulb. /mike
  4. My guess is that you are pulling too much current with your strings. You would need to change the triac to one with a higher rating and may need to heat simk it. /mike
  5. If you hardwire together molds, you won't be able to separate them for storage or to use them in different places in the future. /mike
  6. Do not make a double-male (suicide) cord. It's illegal and can be deadly. Why not run an extension cord up the tree from where the lights should plug in to where the plug is now? /mike
  7. PIR depends on a roughly body temperature thing moving in the field of view. Ultrasonic or beam-break may be better in this case. /mike
  8. For safety, you MUST have a transformer in your power supply to isolate the lights from the AC line. Omitting the transformer can leave you with a lethal situation. /mike
  9. I'd try orange or white with brown caps or tinting. Running at lower voltage may shift the orange enough. /mike
  10. It's a pushbutton (or more commonly two, one for each hand) that needs to be continuously pressed to allow the effect to be fired. A person with direct view of the entire area would hold down the buttons during the show; if at any time he thinks there's a safety issue (someone or something in the area, a malfunction, etc.), he would let go of the button and the effect would not fire. Name comes from the early days of trains; if the engineer was injured or died, he would stop holding the deadman and the train would stop. As for how it's wired, that depends on the unit. Ideally, it would be in series with the solenoid that releases the gas. /mike
  11. They have one of these in the discovery room at the Boston Museum of Science. I think they used fluorescent tubes rather than incandescents with a diffuser panel. You could also look at the white LED flex tapes on eBay. 1400W in an enclosed box with plastic sounds like something will end up melting. /mike I just did a quick Google search and found these plans
  12. The DMX specification states that DMX should NOT be used to control pyro or automation as it has no error-detection or error-correction in the protocol. I would not use it unless there is an additional deadman switch controlled by someone with a clear view of the area at all times. /mike
  13. It depends on what you are using them for. If they are for ethernet or RS485 (DMX, Renard, Pixelnet), then it does matter - at least that you get the twisted pairs in the right place (1&2, 3&6, 4&5, 1&8). For DC applications (controlling SSRs, spotlights, etc), then it doesn't matter as long as the pins are connected straight thru (1-1, 2-2, 3-3, etc) /mike
  14. Your picture doesn't quite show the connections on the switch. It should be like this, which will guarantee that the male plug is either totally isolated or feeding the floodlight. /mike
  15. Please note that having an energized male plug is both a NEC violation and a safety hazard. This includes one with a connected neutral as the neutral (being a current-carrying conductor) is not at ground potential, and if it is ever broken after the male plug, would be at full line voltage. You could connect a pigtail outlet to the photocell and a male cord to the floodlight and tuck it into the box; Just unplug the floodlight from the photocell and run an extension to your LOR. It would still be a code violation (use of flexible cord for permanent wiring, and no breaker or fuse on permanent wiring fed by a male plug) but at least it wouldn't be a shock or fire hazard. The code compliant way would be to mount a flanged inlet (basically a panel-mount male plug) and use a DPDT switch to switch both the hot and neutral wires of the floodlight to either the inlet or the photocell. In both of these cases, ground for the incoming wiring, pigtail or inlet, outgoing wiring to the floodlight, and the box itself should all be common. /mike
  • Create New...