Designing a system for controlling the lights at a private airfield

Discussion in 'The Projects Forum' started by Rabbit H, Apr 30, 2018.

  1. KeepItSimpleStupid

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    Mar 4, 2014
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    I still think the smart relay will be your best bet. Before even doing anything, idec has a simulator. I does require a small "development kit".

    I think idec is just drawing wires. No real programming at all.

    Teco is another: http://www.factorymation.com/SG2_PLR_Smart_Relay

    Schneider electric has Zelio: https://www.schneider-electric.com/en/product-range/531-smart-relay---zelio-logic-sr2-sr3/

    You can always do what i do when designing something, especially programming, and I've been told it's good one. it's generally not understood by management.

    I tend to think in term of:
    1) I have infinite resources
    2) What would I like it to do.
    3) What do I need it to do.
    4) What do I need it to do now.

    You can totally save redesigning, if you plan properly. It sometimes cost you very little money to anticipate a feature. You plan for it, but don't figure all of the costs. it might require a bigger case or a bigger power supply.

    Let's say here you wanted accounting: It might be as simple as how many times was it used and when. Maybe you would like a webpage?
    Ethernet? Modbus?

    Right now, I'm thinking about designing a lamp controller. A 6100 Lumen dimmable LED lamp. There is Android app, hardwired and RF.
    RF means no metal box for the controller. It can't be android. Oddly enough, I find having a LED on the handheld control so the control can be located, I find important. The problems I ran into is that no one knows what they are talking about. There are 0-10V dimmers and 1-10 V dimmers. The 0-10 V dimmers where less that 0.67V is considered off. The company says that a 0-10V dimmer is included. It's really a 1-10 V dimmer that they are including which can use PWM, resistance and 1-10V. Each one has issues.

    The locater LED is planned to be a dual state LED which is 100% bright when the dimming slide switch is past a detent and some other brightness otherwise. I am cannibalizing a commercial dimmer. Three options are floating around in my head and one requires building a PCB. 1) Build a PCB and connect via a modular phone cord jack. 2) Use the 120 VAC built-in switch and piggyback a hard-wired wired phone cord and 3) Use another 0-10V dimmer and do the same, just no 120 VAC to switch.

    #1: I don't know if it can be done with 6 conductors. I don't think the housing will support 8.
    #2 and #3: should be do-able with 6 conductors. They are radically different because the 0-10 (#3) dimmer comes with an aux power supply and won;t require a relay.

    The 1-10 V dimmer would have to switch 120 V. It can use a 10K pot and resistance dimming. #2 might be more reliable with a 1K POT because 10 mA wets a contact better than 1 mA. I may have bought the 10K POT prematurely.
     
  2. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    Huh?

    Harvey
     
  3. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    Crutschow,

    Sorry for the delay in getting back to you. We've had a lot of rain here recently and that always means limited bandwidth due to fire ants invading the neighborhood BD cans. AT&T says it's going to be a week before they can get to us but it looks like the wires have dried out a little today because I've got SOME connectivity back. For now anyway!

    To answer your question about what kinds of time delay relays I'm considering, please see the following...

    [​IMG]
    This type of TDR is "HVAC Quality" but looks like it could work. They typically come in delayed-on or delayed-off modes with quite a range of timings available. They usually run between $15 and $30 and considering how few I've changed in my air conditioner over the years, their reliability is quite good. However, being designed for HVAC use, I doubt that their precision is top notch. (Not that my application has to meet NASA specs!)

    [​IMG]
    This type is more "electronic quality" and is probably a lot more precise than the "HVAC" relay but it comes with an elevated price tag ($85-$115)! I suspect that it is as reliable as the HVAC relay. However, besides the common delayed-on and delayed-off modes, it comes in interval, "one-shot", and "cycle modes".

    Harvey
     
  4. KeepItSimpleStupid

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  5. crutschow

    Expert

    Mar 14, 2008
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    Unfortunately the images aren't visible to me.
    How did you try to post them?
    You can use cut and paste, or the Upload a File at the bottom of the post.
     
  6. crutschow

    Expert

    Mar 14, 2008
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    And what the heck does that mean? o_O
    I agree with Rabbit, post #41 deserves at least one "huh?".
    It doesn't seem to live up to your KISS moniker. ;)
     
    Last edited: Jul 9, 2018
  7. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    Well, AT&T just left and so I'm back online until the next thunderstorm!

    KISS, I wasn't dissing you (and I don't think Crutschow was either) but your explanation of your design process in post #41 was way over my head. That said, I suspect that we all have similar design processes that are simple and logical to us but would undoubtedly appear over-the-top if we tried to explain them to someone else in writing. :)

    I DID follow the links you provided for the Smart Relay and its programming software and while it appears to be a very versatile and useful device, it seems to be quite a bit more complicated than what I'm looking for. (Remember, I'm the guy whose VCR flashed 12:00 throughout the 1990s!)

    * * * * * * * * *

    Crutschow,

    I tried reloading the images of the two time delay relay types that I'm thinking of using but they're still coming out too small to make out. It's probably ME (see the 12:00 excuse above :( ) but I'll try again after lunch.

    Harvey
     
    Last edited: Jul 11, 2018
    KeepItSimpleStupid likes this.
  8. crutschow

    Expert

    Mar 14, 2008
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    Exactly how are you trying to upload the pictures?
    Have you tried a cut and paste?
     
  9. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    I've tried several different ways but I must be doing something wrong.

    Harvey
     
  10. KeepItSimpleStupid

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    Under account/preferences make sure

    [ ] Use the Flash-based uploader to upload attachments

    is unchecked

    Make sure the extension is in lower case i.e. .jpg or .jpeg
     
  11. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    KISS,
    I keep getting this message whenever I try to post an attachment:

    All About Circuits - Error

    You do not have permission to view this page or perform this action.

    I checked my account settings and found that the Flash-based uploader was checked, which I unchecked but it didn't solve the problem. I also checked my attachment's extensions and found that they were already lower case. However, they're .png, not jpg. Is that a problem and if so, how do I change it to .jpg?

    Thanks for your help,

    Harvey
     
    Last edited: Jul 12, 2018
  12. crutschow

    Expert

    Mar 14, 2008
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    No.
    .png are fine are and are preferred over .jpg for graphics files.

    Can you do a screen grab, such as using the Windows Snipping Tool, and paste that into your post?
     
    Last edited: Jul 12, 2018
  13. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    Crutschow,

    Snipping worked! These two images are of the two different types (not necessarily specific manufacturers or delay modes) of TDRs that I'm considering.

    The Dayton TDR is "HVAC Quality" but looks like it could work. They typically come in delayed-on or delayed-off modes with quite a range of timings available. They usually run between $15 and $30 and considering how few I've changed in my air conditioner over the years, their reliability is quite good. However, being designed for HVAC use, I doubt that their precision is top notch. (Not that my application has to meet NASA specs!)

    The Macromatic type is more "electronic quality" and is probably a lot more precise than the "HVAC" relay but it comes with an elevated price tag ($85-$115)! I suspect that it is as reliable as the HVAC relay. However, besides the common delayed-on and delayed-off modes, it comes in interval, "one-shot", and "cycle modes". I DO like the plug-in octal base which would make maintenance easier.

    Harvey

    Dayton TDR.PNG Macromatic TDR.PNG
     
    Last edited: Jul 11, 2018
  14. crutschow

    Expert

    Mar 14, 2008
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    The Dayton precision may not (or may be) as good as the Macromatic, but I suspect the repeatability will be sufficient for your needs.

    Maintenance is a consideration, but if you use crimp, push-on terminals (such as below) for all the connections on the Dayton it will be fairly easy to replace the relay, although not as fast as the octal connector obviously.

    So I don't think I'd pay the extra for the Macromatic unless you need one of its functions that the Dayton can't do.
    upload_2018-7-11_21-45-52.png
     
  15. KeepItSimpleStupid

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    Mar 4, 2014
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    There is a construction technique for building control systems which uses an enclosure with usually a 1/4" aluminum panel in the back, DIN rail (TS32), and wire duct. See here https://www.shutterstock.com/search/plc for some examples.

    You generally fasten the rail to the backer plate with machine screws and tapped holes. The amount of holes needed is minimal.

    It's basically an erector set for control systems. Generally all of the stuff is re-useable.

    Look around here: https://www.winford.com/products/cat_din.php

    Relays can be had that;s DIN rail mountable.

    Here https://www.asi-ez.com/member/x450-Phoenix-Contact-Equivalent-DIN-Terminal-Blocks.asp is another place to look around. Sometimes it's hard to order just a few terminals.

    The panels I built use 18AWG wire with low stranding e.g. 6/32 so the wire is stranded but stiff. Ferrules https://www.asi-ez.com/member/x450-Phoenix-Contact-Equivalent-DIN-Terminal-Blocks.asp are sometimes needed so screws don;t separate the strands.

    There's screw terminals and push terminal blocks.
    You need and end stop, then terminals, and then and cover plate and and another stop. The blocks have one end exposed and thus the last one needs a cover. You can use multiple end covers to separate terminals. Generally, I used two level terminal blocks. You can buy bus kist to bus a group of terminals together. e.g. Line and neutrals. The ground block is yel/green and is special.

    The one "trick" is to keep the low voltage separated from the high voltage stuff and to have blocks for the I/O.
    So, if you were taking 24 VDC to run three separate coils outside of the control, then have terminations for the coil. Don;t terminate one lead in the middle of the enclosure and another 10" away for this external relay coil.

    You can get fuseholders, circuit breakers and even convienience outlets that mount on the rail.

    Wires to the hinged front panel if needed take a little more finesse.

    24 VDC is probably the power source you want.

    I used Idec LED lights which can be labeled with either black on clear label maker or transparency film and a laser printer.

    One rule I used for myself is when I used multiple enclosures in different rooms, panel lights had to go to a $20.00 relay first. These were very thin. I didn't want it to be easy to blow a fuse in a panel in another room 100' away. The remote panel would go directly to a small DIN relay such as these: https://www.alliedelec.com/phoenix-contact-2966210/70207756/ and interface to the local panel via a contact closure.
    The relays I used worked on 24 VAC and 24 VDC. So now, the interface was a contact closure.

    My first panel was built in the 1980's and I used 24 VAC as my power source. As the system expanded, I found the need for a 24 VDC supply too.
     
  16. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    Actually, KISS, I am quite familiar with the modular DIN system (or at least I was some 30 years ago) from when I designed and built VFD motor control systems back in the late 1980s. The DIN system makes for a very tidy and versatile construction method that is easy to build, modify, and troubleshoot but its drawback is that it requires quite a bit of space, usually in the form of increased enclosure area/footprint.

    Harvey
     
    Last edited: Jul 13, 2018
  17. KeepItSimpleStupid

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    Cool. Not having any exposure was really tough. When I built by first, I had no exposure whatsoever. Wire ferrules were foreign and I didn;t use them. The lower stranding was foreign too.

    the design was relatively simple and was based on an "alarm system" type model. Octal based 3PDT relays with the diagram on the top. I had no idea about test buttons and indicators at the time either. One contact was the "latch loop". Another contact was the "indicator loop" and a third contact was the "alarm loop" for about 8 things. A momentary contact closure "turned on the alarm". Actually, no noise was made, but the system shut off about 8 gas valves at the cylinder.

    So, this "Safety panel" enabled up to 8-10 Hazardous gases (each selected by a switch); It enabled one or 2 reactors; it latched the alarm.

    Power was a "key switch" plus an on off push buttons. Reset from an alarm required moving the key switch from on to off to on and depressing the on push button. There were 2 panic buttons at the exit doors.

    So, pretty simple. I did not know about "monitored contacts" which is one deficiency in the system. A "monitored contact" has a resistor across the contact. Most of the contacts were in the room.

    The contact closure from the "fire alarm" was ersatz monitored. I placed a LED next to the latched indicator. When the LED was off, the fire alarm contact was closed. Thus, we knew when our panel could be reset. I think at a later upgrade, i did the same for the Hydrogen and Toxic gas alarms which were in a different room.

    For another system that was more "highly integrated" with a PLC, a separate safety PLC was used. It had to interface to my "gas control" panel.
    That had a PLC and a UPS. It was necessary to keep a purge running after an orderly shutdown. I think, hydrogen and toxic gas were indicated separately on the panel I built. The local panel had to know if the system was enabled.

    Adding another system was an extensive upgrade which required moving the gas detection equipment. It used sampling tubes an it now penetrated a fire wall. More panic stations more strobes.

    I didn't indicate panic. No monitored contacts. No "trouble alarm". The "fire alarm" contacts could be easily disconnected.

    Wiring was Teflon (PTFE) insulated fire alarm cable.





    https://www.alliedelec.com/macromatic-te-8816u/70819839/
     
  18. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    KISS,

    With all due respect, I'm pretty sure we're not talking about the same thing. I'm trying to come up with a simple timing circuit to control an airport's rotating beacon; whereas you're discussing alarms for monitoring hazardous gasses.

    Harvey
     
  19. KeepItSimpleStupid

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    "Asides" keep the board interesting. It's not totally unrelated. I can go crawl under a rock if you'd like?
     
  20. Rabbit H

    Thread Starter Member

    Aug 5, 2016
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    No, of course not! But I WOULD like to stay on track at least until I can make some progress on my little timing circuit.

    Harvey
     
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