Page 2 of 2 FirstFirst 12
Results 11 to 18 of 18

Thread: Power Injection - Fuse blowing Explaination

  1. #11
    Join Date
    Dec 2012
    Location
    Hudson MA
    Posts
    3,188
    Post Thanks / Like

    Default Re: Power Injection - Fuse blowing Explaination

    Once you put a fuse in the line the keep v+ separate rules are again in effect.
    Last edited by MartinMueller2003; 11-17-2018 at 12:09 PM.


    2018 - Moving and going to visit my Daughter in New Zealand. Most likely I will be dark or nearly dark, Some static stuff that is simple to put up.

  2. #12
    Join Date
    Jan 2015
    Location
    Folsom, CA, USA
    Posts
    1,718
    Post Thanks / Like

    Default Re: Power Injection - Fuse blowing Explaination

    I'm not convinced Jerry theory is your full issue. The fuse time current curves should show the fuse can handle a inrush, and hold the speculative 6.5A for a few seconds, before popping. or is that what it is doing?

    Secondly, is your test starting full white at 100% = full 4.8A per 100 pixels?.

    I do like Jerry's idea of splitting loads: say; 100 Pixels, 100 Pixels and 70 Pixels, but your fuses are still undersized at 5A for a 4.8A load on the 100 pixel runs. Assuming you can't upsize to 6A due to the copper bus on the controller.....Consider reducing the brightness to help load on the fuses and avoid additional nuisance tripping, or bypass the controller power taps, and feed pixels (one 270 pixel string) directly from the power supply. Provide Data and Ground only from port one, and a Power supply tap 1-15A fuse feeding 3-15A wire size - one per power point. This should balance power needs over your 3 power point, without effecting injecting points. If jerry is right and power point 2 is plowing fuse 2, then pulling down 1 & 3....this design will fix that.
    In Lights Therapy

  3. #13
    Join Date
    Jan 2016
    Location
    Ashburn, VA
    Posts
    302
    Post Thanks / Like

    Default Re: Power Injection - Fuse blowing Explaination

    Quote Originally Posted by mrGrumpy View Post
    I'm not convinced Jerry theory is your full issue.
    HA! I'm not convinced that Jerry could pour P!$$ out of a boot if the instructions were on the heel.

    I agree. I'm spit-balling. But there does seem to be concurrence about separating the loads into individual fused circuits.

  4. #14
    Join Date
    Jan 2015
    Location
    Folsom, CA, USA
    Posts
    1,718
    Post Thanks / Like

    Default Re: Power Injection - Fuse blowing Explaination

    Quote Originally Posted by Jerry-Rigs View Post
    HA! I'm not convinced that Jerry could pour P!$$ out of a boot if the instructions were on the heel.

    I agree. I'm spit-balling. But there does seem to be concurrence about separating the loads into individual fused circuits.
    No..no..I think you nailed it, but feel there are more issues to the WHOLE problem than power point 2 having too much load....like under sized fuses.
    But I don't concur separate loads fixes the installation....too small fuse...need 6A minimum, but will the controller carry 6A
    The solution is one 15A fused circuit that connects to all 3 power points.
    In Lights Therapy

  5. Likes Jerry-Rigs liked this post
  6. #15
    Join Date
    Dec 2016
    Posts
    156
    Post Thanks / Like

    Default Re: Power Injection - Fuse blowing Explaination

    This design is guaranteed to blow all three fuses starting with fuse number two. You need to separate the v pluses at the injection site as Martin says when using fuses.

  7. #16
    Join Date
    Dec 2016
    Posts
    156
    Post Thanks / Like

    Default Re: Power Injection - Fuse blowing Explaination

    Quote Originally Posted by Smerk View Post
    This design is guaranteed to blow all three fuses starting with fuse number two. You need to separate the v pluses at the injection site as Martin says when using fuses.
    Using higher rated fuses may save you, but all three will still blow at once if there ever is and overdraw.

  8. #17
    Join Date
    Nov 2014
    Location
    Fox Valley Area, Wisconsin
    Posts
    122
    Post Thanks / Like

    Default Re: Power Injection - Fuse blowing Explaination

    Good point on multiple power supplies connected in parallel. They can start to argue between themselves and create all sorts of havoc.

    On multiple parallel supplies: DIODES! Dropping in one diode for every V+ to effectively isolate the power supplies stacked in tandem works. Yes, also compensate for the V-drop across the diode. Most power supplies are adjustable so they can handle 6.2v out and this in turn gives you 5v on the diode. I apply this method to 5v and 12v supplies. I do not see a need for this on the 24v, 30v and 36v in my installation, well, not YET!

    My display uses the least amount of 120v AC power around the yard. I have 3 central power supplies, lots of 4ga and 6ga SOW cord and power distribution boxes.

    So, for me, it is nothing to have a few 100A cords lying around.

    I would be more inclined to toss on the DC current clamp and get a peak reading. DC current clamps are not in everyone's toy box and usually allot more costly. One that I do have can do INRUSH. I work with DC in the field on motors when I am not having some fun making blinky/flashy @ home.

    LEDS - to my knowledge - do not have any sort of discernible inrush. That period of time needs an oscilloscope to capture a true reading. A properly sized fast-blow fuse would easily survive. I personally stay away from SLO-BLOW fuses - their only purpose is to protect devices with a reasonable inrush and that usually means motors or anything that has to come up to speed.

    Another thought is this: On average, fuses should be rated for 125% of load. I maximize fuses for this and design loads @ 80%.

    Confusing? Hang on ... it is easy. Using basics: 4 amp load, minimum fuse would be 5 amps @ 80%. Now consider fusing @ 125% which compensates for INRUSH and protecting the wire. So the basic 5 amp fuse @ 125% becomes 6.25 amps. This is not a standard size. Do not downsize but use the next available higher current fuse, which in ATO style, is 7.5 amps.

    The ATO fuse holders are also available with weather caps so they will tolerate wet conditions. I recommend using Permatex Tune-up grease on the contact surfaces. It is designed for electrical connectors, spark plug wires in general. It helps repel moisture and keeps contacts corrosion free. I have used it for the past 5+ years with excellent results. It also keeps my spark plug boots from getting stuck and self-destructing

    Those ATO fuses are designed for low voltage so they work quite well up to 36v is it? Please do not try to use these on 120v circuits as this exceeds their voltage rating.

    The bottom line: Avoid problems and always oversize the fuse so you can stay within basic electrical guidelines. These guidelines are available in the National Electrical Code and work very well for all the BLINKY/FLASHY lights too.

    I am pretty sure if you follow these guidelines, your fuse problem will go away. If not, then there is something wrong with the LEDS - could be one or two pixels causing problems. This would be something I have not encountered.

    Eddie
    -Eddie

    The missus wants to ride!

  9. #18
    Join Date
    Jun 2011
    Posts
    1,876
    Post Thanks / Like

    Default Re: Power Injection - Fuse blowing Explaination

    Quote Originally Posted by RGB_Mixer View Post
    Good point on multiple power supplies connected in parallel. They can start to argue between themselves and create all sorts of havoc.

    On multiple parallel supplies: DIODES! Dropping in one diode for every V+ to effectively isolate the power supplies stacked in tandem works. Yes, also compensate for the V-drop across the diode. Most power supplies are adjustable so they can handle 6.2v out and this in turn gives you 5v on the diode. I apply this method to 5v and 12v supplies. I do not see a need for this on the 24v, 30v and 36v in my installation, well, not YET!

    My display uses the least amount of 120v AC power around the yard. I have 3 central power supplies, lots of 4ga and 6ga SOW cord and power distribution boxes.

    So, for me, it is nothing to have a few 100A cords lying around.

    I would be more inclined to toss on the DC current clamp and get a peak reading. DC current clamps are not in everyone's toy box and usually allot more costly. One that I do have can do INRUSH. I work with DC in the field on motors when I am not having some fun making blinky/flashy @ home.

    LEDS - to my knowledge - do not have any sort of discernible inrush. That period of time needs an oscilloscope to capture a true reading. A properly sized fast-blow fuse would easily survive. I personally stay away from SLO-BLOW fuses - their only purpose is to protect devices with a reasonable inrush and that usually means motors or anything that has to come up to speed.

    Another thought is this: On average, fuses should be rated for 125% of load. I maximize fuses for this and design loads @ 80%.

    Confusing? Hang on ... it is easy. Using basics: 4 amp load, minimum fuse would be 5 amps @ 80%. Now consider fusing @ 125% which compensates for INRUSH and protecting the wire. So the basic 5 amp fuse @ 125% becomes 6.25 amps. This is not a standard size. Do not downsize but use the next available higher current fuse, which in ATO style, is 7.5 amps.

    The ATO fuse holders are also available with weather caps so they will tolerate wet conditions. I recommend using Permatex Tune-up grease on the contact surfaces. It is designed for electrical connectors, spark plug wires in general. It helps repel moisture and keeps contacts corrosion free. I have used it for the past 5+ years with excellent results. It also keeps my spark plug boots from getting stuck and self-destructing

    Those ATO fuses are designed for low voltage so they work quite well up to 36v is it? Please do not try to use these on 120v circuits as this exceeds their voltage rating.

    The bottom line: Avoid problems and always oversize the fuse so you can stay within basic electrical guidelines. These guidelines are available in the National Electrical Code and work very well for all the BLINKY/FLASHY lights too.

    I am pretty sure if you follow these guidelines, your fuse problem will go away. If not, then there is something wrong with the LEDS - could be one or two pixels causing problems. This would be something I have not encountered.

    Eddie
    Real curious as to where you think there is an "inrush"?

Page 2 of 2 FirstFirst 12

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •