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Jeff Messer

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WT,

 

Like klb says above check your sequence real good if it happens about the same time on a song. My problem was popping many channels on all over the network.

 

Jeff

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I'm going to jump into this mess.... why ? because RS485 was / still is a strong point of mine.

 

First off,  is your network (any one complete segment) a daisy-chain, OR, is is "Yed" and cables running all over the place ?

 

2nd, are you using a 120 ohm resistor at the 2 far ends of any total network ?

 

If you answer no to any of the above questions, then there is your problem.

 

My network is over 1300 feet long, and I have no problems, (That is NOT a typo.... 1300 is the correct number).

 

I have everything point to point, one in, one out of each controller, the ear end (G3 has a balancing resistor, and the last controller in the line has another.

 

Pc150003_zps17811f7d.jpg

 

PC150004_zps337ddfcd.jpg

 

and with hotglue for weather-proofing

PC150005_zps3e92a203.jpg

 

They work at getting the network "Clean" and no comm problems.......

 

Greg

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Not really a mess but had two major issues with data this year. I created the first problem and bad connection on the rj45. Its one network from the dongle all the way around 800 feet to last controller. Its a daisy chain..... Been running the show for 7 years and first year with this much trouble.

 

Jeff

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I am pretty sure I do not have a channel configuration problem. The sequences run fine other than a few problem areas as mentioned, unless there is something I am not understanding. I am starting to think its cable or the adapter. I have a different show after Christmas, and I noticed a slow down and brief shut down during one part of a song, because all channels are used and fast moving on off. I do have cabling everywhere and network cabling could be very close to power cables and others. Didn't know that could be a problem. I have a smaller display, so I am only using about 150 feet between the 7 controllers all daisy chained. Next year I will be much more methodical, plus next year's design will be easier to separate network and power cables. My problem is not huge. I am probably the only person that knows the lights are doing what I didn't intend. I was thinking copying and pasting from shared sequences could be some of the problem. Seems the ones I did from scratch doesn't have the issue. I don't know, my second year. Thanks everyone.

 

I have never seen nor heard of anything that a31ford did before. You say you did that to keep your network clean? How much you charge to do me a couple for next year???

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When I say "Clean" I'm referring to the data that is flying up and down the network cable.

 

RS-485 (what LOR uses for communication) is a very robust transmission system, and in most cases will work fine without the terminators I speak of. HOWEVER, as the network gets longer and/or faster, simple issues become random problems.

 

"Best Practice" is to run terminators no matter what, But as an example, a simple short cable to an ELL should not need terminators, or should it ?

 

In the real world we know that things can be strange, and with that said, it is still "best practice" even on a short network cable like that, issues can cause random problems.

 

I can make you a set of terminators if you supply a short network cable and a pair of female ends, but the cost of shipping would be insane to my side of the 49th.

 

Find an electronics buddy near-by (or the local high-school electronics teacher, they can make a small student project out of it). and show him/her the pictures above, and tell them, you need 2 units. The middle pair (blue pair) needs the 120 ohm 1/4 watt resistor.

 

I made them into a short stub, so I could get them into the controller boxes without breaking the network jack on the board. they can be slightly longer ( a foot or so) without  any issues

 

Greg

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I think when LOR tested early on, they found that in nearly all cases, termination made no difference, and it made things worse as often as it made them better.

I've run some long networks as well. With several conduit runs over 300 feet just to travel 30 feet at the surface. I never have run with terminators. The first time I had a com issue, I tied it back to a rs485 chip that had failed into transmit mode all the time. (It prevented anything past it from getting a reliable signal) Changing out the chip fixed it. The second time was a RJ45 jack that didn't look that badly damaged.

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I'll toss in a thought here since I use to run RS485 in a lab along with TCPIP at GB speeds via fiber, RS232 lines and so on. RS485 worked very well but I was using actual dual twisted pair, individually shielded, then overall shielded cable from Belden. Of course the lab was paying for the cable. Suprisingly, it worked very well with no errors to and from the devices attached and yes, the lines were terminated as required for RS485. The longest run I did was probably about '400 or so. Now I wasn't using RJ45 connectors, rather a Matrix connector/pins which are costly. I'm thinking that LOR uses the best wiring products that will work for "us", that are not as expensive as other methods, based upon the "average" user's needs. This keeps the cost down for us and makes their products easier to work with, again, for "us".

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klb, even though I agree Cat 5 is not what I would call the best cable for RS-485. And then LOR also runs a 9VDC supply that might see some minor pulsing, might as I say. We have to agree the smaller wire will have higher series resistance. And I would first start off sans terminating resistors. BUT! If I was to start seeing strange things happening. I would slap a terminating resistor in at the ends in a heart beat as a13ford is suggesting. Really cheap and rather simple device to make and install.

 

a13ford. Question for your install. Ok, so you put one at the far end of the daisy chain / controller. What I am not sure is the second terminator. Are you installing this at the first controller with cat 5 cable going back to the USB adapter. Or are you installed the second terminator at the output of the USB  adapter? I was always told that you want the terminators at the ends, very ends. Best that the RS-485 adapter should have the terminator resistor built into it. Interesting that this works at the first controller if that is what you are doing. What ever it takes, right?  ;)

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Yes, Do I just put one on the end of the daisy chain? Waiting to see answers to Max's questions. The show ran flawless last night and today so far.

 

Jeff

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Hi Guys, one is the far end (last controller) the other is in the G3 Mp3 network jack or the RS485 converter on the computer.

 

I actually have an extra cable on the far controller and have the terminator on the far end of that cable (I use it on the LT in the truck to test) as I cannot see the display from the house, hopefully I can get a set of ELL's for net year, and simply move the one ELL as needed to the truck when testing.

 

Greg

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  • 2 weeks later...

Hi Guys, one is the far end (last controller) the other is in the G3 Mp3 network jack or the RS485 converter on the computer.

 

I actually have an extra cable on the far controller and have the terminator on the far end of that cable (I use it on the LT in the truck to test) as I cannot see the display from the house, hopefully I can get a set of ELL's for net year, and simply move the one ELL as needed to the truck when testing.

 

Greg

 

Ok I understand the far end and can handle that one but unsure what you are talking about at the computer end. Are you saying out of the 485 adapter is the termination and then plug the network cable into it? 

 

Jeff

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.

Correct,  one terminator at EACH "END" of the cabling.

 

 

 

the Total impedence of the cable should be 60 ohms (120 ohms at each end = 60 total).

 

Greg

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  • 3 weeks later...

That was great help and will have a couple on hand this year. I did see picture on the forum where a Y-cables was made incase you messed up a 45 jack in the controller. I am unable to find that picture again. Any help?

 

Jeff

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