Posted: Monday Jun 13th, 2016 04:46 pm |
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chrisb
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Hi,
Is it possible to remotely locate a RLY02 module from the alarm panel?
I'm going to use the relay module to switch some 24v irrigation valves and I'd like to locate the relay module next to the 24v transformer on the outside of my house near the valves.
Can I run approx 12m of alarm cable from the comfort panel outputs to the relay board?
I'm not powering the relay outputs from the alarm panel, this will be a separate 24v transformer. The connection form the comfort panel will just control the relays,
Thanks
Chris
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Posted: Monday Jun 13th, 2016 06:15 pm |
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Ingo
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I am going to venture a guess here and say 12m would still be fine BUT if it's going to the outside of the house you might open your system up more for possible lightning damage but if you get a direct strike, or very near strike, the last thing to worry about would be the alarm panel. Give it a test, I am sure it will work.
The longer the runs the more prone to noise it will be even though it's RS485 which is quite robust. Also, if I remember correctly, the RLY02's are reed relays with a 500mA current limit. The sprinkler valve inrush currents can exceed that but only for a short while. I would rather use the RLY01's with a snubber circuit to be safe.
My 2cLast edited on Monday Jun 13th, 2016 06:17 pm by Ingo
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Posted: Monday Jun 13th, 2016 06:29 pm |
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slychiu
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I agree with Julian. RLY01 is more robust, also RLY02 ican only switch 30V maximum not 230V
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Posted: Monday Jun 13th, 2016 06:52 pm |
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chrisb
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Thanks for the replies.Just to check though :
The cable from the alarm panel to the relay module will be from the open collector outputs, not the RS485.
I've checked the valves and they have a 300mA inrush so should be in tolerance, and I'll be switching 24v through the relays.
Thanks.
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Posted: Monday Jun 13th, 2016 07:01 pm |
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slychiu
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That seems OK
However if the output is on, that means the transistor is turned on, it is susceptible to voltage surge, so it easy to damage
so try to shield or protect
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Posted: Monday Jun 13th, 2016 07:34 pm |
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Ingo
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Sorry, dunno where my mind was. You are right, it's connected to Outputs rather than RS485 like the iRIO relay board.
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Posted: Monday Jun 13th, 2016 07:59 pm |
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chrisb
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Great, thanks guys, I'll give it a try.
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Posted: Monday Jun 20th, 2016 06:01 pm |
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mikegriff
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Hi Chris
I would mount the relay board in the Comfort panel, and then use that to switch another relay board located outside with your 24v transformer.
It doubles the cost but protects your output board on the comfort unit.
it also makes fault finding much easier.
If you use a wall wart for the switching volts for the outdoor relays you can easily turn the system off by turning off the wall wart and you can fit some switches in parallel with the comfort relays to override the valves to be on.
Mike
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Posted: Friday Sep 16th, 2016 09:22 pm |
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CarloTruax
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Hi...as per my knowledge 12m would still be fine BUT if it's going to the outside of the house you might open your system up more for possible lightning damage but if you get a direct strike, or very near strike, the last thing to worry about would be the alarm panel. Give it a test, I am sure it will work.The longer the runs the more prone to noise it will be even though it's RS485 which is quite robust. Also, if I remember correctly, the RLY02's are reed relays with a 500mA current limit.
turnkey pcbLast edited on Saturday Mar 12th, 2022 05:51 pm by CarloTruax
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Posted: Saturday Sep 17th, 2016 06:34 am |
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slychiu
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The RLY02 reed relays are not as robust as the RLY01 which are mechanical relays, ie they have a much lower limit for voltage between open contacts and voltage from coil to contact
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