OTGW and Orange Pi Zero one device.

This Forum is about the Opentherm gateway (OTGW) from Schelte

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cyril
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Re: OTGW and Orange Pi Zero one device.

Post by cyril »

texnic wrote:I've maybe a stupid question, please excuse my ignorance: why does this setup need a power supply, if OpenTherm provides the power from the boiler? Would it be possible to use that power?

Also, what do I connect to the 4 orange terminals? I currently have a single 2-wire cable running between an OpenTherm boiler and a Honeywell Round Modulation thermostat.
It is possible to use OpenTherm bus like power supply, but it additionaly load for bus.
Two terminals on right side - to connect the thermostat, left side - to connect the boiler.
texnic
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Re: OTGW and Orange Pi Zero one device.

Post by texnic »

cyril wrote: Yes. But you have to solder wire to connect RPi with board. Also you can buy OrangePI Zero, install Armbian or Openwrt, activate relay port and connect from RPi via ethernet or wifi.
I'd asked because I already have a RPi 3, so it would be simpler to try with it. If I buy your board, would you be able to explain the soldering thing?
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Re: OTGW and Orange Pi Zero one device.

Post by hvxl »

texnic wrote:Why does this setup need a power supply, if OpenTherm provides the power from the boiler? Would it be possible to use that power?
The Opentherm bus coming from the boiler can provide power, but a gateway must be able to deliver that same amount of power to the thermostat. That leaves nothing for the Orange Pi + Gateway to run on.

Even in the exceptional case that the boiler supports smart power and the thermostat only uses standard power, the device should in theory be able to extract at most 266 mW out of the bus. Even though an Orange Pi doesn't use a lot of power, 266 mW is simply not enough.
Schelte
texnic
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Re: OTGW and Orange Pi Zero one device.

Post by texnic »

Thanks Schelte, makes sense of course.
pdv
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Re: OTGW and Orange Pi Zero one device.

Post by pdv »

Hi Cyril,
Got your board and it works as explained. Thanks!
Small question. I assume that the you use a DS18B20 as Temperature sensor. Is that correct?
cyril
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Re: OTGW and Orange Pi Zero one device.

Post by cyril »

Yes. I am using ds18b20. It connects like this http://otgw.tclcode.com/peripherals.html Resistor 4k7 already included.
paulockenden
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Re: OTGW and Orange Pi Zero one device.

Post by paulockenden »

Hi Cyril,

I've just ordered one of your boards on eBay, but it hasn't arrived yet.

Have you had any problems with the Orange Pi Zero running hot? Is there room for a heatsink when using your board?

Thanks,

Paul.
texnic
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Re: OTGW and Orange Pi Zero one device.

Post by texnic »

paulockenden wrote:I've just ordered one of your boards on eBay, but it hasn't arrived yet.
Delivery from Moscow to NL took 14 days in my case.
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Re: OTGW and Orange Pi Zero one device.

Post by paulockenden »

Still waiting (not a problem - it's just international post).

But I just wanted to know whether to buy a heatsink for the Orange Pi Zero? Perhaps it isn't needed? Perhaps there's no room?

The board (OP0) does seem to get quite toasty.

P.
bruce_miranda
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Re: OTGW and Orange Pi Zero one device.

Post by bruce_miranda »

Paul, What have you measured the OP0 to run at?
paulockenden
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Re: OTGW and Orange Pi Zero one device.

Post by paulockenden »

About 30 degrees (in a cold room) when doing nothing, rising to 45 with some gentle tasks and 70-80 if you start to really push it. At that point I think the CPU throttles back a bit.

That's without a heatsink.

P.
bruce_miranda
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Re: OTGW and Orange Pi Zero one device.

Post by bruce_miranda »

Is that measured temperature or reported temperature. The reason I ask is there are reports that say that the reported temperatures are not accurate. I can't see the OTGW being CPU intensive, so may be worth derating the CPU in any case?
paulockenden
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Re: OTGW and Orange Pi Zero one device.

Post by paulockenden »

That's reported. I guess I should get the FLIR out....
cyril
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Re: OTGW and Orange Pi Zero one device.

Post by cyril »

Hi guys! About temperature. My OPIZ running under OpenWRT around one year with temperature around 80-90 degrees. Armbian has more efficient power management, so it colder with Armbian. Also I am using another Orange Pi board with same temperature around 3 or 4 year 24/7 and it working without problems. If one of this boards burns out, I let you know.
About shipping. Sometimes parcels reach destination quickly, sometimes it hangs up in one point during two weeks. Two of all boards returned without reason and I've shipped it one more time. So it can take long time, but will delivered at the end.
bruce_miranda
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Re: OTGW and Orange Pi Zero one device.

Post by bruce_miranda »

Once you load the OS image and get the Orange Pi connected to your network, how do you interact with the OT gateway? I'm guessing the OS on the Orange Pi is headless, so where is the OT Monitor loaded? I.e. how do view the data?
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