Welcome to the Cumulus Support forum.

Latest Cumulus MX release 3.16.1 (build 3183) - 06 May 2022

Legacy Cumulus 1 release v1.9.4 (build 1099) - 28 November 2014 (a patch is available for 1.9.4 build 1099 that extends the date range of drop-down menus to 2030)

Download the Software (Cumulus MX / Cumulus 1 and other related items) from the Wiki

If you are interested in supporting Cumulus then maybe you would like to contribute to the maintenance of the Wiki? This need not take hours of your time - just a half hour here and there can make a big difference, particularly if many people are doing this. Any contributions are very welcome, whether they involve new content or editing of existing content. It will be very helpful to current and future users of Cumulus software if the Wiki is kept well-maintained and current. If you are interested then please contact forum user saratogaWX and ask for a Wiki account.

Solar Sensor

Discussion specific to Fine Offset and similar rebadged weather stations
Post Reply
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Solar Sensor

Post by watsonm »

I have looked through the forum and found reference to version 3 of the Fine Offset Solar sensor and was wondering :

1) Is this the latest version?
2) Is the version number stamped on the unit so it can be specified when ordered.
3) can it be purchased without the transmitter?
4) Are they more reliable now as I believe v1 and v2 had various issues.
5) Can the solar panel be disconnected as I am using Lithium/Ion non rechargeable batteries and just want the sensor data

My system is a bit like "Triggers Broom" (BBC: Only Fools and Horses) having started out as a Maplin N96GY system. The only original item is the weather vane and rain bucket. The orginal did not have the solar pod but the new transmitter has 6 pins in the rain rj11 socket whereas my old transmitter only had 4. I do not use the console as I receive the 433Mhz signal using a SDR dongle on a Raspberry pi and some python software. I then create an Easyweather.dat file using some more python code.

So I would like to try and "upgrade " my setup if I can get hold of the Solar Pod and if it doesn't discharge the lithiums too quick!!! (and it's not too expensive :lol: )
Regards Mike

Image
AllyCat
Posts: 1108
Joined: Sat 26 Feb 2011 1:58 pm
Weather Station: Fine Offset 1080/1 & 3080
Operating System: Windows XP SP3
Location: SE London

Re: Solar Sensor

Post by AllyCat »

Hi,

The Fine Offset company now appears to have "morphed" into "Ecowitt" and I don't know if they are still manufacturing their original products; some "spares" are still available, but usually at a greatly inflated price. However, the Solar Pod is available at a very fair price (so the answer to 3. is Yes). That (very reputable) supplier has been selling (only) those Pods for some years now, so I doubt if they are "newly manufactured", but equally they are not the early version(s). But apart from all the early "issues", I've also experienced two more recent Pods that have failed, by transmitting "Overflow" Lux levels after a few years. Apparently some automatic internal "coarse scale factor" (attenuator) has a "weakness"; and personally, I've always considered the "UVI" measurement to be totally worthless.

The PV panel feeds a 3.3 volt regulator (to drive the internal electronics) and through a (Schottky) diode via the cable to the T/H/Wind Transmitter batteries. IMHO there's no need to disconnect the PV panel (but easy to do, by dismantling the Pod) since the 3.0 volts it delivers is insufficient to charge even the two "Rechargeable" Alkalines, and won't overload a Lithium type.

Beware that I once purchased a "spare" T/H/Wind transmitter Module which did have 6-pins in its Rain socket, but did NOT transmit the Pod data, so presumably not all are WH308x compatible. However, the Pod does have internal space for a pair of (NiMH) AAA cells and for a low-cost, off-the-shelf 433 MHz Transmitter module, so the Pod can be easily adapted to be an entirely self-supporting Solar Transmitter. Generally a better solution, as its not really a good idea to co-locate the Solar and T/H sensors, particularly with FO's ineffective "Stevenson" Screen.

Cheers, Alan.
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Re: Solar Sensor

Post by watsonm »

Thanks Alan,

I suspected that you would be the one to reply.. :roll:

I am using the Energiser Ultimate Lithium batteries so was a bit concerned about the solar panel as these are non rechargeable.

The pod will not be near the Temp transmitter as it is in a shaded place as per previous append discusssions but finding a 6p6C
RJ11 extension cable in the UK is proving a chanllenge as well. (just as well I like challenges..., may have to buy an RJ11 crimping tool)

I may take the plunge and give it a go.

Thanks again... Mike
Regards Mike

Image
AllyCat
Posts: 1108
Joined: Sat 26 Feb 2011 1:58 pm
Weather Station: Fine Offset 1080/1 & 3080
Operating System: Windows XP SP3
Location: SE London

Re: Solar Sensor

Post by AllyCat »

Hi,

If you decide to get the Pod, then first you can plug it directly into the Rain socket and see if it transmits. Note the rain switch is connected across the two middle pins so it can plug into either the Pod or the original T/H Rain socket. Also, all the encoding for the separate Solar Packet is done within the Pod (8 serial bytes IIRC, with a 60 second period, instead of the normal 48 seconds), only the 433 MHz RF transmitter hardware (and the battery) inside the T/H module is used.

If it works, then you will probably want to remove the "Stevenson Screen" (which is held captive by the plug) by cutting the cable or unsoldering inside the Pod. It may help to know that a 6-pin RJ11 is called RJ12 :) . Another of my favoured suppliers has some HERE but you may need to get a "Back-to-Back" adapter (or Female Coupler), or cut the cable and solder the wires within the Pod.

If your T/H/Rain transmitter doesn't accept the Solar data, then a 2 x AAA battery holder, two cells and a 433 MHz transmitter module (with a 16 cms length "piece of wire" antenna) will probably cost no more than an an RJ12 extension cable. :)

Cheers, Alan.
Last edited by AllyCat on Mon 11 Apr 2022 4:35 pm, edited 1 time in total.
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Re: Solar Sensor

Post by watsonm »

Thanks again Alan..... :clap:
Regards Mike

Image
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Re: Solar Sensor

Post by watsonm »

Hi Alan,

Received my Solar Pod but (surprise, surprise) cannot get it to send me any data. Tried it in both Transmitters (with 6pin RJ sockets.)
For info there is a label in the TX'r which says MO-4517M (which could be the testers ID.)

When the unit is in sunshine the small red led displays until I cover up the solar panel. If I leave it in the open sunshine the
red led stays lit but occassioanlly blinks every 5 or 6 seconds. Pressing and holding the reset button for tens seconds turns
it off until I release it.

I am guessing the data stream if it is sent is not being translated by the rtl_433 softare I have but wanted
to check if the led indicator shows it working or failing before I contact the seller.
Regards Mike

Image
AllyCat
Posts: 1108
Joined: Sat 26 Feb 2011 1:58 pm
Weather Station: Fine Offset 1080/1 & 3080
Operating System: Windows XP SP3
Location: SE London

Re: Solar Sensor

Post by AllyCat »

Hi,
AllyCat wrote: Mon 11 Apr 2022 1:23 pm Beware that I once purchased a "spare" T/H/Wind transmitter Module which did have 6-pins in its Rain socket, but did NOT transmit the Pod data, so presumably not all are WH308x compatible.
I strongly suspect that at some point FO "standardised" on the 6p6c socket in the T/H transmitters (to reduce their supply inventory), but not all support the Solar Pod. I have always warned about identification of these "spare" transmitters (in particular) because there are so many versions: Not only the three ISM frequencies (433, 868 and 915 MHz) and W/WO the Radio-Controlled Clock receiver hardware (that transmits a separate data packet), but some don't support the wind vane (and transmit a shorter, incompatible data packet) or maybe even a different vane (using Hall not Reed magnetic sensors), others not the Solar Pod, and at some time they appear to have reversed the Ground and "Pullup" pins on (IIRC) the "Wind" socket. The latter not an issue unless you were trying to "rationalise" the (Earth) cores in a CAT5 extension cable up to a Wind/Solar array on the roof (which I was). :(

The cable between the Solar Pod and the T/H Transmitter uses only 5 cores, but appears to perform a number of functions (in addition to simply looping-through the "Rain" signal from one RJ12 socket to the other). Firstly the Transmitter supplies power TO the Pod, which is essential when using the normal Consoles because the transmissions MUST continue (precisely every minute) overnight, since their Receiver is powered up only when a transmission is "expected" (to economise on Console battery consumption). Then it receives the fully-encoded Data signal (containing a different Address) from the Pod to "Repeat" via its transmitter hardware. The Pod LED should flash once every exactly 60 seconds (but NOT the Transmitter LED at this time).

I'm not clear how the Reset switch works, but it does appear to synchronise the Pod transmissions so that they are always "interleaved" between the T/H packets (i.e. they are always at least a few seconds apart) and don't ever "collide". That's a potential issue with a totally independent Pod (for which its PCB appears to have been designed), that is perhaps why FO never seems to have sold such a device.

The RJ12 connections are documented on the (Pod) PCB, so you should be able to "see" the 1-minute period "DATA" packet with a 'scope, Logic Analyser or even a Multimeter or LED); my suspicion is that it's not getting through to the T/H Transmitter hardware. If so, a "local" 433 MHz transmitter module is probably the simplest solution, but you will probably also need a battery power source (or a supercap) to give sufficient current to drive the transmitter (typically 25 mA for 100 ms).

Cheers, Alan.
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Re: Solar Sensor

Post by watsonm »

Alan,

Thanks again for your considered reply.

I think I am gong to have to go the route of the stand alone transmitter...
Regards Mike

Image
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Re: Solar Sensor

Post by watsonm »

I've put this image in the stickies but for reference I thought I would duplicate it here.

Back of Solar Pod board Hardware is Version 4 June 2012
You do not have the required permissions to view the files attached to this post.
Regards Mike

Image
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Re: Solar Sensor

Post by watsonm »

Alan,

Update on Solar pod. The led on the solar pod behaved sensibly when I connected a couple of alkaline batteries to it , having stripped it down 8-)

Did some tracing with a multimeter and found one of the contacts that pulsed with the Led. Connected this to the old (battery hungry) transmitter as a test and behold it works. My hiveMQ broker receives several data points:

uv_sensor id = 6
uv_status = ok
uv_index = 3
lux = 56146.1
wm = 82.20512

Not sure what wm is as the calcuation for watts per square meter gives 443 for this lux.

WIll buy one of the 3 pin transmitters to see if I can get this all self contained.

Thanks for your help.... Mike
Regards Mike

Image
AllyCat
Posts: 1108
Joined: Sat 26 Feb 2011 1:58 pm
Weather Station: Fine Offset 1080/1 & 3080
Operating System: Windows XP SP3
Location: SE London

Re: Solar Sensor

Post by AllyCat »

Hi,

Personally, I try to find a modern Synthesiser type Transmitter (with a crystal in a rectangular/oval package), in preference to the old SAW (Surface Acoustic Wave Filter) in a circular "TO5 style" Metal Can. But they don't seem as easy to find in UK now, except with expensive and/or slow shipping. Also, some SYN115 (6-pin Transmitter chip) and SYN480R (8-pin Receiver chip) modules appear to be mis-described :( . It can be worth searching for Transmitter/Receiver pairs, often at much the same price.

IIRC there was a report that one of the FO WH308x consoles made a serious error in its conversion of the W/m2 value from Lux, so maybe that got "copied". My own 3081 Consoles don't offer a w/m2 value, only Lux (which is a "plausible" value, at least until the high-level scaling fails). AFAIK, the (Solar) wireless protocol contains only an "address" (randomly generated at power-up), a 4-bit UV (i.e. Integer) value and a 22/24 bit field in units of 0.1 Lux !

Cheers, Alan.
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Re: Solar Sensor

Post by watsonm »

Having "googled"

wm is the number of watts per steridian which is defined as "the solid angle subtended at the centre of a unit sphere by a unit area on its surface."
which is something that fries my brain.

This has the conversion factor of 0.001464 when converting Lumen per square centimeter to watts per square centimeter at 555nM

(This conversion factor has been implied in several old posts in the forum where people have assumed they have a faulty solar sensor. It
results in a w/m2 reading which is 5 time lower than it should be. ( q.v viewtopic.php?t=6910&start=15 )

I'll stick with the 0.0079 conversion figure for Lumen per square metre (Lux) to watts per square metre. (which is what Cumulusmx is doing )
Regards Mike

Image
watsonm
Posts: 71
Joined: Sun 03 Jan 2016 3:39 pm
Weather Station: N96GY -but like Triggers Broom!!
Operating System: Raspberry Pi4 Vers:11 Bullseye
Location: Poundbury, Dorset

Re: Solar Sensor

Post by watsonm »

Bought these transmitters and the extra coil aerials (which were needed) and managed to get them to work OK with the solar pod.

https://www.amazon.co.uk/gp/product/B07 ... UTF8&psc=1
https://www.amazon.co.uk/gp/product/B07 ... UTF8&psc=1

Managed to install rechargeable batteries and the transmitter into the internal base of the pod which is now sited on our fence capturing the rays.

Used an old photo cell for garden lights to top up the batteries as it produced more power that the cell on the top of the pod (which fell off anyway!! Used a piece of a margarine lid cut to shape to cover the hole.) Currently on the fence support but soon to be attached to pole just under the pod.

For information:
The transmission signal information of this transmitter and the other FO transmitters are as follows.

FO TX1 : RSSI: -2.20 SNR:34.0 Located 9 metres from receiving aerial (temperature sensor in shady spot)
FO TX2 : RSSI: -0.20 SNR 35.0 Located 7 metres from aerial (wind speed and direction on fence to be moved to garage roof gable end)
Solar Pod: RSSI: -5.05 SNR:30.9 Located 4 meters from aerial (Solar Pod , south facing , near to house)
Regards Mike

Image
Post Reply