Firstly may i say thankyou for the excellent information on this forum and the articles in Silicon Chip Australia magazines.
I have constructed and currently bench testing/configuring a new weather station, all has gone well, however i noticed my wind direction never changed from ENE. I disassembled the wind vane and had suspicions that the wires were connected the wrong way around as the circuit board was marked GND and VDO, but the GND wire didnt go to the GND of the TX board. So i swapped those and this had me getting all different wind directions but none of them were accurate.
My sensors are Holman WS5029 from Bunnings Australia and i presumed they were fine offset, but looking at the circuit board i am not so sure now. Please see attached wind direction circuit board.
Unfortunately that is not a Fine Offset windvane board. The Fine Offset one has 8 reed switches and a number of resistors to produce an analog voltage depending on the wind direction. It also has an RJ11 socket on it for the anemometer to connect to.
Thanks, yes there is an RJ11 on the other side but I thought the board looked too complex for a fine offset.
(11-06-2015, 12:50)Stuarts Wrote: Unfortunately that is not a Fine Offset windvane board. The Fine Offset one has 8 reed switches and a number of resistors to produce an analog voltage depending on the wind direction. It also has an RJ11 socket on it for the anemometer to connect to.
(This post was last modified: 11-06-2015, 16:49 by AllyCat.)
Hi,
Yes indeed, that is certainly not the "normal" Fine Offset Vane PCB. BUT the external sensors hardware LOOKs like the FO external sensors and the PCB is exactly the same shape. So either this is a new FO design or "Holman" have decided to buy FO sensors (or their plastics housings) and fit their own PCB/components.
The PCB looks as if it might have 8 Hall-Effect (magnetic) sensors (little black blobs) in place of the familiar Reed switches of the normal FO Vane assembly and perhaps the large "blob" in the middle is a microcontroller. The original FO sensor gives only a variable resistance so requires only two wires, but anything using Hall effect switches (and/or a microcontroller) will also need supply rails (i.e. Ground and +Volts) in addition to a switch or "signal" wire (the second contact of a switch might be connected to ground or supply). From a photo we can only guess if the "output signal" is a varying voltage (analogue signal) or perhaps some form of data protocol (e.g. a serial data interface such as "RS232"). Do you have any electronics equipment and/or knowledge to "Reverse Engineer" that board? If so I may be able to offer a few hints.
Finally, it appears that the Black wire in the photo is not connected to anything, is this so ? Wires breaking off is a notorious problem when dismantling the FO Vane sensors.
(11-06-2015, 12:44)nparnold Wrote: My sensors are Holman WS5029 from Bunnings Australia and i presumed they were fine offset, but looking at the circuit board i am not so sure now. Please see attached wind direction circuit board.
Just by curiosity, what's the reference of the chip on the center of the board?
(11-06-2015, 16:45)AllyCat Wrote: From a photo we can only guess if the "output signal" is a varying voltage (analogue signal) or perhaps some form of data protocol (e.g. a serial data interface such as "RS232"). Do you have any electronics equipment and/or knowledge to "Reverse Engineer" that board? If so I may be able to offer a few hints.
Just guessing but I bet in an analog output, maybe not very different from the "regular" Fine Offset ones.
(This post was last modified: 12-06-2015, 00:09 by AllyCat.)
Hi,
Yes we really need more information. I've tried "enhancing" the photo but can see no sign of any part numbers on the central chip. But it's common for manufacturers to hide the identity of critical components, to reduce copying. So it would be helpful to have photos of the underside of the PCB, the magnet in the rotor, the exact connections of the 3 (or 4) wires in the cable and a description of any details not obvious in the photos..
But I do like a good detective problem so here are a few clues so far, which perhaps suggest that it's not a Fine Offset:
- The PCB is dated March 2011, so it would be surprising if it's not been seen before from such a "popular" manufacturer as FO.
- FO generally don't use plastic microcontroller packages but direct "Chip on Board" technology.
- As mentioned above, a "loop through" socket for the anemometer is not included. But FO normally aim for maximum "backwards compatibility" (e.g using the "Rain" socket for the "Solar Pod" on the WH-308x stations).
The legend on the PCB beside the cable connections says "VDD - DATA - WIND - GND", how are the Black (and Yellow ?) wires connected (at both ends)?
Finally, some more background technical detail (in case this is a FO development). The "old" FO stations used a Thermistor for the external temperature, which shared the input of an Analogue-Digital Converter with the Vane resistor (using two "Enable" pulses). The ADC used the resistance of the Vane/thermistor to define a time (delay) which was counted by the microcontroller to produce a digital value.
After some years, the thermistor was removed (so the vane had sole use of the ADC), with the temperature apparently being obtained in a direct serial data format (SPI Bus) from the (updated) Humidity sensor. IMHO it would be quite difficult for a microcontroller (on the Vane PCB) to emulate a variable resistance for the ADC in an unchanged External Transmitter. So I suspect it may be now a digital interface.
Just to clarify, the Wind Anemometer does connect through that board, the black wire looked like it had broken off because i soldered it to the other side and swapped it with the Yellow as a test. Sorry i have just put it all back together and im going to see if i can get my money back at Bunnings first. Yes i would certainly suspect its digital given that there is a chip in the middle. If i have no luck at returning it then ill take some more pictures. As you can see from their website, it looks just like a Fine offset, except that the rainfall unit is round. http://www.holmanindustries.com.au/produ...r-station/
I'm located in Trevallyn, so not far from you. I went around in circles for a while trying to find a local source for the FIne Offset stations. It looks like I just missed out on Jaycar having a run out special on a low end Fine Offset station. They carry one of the more upmarket ones, but at (IIRC) around $140, it was a bit expensive to buy and throw half of it away. I ended up ordering one from an Australian eBay vendor for $99 delivered, although it hasn't yet arrived.
Also the "Sun Shield" (which works rather poorly on the FO stations) looks slightly different. The "real" FO station (WH-3081) on that Holman webpage is this one. Did you buy a complete station or just a "spare part"?
Before (if) you return that Vane, please can you check the wire/colour connections at both ends of the cable. If it's Fine Offset compatible , I would expect the sequence of the pads on the PCB to NOT be the same as in the RJ11 plug, i.e. I think the WIND and GND should be on the two middle contacts with VCC and DATA on the two outer contacts of the plug.
That vane PCB is very interesting because several people have proposed (personal) projects to "improve" the FO Vane by replacing the Reed switches with Hall Effect sensors, and here it appears already to have been done comercially. It is well-known that the 8 "intermediate minor" directions (ENE, etc, when two reeds are supposed to close at the same time) occur much less frequently (i.e. for less than 22.5 degrees) than the "primary" directions. Personally, I'm working on two "projects" (unfortunately progressing very slowly) to improve this aspect of the FO Vane. One is a pure hardware addition, the other primarily a "software" solution.
It's a pity that I'm on the other side of the world because I have several FO Vanes (they only cost £10 , AU$20 as a spare part here) and would love to get my hands on yours to Reverse Engineer it.
