WMR200 Weather Station
Towards the end of last year I wrote a three part post about my new Oregon Scientific WMR88 weather station (part 1, part 2, part 3). While the installation was successful the setup was not completely reliable. I concluded the final post stating:
“If I am serious about logging and publishing my weather station’s data I will have to invest in some better kit to minimise gaps in the data. I have my eye on the WMR200 and may purchase one next year. The WMR200 has a built in data logger and a hefty looking external antenna which unlike the WMR88′s internal antenna I can, if necessary, modify. Also it should be possible to use the same suite of sensors simultaneously for the WMR200 and my existing WMR88 base station. This means that I can have two operational weather consoles and a set of spare sensors.”
Six months ago I did exactly that and purchased an Oregon Scientific WMR200. The idea was to compliment, rather than replace, my existing setup. This post details my experiences with this new weather station. Note that in this post I tend to compare the WMR200 with the WMR88 so you may want to read my original posts on that first.
The WMR200 currently retails for £400. However, Amazon, Weather Shop UK and Oregon Scientific themselves tend to offer the unit at up to £120 cheaper from time to time. It pays to be patient and wait for such a deal rather than pay full whack. I ordered directly from Oregon as they had the cheapest price at the time.
When the WMR200 arrived the most striking thing about it was how much bigger it was boxed than the WMR88:
Then again you get a lot more with the WMR200 to help justify the extra cost. Pictured below are most of the package’s contents:
- PCR800 Rain Gauge with rain filter
- THGN801 Temperature and Humidity Sensor
- WGR800 Wind Sensor (Anemometer & Wind Vane)
- STC800 Solar Panel
- USB Cable for connecting the base station to a PC
- Batteries for all sensors and the base station
- A mounting pole in three sections, base, rope, fasteners and stakes for ground mounting
- Cable ties
- Various brackets U-bolts and screws to allow for other mounting options
The remaining contents are the WMR200 base station itself and its power adapter which are shown below:
The included kit allows for a lot of flexibility as to how the sensors are installed, more so than the cheaper WMR88. All sensors bar the rain sensor can be placed together in a single array using either the supplied pole or an pre-existing one. Alternatively sensors can be distributed across separate locations using the supplied brackets. For example, attached to fences or buildings. The supplied pole which, in combination with the supplied ropes, fasteners and stakes allow for the option of a ground mounting which gives substantial height to the sensors.
I had already installed a mounting pole for the WMR88′s wind sensor so used it and the supplied brackets to install the wind sensor (pictured top), solar panel (pictured bottom right) and temperature/humidity sensor (pictured bottom left) together in the same location:
The WGR800 wind sensor supplied with the WMR200 is the same as the one that comes with the WMR88. The curious thing is that the WMR88 manual states that its wind sensor transmits a signal every 56 seconds while the WMR200 manual says signal transmission occurs every 14 seconds. Certainly each station updates their displayed wind readings at the stated intervals. Clearly the longer display interval on the WMR88 base station is a limitation of the base station rather than the wind sensor which transmits more frequently.
The THGN801 temperature/humidity sensor that comes with the WMR200 is shielded unlike the THGN800 that came with the WMR88 (I had built a shielded housing for the THGN800 which I can now decommission). While the THGN800 had clearly been superseded it was not completely obsolete. I simply changed its broadcast channel from 1 to 3 and moved it into a room in the house so I could see readings from there (as detailed here I had already installed a THGR810 sensor on channel 2).
The STC800 solar panel is a nice addition as it helps to power the WGR800 and THGN801 and will hopefully save on replacement batteries. It has two cables attached to it which can be plugged into each of the aforementioned sensors. The connections look to be well insulated and the supplied cable ties can be used to attach the power cables firmly to the sensor brackets.
I had no cause to replace or move the existing rain gauge as the same rain sensor is supplied with the WMR88 and WMR200: the PCR800. The bonus with the WMR200 is that you get a rain filter in the form of a fine metal grille to place in the gauge to catch debris. I have placed this in my existing PCR800. See my previous post for details of the PCR800′s mounting on the side of my shed.
In summary my current sensor setup now comprises:
- THGN801 for outside temperature/humidity
- WGR800 anemometer & wind vane
- STC800 solar panel to help power the THGN810 and WGR800
- PCR800 rain gauge
- THGR810 for temperature/humidity in the garage
- THGN800 for temperature/humidity in the house (placed in a different room from either base station to compliment their readings)
All of the sensors now in place are compatible with both the WMR88 and WMR200 base stations. As the sensors simply broadcast both base stations can receive data from all of the sensors.
This hybrid setup has also provided me with unused backup sensors for both wind (WGR800) and rain (PCR800). Given the extortionate cost of replacement sensors these are handy items to have in case of failure in one of the original sensors.
Base Station Installation
The WMR200 base station is a super-charged version of the WMR88 capable of doing everything the cheaper unit can do and more. First I will cover the similarities between the two before looking at the differences.
Like the WMR88 the WMR200 functions as an internal temperature and humidity sensor and as an air pressure sensor. The WMR200 has an optionally backlit LCD display similar to the WMR88. The WMR200 also features the same clock synchronisation feature as the WMR88. Both units can be powered from the mains and be loaded with backup batteries.
The WMR200 displays the same information as the WMR88 (temperature, dew point, humidity, wind, rain, pressure, UV, historical highs and lows, forecast, moon phase and current time) but its larger screen means that it can display more of this information at the same time. For example, the WMR88 can only display one set of temperature and humidity readings at a time while the WMR200 can display the internal base station readings and the readings from a selected channel simultaneously. The WMR200 can also display rain, UV and atmospheric pressure readings at the same time while with the WMR88 you have to cycle between the values. This makes it possible to review the current conditions at a single glance.
The WMR200′s screen features a resistive touch screen rather than the physical buttons of the WMR88. This makes the operations of cycling between sensors, checking highs and lows, etc far more intuitive. Unfortunately the WMR200 has preserved the WMR88′s annoying feature of beeping whenever the touch screen is pressed. This again cannot be switched off.
The WMR200 also functions as a data logger. However, Oregon Scientific’s included software remains as useless as ever so accessing the stored data is nigh on impossible. This is not an issue for me as I now use an external data logger connected via USB (more on that in a future post).
The WMR200 supports up to 10 channels and therefore up to that number of temperature/humidity sensors while WMR88 only supports 3 channels.
Below is a picture of the base station mounted to a wall (easily accomplished as there are mount points on the back):
The final advantage of the WMR200 over the WMR88 is the external antenna. Oregon Scientific’s wireless weather stations are famously awful at reliably picking up remote sensors. I did not expect a great improvement with the WMR200′s rather tiny antenna but at least it gave me scope to apply simple modifications to improve performance which I could not hope to accomplish with the WMR88′s internal antenna.
So is the WMR200′s external antenna more reliable than the WMR88′s internal antenna? That is difficult to say. What I can say is that it is far from perfect. My first site for the WMR200 was less than 10 meters from all sensors with an internal wall and brick wall inbetween. This location gave intermittent signal issues. A complicating factor was that this location was also my office and contains my laptop and router. I suspect that these may have been responsible for some interference with the signal.
After a few weeks of experimenting I had moved the base station into the upstairs hall which gave it almost line of sight to the sensors via a window. This took the interior wall out the equation and eliminated any interference from electronic devices. The new location experienced less signal drop-outs but did not cure them completely. I then implemented a simple modification by attaching a metal radio aerial to the existing antenna using a bulldog clip:
Since the base station move and my simple modification I have experienced minimal signal drop outs. Specifically, a few weeks apart and lasting no more than 5 minutes. This is more than acceptable for my purposes. Getting the best from the WMR200 appears to be a combination of closest location to sensors, line of sight to sensors or minimal obstacles, minimal electronic interference and putting more metal in the air.
I have attached my data logger via the supplied USB cable to the WMR200 through the wall. The WMR88 has been relocated to the living room downstairs for display purposes. Handily this means that I can now check the current conditions without changing floor.
On the subject of the data logger I have installed a SheevaPlug running Meteohub weather server software. I will detail my experiences with the data logger in an upcoming post. For now it will suffice to say the SheevaPlug/Meteohub combo is a nice piece of kit that is easy to set up and is feature packed.
I am happy with the WMR200 now that I have it working reliably. The antenna issues make it far from plug and play and any prospective buyers should be prepared to put a lot of effort into minimising signal drop outs. In hindsight I would have bought a WMR200 in the first place rather than the more basic WMR88. On the other hand, I find the flexibility of having two base stations to be the perfect setup and an advantage of having a wireless as opposed to a wired weather station.
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