Adding an external sensor to the WS1

We wanted to measure the soil temperature in the greenhouse, so we ordered an external sensor for the Ubibot WS1 that we have just bought. It wasn’t expensive – £16 from Amazon. We thought that soil temperature might be just as important to the plants in the green as the air temperature.

The sensor arrived next day and it simply plugs into the micro USB port on the side of the WS1. What did surprise me, however, was that the WS1 measures the temperature of the external probe AS WELL AS the temperature from the WS1 itself. In other words, it is measuring two different temperatures. This obvious as soon as you look at the Ubibot dashboard.

WS1 external temperature probe
External probe available for the WS1 on Amazon

This makes the WS1 and an external probe a really cost effective solution. If you didn’t want to measure soil temperature, you could measure the temperature outside the greenhouse as well as inside the greenhouse. This was something that I was already considering. And all from one sensor!

Ubibot dashboard
Temperatures from the WS1 itself (top left) and from the attached external probe (bottom right)

New Greenhouse

We installed a new Robinson’s greenhouse a few weeks ago. It is a 14ft x 8ft Robinson Rushmoor greenhouse. This one is aluminimum and powder coated to a pastel green (I think they call it “sage”!). It matches the window frames on the house. It was ordered last November and it arrived at the end of February.

Working out where to site the greenhouse was reasonably straightforward since we didn’t have many options. And none of them were particularly flat. We had to take down an old dry stone wall (to the right in the picture below) and the new greenhouse will now form part of the field boundary. To get things relatively level, we dug some foundations and then brought up some blockwork on the one sided (to the left in the picture below). Then the small dwarf wall was built on top of the blockwork.

The dwarf wall could have been single or double skin (i.e. one or two rows of bricks). We opted for a double width wall. Having seen the price of bricks, I wish we had opted for the single skinned version! All the groundwork took is 3 weeks to complete. Just in time for the fitter to work his magic on the greenhouse. It took a professional fitter 2.5 full days to install this greenhouse – I hate to think how long it would have taken me to do it!

The end result looks fab!!

Digging the foundations for the greenhouse. The soil from the trenches is piled up in the middle as much as possible.
Concrete laid. All three tonnes of it! We have used blocks to create “steps” in the concrete
Once the blockwork is up, we can sort out the soil in the inside. The dwarf wall is going to sit on top of the blockwork and the blockwork is going to be covered with “feather boarding”.
Outside skin of bricks in place and the returns for the doorway done!
Dwarf wall now complete. Two rows of bricks with a set of “soldiers” on top. These are engineering bricks with no holes or frog is this will allow the greenhouse to be fixed directly to the bricks. 4 tonnes of soil put inside the greenhouse to bring the floor level up to the bottom of the dwarf wall internally.
Frame installed, no glass.
Glass and fancy finials added!

Greenhouse temperature

Having just installed a new greenhouse, we thought it might be a good idea to monitor the temperature in greenhouse. You would think that there are lots of solutions out there. Nothing complicated. Just a display in the house showing the current temperature in the greenhouse, plus maximum and minimum. Maybe a graph. And connected wireless somehow.

There must be loads around. Let’s look on Google! MMMmm. I must be searching on the wrong terms. Where are they?

The closest I could find is a solution from a company called Ubibot. You will find them here: Ubibot.com. They produce a variety of WiFi environmental sensors for industrial and commercial use. I bought one of their cheaper sensors (WS1) for £78 on Amazon just to see if I can get it to work. Ubibot have a store page on Amazon. You will find it here. The WS1 sensor measures temperature, humidity and light levels. More than a enough for a greenhouse!

Image of the Ubibot WS1 sensor.

According to the blurb that comes with the device, 2xAA batteries will power the device for 4-6 months based on readings that are taken every 15 mins. The device connects to the internet via WiFi and the data is stored in Ubibot’s cloud based platform. There is no subscription fee and it is free to use within certain usage limits. It is clearly designed for much larger scale use and I doubt that one sensor in a greenhouse is ever going to reach the limits of the free account.

The Challenge

The main challenge with this device is setting it up. Obviously with a device at this price point, it has a pretty limited user interface and this can be a challenge when setting it up. Combine this with some fairly scant instructions and if it doesn’t all go to plan first time, then you can be in trouble. This happened to me as something went wrong when I was trying to connect it to me home WiFi. I was trying to do this using my iPhone and connecting to the devices on WiFi network. Somehow, it all went wrong. Even though I had followed the instructions. I reverted to the PC based pages. That didn’t help either.

I finally cracked it by using Ubibot’s PC offline tools. You can download them from here. There was the briefest of mentions of it in some of the Ubibot support pages. It allows you to connect to the device using the micro USB port and set it up without connecting to it via WiFi. You have to download some software from the Ubibot site (the install was a little quirky!), but it was a cinch to set up via this route. I wish I had tried this in the first place as it would have saved so much time! It was much easier than trying to connect to it via WiFi.

Once set up, it connected to my home WiFi network and started posting measurements every 15 minutes! The device (and it’s measurements) appear on the Ubibot data warehousing pages. The main screen shows the latest readings and clicking on the device opens up a set of historical graphs. Wow!

The good stuff

  • Even though my iPhone was showing only one bar on my WiFi, the WS1 has connected to our WiFi in the house. I am guessing that it is 20m to the greenhouse through a number of thick masonry walls. The WS1 only supports 2.4G WiFi and not 5G WiFi so it is more susceptible to physical obstructions between the access point and the sensor.
  • Now the data from the WS1 is on the Ubibot platform, I can set up a number of alerts (e.g. sending an email) if some of the data readings reach particular limits. There are some really cool options here. Most of them totally OTT for a greenhouse!
  • Now the data is on the internet, it is possible to view it from anywhere or even share the data with others. Just on the off-chance that someone wants to know the temperature in your greenhouse!
  • It integrates with Alexa too! You need to add Ubibot as a skill to Alexa. Just follow the instructions here then you can say “Alexa, what is the temperature of the Greenhouse?” It took me a couple of minutes to set this up. I wasn’t sure how useful this feature might be – either way, it makes a cool demo!
Summary table from the Ubibot site displaying the WS1 sensor that has just been installed.
Here’s the view from the data warehouse table view.
Detailed information page for this sensor from the Ubibot site.
Here’s the detailed sensor view. There’s not much data here yet as I only got it working this morning!