Wednesday 30 November 2016

Goodbye X10 home automation

The time has come to bid farewell to X10 home automation for me. Slowly over the past year the devices have started to malfunction, switch modules stopped responding, transmitted events from my CM11 computer interface got weaker and weaker and the whole X10 alarm system was just a joke from the start.
So it's now time for me to ditch X10 completely, shutdown my heyu software (on linux) and disconnect the old CM11 unit from the serial port on my server.
It's been used for a long time, in this house and my last house, and to be fair it's done a good job over the years as it was a decent system early on in home automation days (10 yrs ago). It's main issue was the way the modules connected to the mains supply and watched for power-line signals to carry the on/off commands. Often those commands were missed due to other electrical noise on the wire (clothing dryer on, hairdryer, etc), and because most of the modules weren't two-way they couldn't tell the sender that the command had worked or not, so you just had to fire the commands blindly.

Now onto the current system, which I'm afraid isn't currently much better, but it has a bit more potential and more importantly has a cheaper cost. I'm using the 433Mhz unbranded RF system. This is available in most high street shops as 'remote plugs' where you get a little 4-channel remote and 2 or 3 plugs. Plug your appliance into them and use the remote to send an ON or OFF signal to them. Again they're not 2-way so fire and forget, but the cost is dramatically reduced when you can buy the pack for around £15 (A single switch module for X10 used to be more like £25 each).

The 433Mhz is common to Arduino and other development boards, so I've coded up a board with transmitter and receiver to do my tasks for me, and although I do sometimes get missed events, it's proving decent. I've not really done much on distance yet but that will come soon.

So the tasks it has to do for me:

  • Front room uplighter - This is on and off on a timer sequence controlled by my linux server to match dusk time (light level from external sensor) and then turn off at predetermined times
  • External garage lighting - Downlighters to illuminate the exterior of the house and garage, again using dusk time and then daylight.
  • Power to wifi AP - to control when the 'guest' wifi network is available.
  • Misc power - Christmas lights probably going to be the next use for this

Tuesday 22 November 2016

Fixing white goods and the spare parts scam

I'm sure a lot of people have had this problem. Some of their kitchen appliances (white goods) have failed and normally the appliance is quite a few years old. Now I know a lot of people aren't into pulling their electrical items apart, so will inevitably call somebody out who will say one of the following:

  • "Appliance is too old, it needs replacing"
  • "Uneconomical to repair, replace it"
  • "Parts are hard to get for this now"
Or one of another similar list of reasons. Now the problem is this, manufacturers like to keep updating their product line, give you the shiny new colour, new front control panel with more buttons, make it more ECO-friendly, or one of many other things. Most of this is so they can sell more appliances, etc. Which is fine. Except in a lot of these items (Dishwashers, fridges, cooker, washing machine, dryer, microwave, television, DVD, etc) we don't buy regularly, we keep them for a long time and run them until they completely die. They get quite a bit of abuse. Think about your fridge for example. On 24x7, if it misses 5 minutes of being on you'll panic and curse at the device. So that 24x7 is quite punishing on the components, the compressor pump, cooling pipes, electronic (or mechanical) temperature controller, etc. And in the good old days, they were made to last, the components were decent quality, they were manufactured with care and tested well for their runtime expectations.
Now unfortunately I don't believe that's the case with modern devices. I don't believe the components are made to a good standard, they're not tested for longevity and in some cases are assembled and rushed out of the factory so quickly that genuine errors or details are missed that will cause premature (?) failure of the components.

So now onto my way of doing things. I very rarely call in a repairer to look into these things. I'll always take a look myself first. A lot of household appliances are quite simple in how they operate and all work to a few simple principles. Generally, power goes in, gets converted, switched or regulated and will then drive one or more items to produce the end result (Heck, apply that to everything in your life!).
Now onto the parts. Parts ARE available for pretty much everything. And they aren't as specific as the manufacturer or assembler likes to make you think. After all, a pump can be used in many appliances (Washing machine, dryer, dishwasher), so why would one pump not work for all those appliances? Well generally it's because of the fittings the manufacturer (Or assembler, because let's face it, the dishwasher company won't manufacture the pump, they'll buy it in to specification and assemble it into their device) decided to use that makes it 'unique' to their product.

That takes me onto replacement parts. The spare parts industry is huge, and it can be as people need spare parts, either the fitter who comes out and fixes your appliances, or the DIYer who needs the spare part. Either way we know we need xyz part for our shiny appliance, and so we happily tap that appliance and part into the web and duly order the part we're told we need.
I'm guilty of that. I realised this over the past few days, and now I've realised it, I'm banging my head against the desk. Why would it be a specific part for that appliance? Surely if we know the specifications, we can use any old part. OK we might have to adapt it, or use a different fitting, but that ultimately will work! (Caveat, if you don't know what you're doing with electical systems, plumbing, etc, be wary of this approach!)
So just for future, THINK before ordering the part you're told to for a specific appliance, model and part. Look wider and think, can I do this using more basic off the shelf parts? Try local DIY store or plumber/builders merchants, as chances are the pipe, pump, fitting, electrical switch, motor, etc, are easily sourced and will fit with the right tweak or enclosure!

Also, be wary of the online spare parts industry, specifically for your white goods. These guys are also into ripping you off, stating 'alternative' similar parts or similar wording. Most times their part/product listing database is nowhere near accurate. E.g. you tell it you want part xyz for appliance manufactured by abc model def. Their database tells you a similar part you need, but will ALWAYS contain the words "Please check specifications before ordering/fitting" which basically means they're trying to sell you anything they want, regardless of if it'll fit or not! They'll then try to get you to by the "Genuine" manufacturer part at higher cost, but then won't state the dimensions or specifications for this manufacturer part!
Here is a DIRECT quote from such a website, when somebody dares to ask the specifications of a "genuine" manufacturer spare part:

"what is the internal diameter of the rubber end ?" - User question
"Our parts usually do not have measurements listed as they are model specific. As long as your model number matches this part, it will fit your appliance." - website answer