Best place on hot water cylinder to mount DIY thermostat ?

[picbits]

I think you deliberately misused the word "manufacturing" - I'd call the thing that you can do "fabricating".

And you seem to have ignored my point about the value of your time.
My own time is worth an awful lot more than £0 per hour.

You're a picky bugger

On a serious note though - I didn't realise how cheap the strap on stats were or I wouldn't even have considered building my own.

The value of my time varies quite a lot - I look after a child with a disability while the other half goes out to work. While he is at school and I've got orders or stuff to design then my time is worth a lot. When its quiet and no orders and I'm feeling a bit skint then building stuff like this myself makes economic sense.

 

[Balenza]

Picbits wrote

Aye - a small PIC microcontroller costs me around £1.50

What can it do ?.
Sounds like a right bodge up. A decent engineer would incorporate a small Siemens or Rockwell controller. About £100.

 

[picbits]

Picbits wrote

Aye - a small PIC microcontroller costs me around £1.50

What can it do ?.
Sounds like a right bodge up. A decent engineer would incorporate a small Siemens or Rockwell controller. About £100.

To simplify it - its basically a small computer. They have the same processing power as an old ZX Spectrum or Commodore 64.

You buy them as a blank chip then write code to go into them. There are a variety ranging from one with a couple of inputs and outputs to ones that incorporate USB/Canbus/Serial and many other features.

The ones I use for £1.50 have 18 pins and 16 of these pins can be used as either inputs or outputs. Some pins can read a voltage from 0-5 volts and these are useful for temperature sensors. They can run at up to 10 million commands per second so taking a voltage from a sensor, comparing it to a preset voltage and turning on or off a relay is childs play to them (if programmed correctly).

I have used them to control washing machines, car dashboards, digital speedometers to name a few applications.

You'll find that most of the controllers for boilers and digital temperature controllers have some kind of microprocessor in them.

They are pretty useless on their own though and you need to know how to program them before they become anything useful but I've had 7 years experience programming them and over 20 years in the eletronics industry so I'm getting reasonably good with them now