Wanted timer module - what's it called ?

[Adrian Brentnall]

HI Folks

I know exactly what I want it to do - just don't know what it's called (so having trouble finding it online)

For the new kiln - it'd be interesting to have a simple recorder that displays 'heating hours' per firing cycle (i.e. the actual time that the heating elements have been powered on) - as this would give a measure of the actual electricity costs / usage.

So - I'm imagining a little (Chinese!) pcb with 7-segment led displays, that counts the total number of minutes an input has been 'closed'. Also to have a 'Reset' switch or input...

Anybody seen one of these (I've been scouring eBay..) and can point me in the right direction, please ?

Thanks Adrian

[Tim+]

How about an old fashioned mains mechanical clock?

This one's a bit pricey but I'm sure you could find cheaper ones. ;-)

Tim

[Andrew Mawson]

Like:

or:

or:

or:

ebay abounds with them !

Andrew

[Bob Minchin]

No Cigar I'm afraid Andrew! None of the ones you show (or I've been able to find) have a reset option.

I've been looking for one of these for so long without success that the target project has gone away.

Bob

[ARW]

Would anything from here work?

I have not looked it was just a suggestion.

[spuorgelgoog]

resettable elapsed hour or run time meter

I think this is one such, but it's RS pricing not CE (China Ebay) pricing.

Owain

[Capitol]

Fit a 13A spur socket and plug in a mechanical timer.

[Tim Lamb]

In message , Adrian Brentnall writes

Sideways a bit... you can buy reconditioned single phase meters for 25 notes or so.

[Adrian Brentnall]

Hmmm - different Not quite what I had in mind, though...

[Adrian Brentnall]

Got it in one! - it's the 'reset' facility that seems to be missing.... Having seen all the other clever little Chinese modules available - I'd have thought there'd be one to do this....

[Adrian Brentnall]

Could do - but it's kind of 'clunky'.... Thanks

[Adrian Brentnall]

Thanks Adam - I guess it probably would - though I think it'd involve a few extra button-presses to see the result...

[Adrian Brentnall]

Probably. Can you reset them ? Thanks

[Adrian Brentnall]

That's the kind of functionality.... not so sure about the price though One to consider - now just need to find the same thing from China for

1/10 the price! Thanks

[Tim Lamb]

No. They are usually the multiple dial types. You could keep a record of the reading at the end of each session or weekly etc.

[Dave Liquorice]

Not normally but is it so difficult to subtract the start reading from the end reading? It'll also be measuring the actual energy used rather than some calculated value based on two assumed values (actual mains voltage and power drawn by the elements).

eBay seems to have many meters available for £10 - £20. Even DIN rai l mount meters are about.

[Adrian Brentnall]

OK - yes - simple subtraction is possible Thinking about it overnight, the control relays on the homwbrew kiln controller have spare voltage-free contacts available (closing when the elements are energised) - possibly the quickest way to use these is a simple pic board that sees the closed contacts and increments a timer. I've got a prototyping board kicking about here somewhere...

The background to all of this is that the new kiln has ceramic fibre insulation, while the old one had conventional firebricks. (Small thermal mass to heat up, vs big thermal mass that's slow to cool down)

The same model of controller is used on both kilns - and it seems that the one on the ceramic kiln is cycling more frequently than the one on the brick kiln. At the end of the firing schedule, the controller displays 'elapsed program time' - but not 'actual element firing time' - so I was curious to know the power consumption of the new kiln over the whole cycle.

Doesn't need to be ultra-accurate - and I'd rather not wrestle with that darn 6mm2 cable again to connect anything 'inline'..

Thanks

[Brian Gaff]

I was going to say that. Many of these modules were about a few years ago, but seem not to be now. One was a bit like a tape counter that went one digit every minute and the slowest one was days. It had a reset button. No idea where is was used, but not seen any for sale recently. I often think that technology has replaced things that were simple and useful with stuff that is software controlled and hard to use for anything other than what it was made for.

Brian

[Adrian Brentnall]

I think it's called 'progress' Brian! Certainly makes the business of 'repurposing' bits reclaimed from old electronic kit _much_ harder...

[philipuk]

Why not just buy an electric meter?

Philip