-
Looking for a smarter way to manage your heating this winter? We’ve been testing the new Aqara Radiator Thermostat W600 to see how quiet, accurate and easy it is to use around the home. Click here read our review.
Drill through beam, pull through conduit, or what?
- Thread starter endecotp
- Start date
Before the IEE Wiring Regulations were also adopted by BSA as BS7671 you might be surprised by the level of training on both the Wiring Regs courses and the I&T courses at some colleges .
I’m talking purely about the likes of C&G 238x and 239x courses or equivalents not the in-house training of apprentices by firms large and small with college day release thrown in.
Things were different back then, both good and not so good, the empathise with some was a nice neat job more so than any testing and inspecting by some during the firms own training procedures.
I’m talking purely about the likes of C&G 238x and 239x courses or equivalents not the in-house training of apprentices by firms large and small with college day release thrown in.
Things were different back then, both good and not so good, the empathise with some was a nice neat job more so than any testing and inspecting by some during the firms own training procedures.
Moving coil meters rather than LCD screens and the wind up “Megger” were more the order of the day just before that time.
Actually I do miss the moving coil meters of the old ins res testers because you’d see that initial kick as the capacitance of the circuit under test charged up and that would give an instant big clue even before the needle settled.
Nowadays the display doesn’t show for a few seconds until a more stable figure is produced, it does stop all the excitement LOL.
Wouldn’t be the same if all of the digits were spinning around like a one armed bandit would it?
Actually I do miss the moving coil meters of the old ins res testers because you’d see that initial kick as the capacitance of the circuit under test charged up and that would give an instant big clue even before the needle settled.
Nowadays the display doesn’t show for a few seconds until a more stable figure is produced, it does stop all the excitement LOL.
Wouldn’t be the same if all of the digits were spinning around like a one armed bandit would it?
Indeed. In fact, far more generally, in many contexts I miss 'analogue display' meters, particularly when they are used to give continuous information,rather than just for 'testing' - it's far easier to glance at the needle of an analogue display and see if the reading is 'about right', rather than having to 'read numbers' and then interpret them. Thankfully, we haven't (yet!) lost analogue displays for things like (most) speedometers or aircraft instruments etc.!
For the above reasons, it rather surprises me that we haven't seen a lot more 'on-screen analogue displays' (which are easy enough to implement). One sees them occasionally, but not often. I suppose that 'bars' are quite common in some situations, but something gthat looks like an analogue meter is pretty rare - here is one of the very few examples I regularly see ...
Kind Regards, John
Yup you can’t beat anologue in some situations. Even a simple bar is an improvement in some too.
Yes, indeed - and I agree that even a bar can be better than a digital display.
Latest update: I have obtained some high-voltage capacitors and added them as shown in @SUNRAY ’s edited circuit.
I didn’t want to do this in the obvious way because I felt it could overload the coil; smoothed rectified 240V AC is about 330V DC, and since much of the coil’s impedance is due to its inductance, the current would increase by even more than that would suggest. So I’ve chosen a smallish capacitor value - 0.47uF for this relay - such that it discharges to about 100V during the “off” half cycle. The result is a waveform with an average DC voltage of 247V. That must still dissipate a bit more heat in the coil than 240V AC would but it does work and doesn’t get noticeably warm.
This works on a breadboard.
The crucial question is presumably whether it still buzzes?
Thinking aloud (and particularly if it still buzzes a bit) .... could you not increase the capacitor value considerably (to get a much smoother waveform) and then put a high-voltage zener in series with the relay coil, to reduce the voltage reaching the coil to whatever you wanted?
Kind Regards, John
I like to see somethings that makes you expect Boris Karloff to walk in and throw a knife switch and the Arcs then flow hither and thither and giant needles on moving coil meters jump about ,
A mock up in a local museum on a recent trip near to Dounreay recently has some old looking elements of such that were slightly reminiscent of those bygone meters and switches and sparks etc .
Eeehh those were the days
Being serious, I think the situation in which analogue displays are much preferable is when the quantity being displayed is constantly changing, often by pretty small amounts (a fairly common situation) - that can be pretty difficult with a digital display.Anyone who has tried to align things will have your opinon John. The experts may have a different opinion and say their Sakocacky 123 MFT is the best product ever but thee and me know the truth
Yes agreed, far easier to interpret than spinning numbers, patterns and speed of change show up nicely.
No buzzing?
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
