Non EV LED Lighting PSU Question

[NeilP]

If my mate that painted it had been happy with the original built in light system on the lathe, I'd not be doing this

We bought it together 3 years ago.

Saddle gearbox was shagged...so we stripped it and rebuilt it...But Dave, wanted to make it look shiny too...so he started stripping irreklant bit to paint it up..f..ing pointless to my mind but he wanted to do it..so we never got around to finishing it..it has been sitting under a cover for three years.

Then the other day we got keen again...and he now decides that he did not like the basie original 50 VAC built in incandescent lighting unit..ok so it is a bit naff and yellow light but at least it worked.

So i thought ..lets just replace the 415 volt t-50 VAC transformer with one that puts out 240 instead..then run everything off it...

Have been looking on RS components I might now get a 420 to 2300 volt transformer.

gives options on the input side to 'tune ' the output voltage

got this from the maker of the DRO

Thank you for your email. The specification for the Topaz operating voltage is 115 V AC or 230 V AC, + / - 15 %. This would make the maximum recommended input voltage 264.5 V AC. Your transformer output of 267 V AC is technically outside of the range of the specification. We would not envisage problems using your supply but we cannot he held liable for any damage or injury that may result from connecting to and using the Topaz from the machine supply.

 

[Punx0r]

Replacing the transformer sounds like a tody solution and one from RS (or similar reputable supplier) will at least be safer and more reliable than a random switchmode PSU from China. 230V is one thing but 415V makes me twitchy.

Regarding the input voltage to the DRO you could initially attach a ballast resistor in parallel with the DRO, as suggested above to stabilise the transformers output around 230V then repeat with successively higher values of resistor until it's effectively just the DRO loading the transformer. If the voltage is still sensible you know the load of the DRO alone is sufficient to stabilise the transformer's voltage to nominal. It's more faff but removes the uncertainty of just connecting up the DRO potentially letting the smoke out when powered up for the first time. 99% chance it'll be fine, but that 1% could be expensive so I get where you're coming from...

 

[NeilP]

I've been looking through RS. Some little ones there , 440-430-420-410-400 type input tappings with labelled 230 out.

as opposed to the one I bought from ETE, single in single out 415 in 240 out.

With the RS one gives the chance to connect to higher input windings so lowering the output voltage.

Rather go that way than run the risk of the resistor eventually diving and the full 267 ming back up the DRO.

Playing SDR radio this morning with a Raspberry Pi SDRPlay RSP1a and also a USB TV Tuner dongle ...\
strangely the USB stick is outperforming the expensive RSP1a by long streak. with the same antenna. Which is very odd, the SDR Play device is just so deaf...which is plain wrong..so has to be a config setting some where for gain or the like....