PSU : prices and differences

[Jonathan]

Gytis,

If your unsure then has a guide just check the voltage coming into building, if it's on the high side then go for the lower transformer to be on safe side.

Measuring it at a random time is pretty meaningless - at any one point on the grid the mains voltage can and does vary by several volts over time. I'd advise getting a transformer based on the standard mains voltage tolerance (i.e. 230+10%=253V in the UK), otherwise the power supply can't be described as stable and safe for the drivers.

So with a 230V to 33V transformer, using the 10% tolerance and 1.1V drop for rectifier, you can expect up to 33*1.1*1.414-1.1=50.2V. Granted that's not likely to occur at all often, but it is over the rated voltage of the drivers so using the 30V transformer is would be less of a risk. If using a 35V transformer (i.e. the spare one I had) then I'd add in some extra diodes or a linear regulator circuit to keep the voltage within the specification.

[JAZZCNC]

Measuring it at a random time is pretty meaningless - at any one point on the grid the mains voltage can and does vary by several volts over time. I'd advise getting a transformer based on the standard mains voltage tolerance (i.e. 230+10%=253V in the UK), otherwise the power supply can't be described as stable and safe for the drivers.

Yes I agree Erring on safe side is best but it will give him a clue to what the supply is doing which he doesn't have NOW. Esp if he checks over a time period.!

I think the 33vac will be fine because the G540 Gecko can handle more than 50Vdc for short bursts and it's very unlikely you'll ever get near that voltage.

[Gytis]

one minute ago I checked the voltage in the house, it was 236-238V

[Jonathan]

Fun fact - if you have solar panels on the roof the mains voltage in your house will rise a little on a sunny day. I've noticed this effect after putting 1.14kWp of panels on the shed adjacent to my workshop...

[JAZZCNC]

Fun fact - if you have solar panels on the roof the mains voltage in your house will rise a little on a sunny day. I've noticed this effect after putting 1.14kWp of panels on the shed adjacent to my workshop...

Another Fun fact- If you live next to Electric sub station Like me then you get free Elecy. . .

[Gytis]

Fun fact - if you have solar panels on the roof the mains voltage in your house will rise a little on a sunny day. I've noticed this effect after putting 1.14kWp of panels on the shed adjacent to my workshop...

Came on Jonathan,
for me enough that I know what is the AC and DC
and now you pushing me to learn what is the "kWp", let me first finish the PSU
btw. it's not my house