What is UVLO of mains PSU's?

[Flyback]

Hi,

Neither LCS100US15 (100W) or LM25-23B15 (20W) Offline PSU’s tell in their datasheet what is their mains UVLO voltage.

Do you know?

LM25-23B15 (20W)
https://www.mornsun-power.com/html/pdf/LM25-23B15.html

LCS100US15 (100W)
https://www.xppower.com/portals/0/pdfs/SF_LCS100.pdf

We want to put them in an enclosure with an inrush limiter up front…but need to know how low VAC input they operate down to? (if we cant switch the inrush relay on to short out the inrush resistor at low vac input, we're in trouble..the inrush limiter has its own wee mains txfmr based supply)

 

[Pommie]

.the inrush limiter has its own wee mains txfmr based supply

Are you from Scotland?

Mike.

 

[rherber1]

If you want both units to produce maximum output power at the same time using a common inrush limiter it isn't possible. The LC25 has a Vin low voltage of 120V in while the LC100 has 163V. They also have widely varying startup delay. These units are not well matched imo.

Due to the load characteristic versus input voltage for both types you would need to work on a UVLO of Vin = 163V (ie. the minimum Vin for the LC100 for maximum current output)

 

[rherber1]

It might be a better move to use 2 identical 15V, 7A power supplies so that they are matched. The fact that one is lightly loaded is of little consequence.

LM100-20B15_Industrial Switching Power Supply Manufacturer - MORNSUN

You could use a single inrush limiter as per your original idea but it would have to handle the inrush current for both units. Each psu has an inrush current of around 65A at 230Vac - so, 130A total.