Meanwell RPS or EPP Series SMPS Voltage Hack?

[AJ3G]

All:

Before I start tearing these apart, I thought someone might have done this modification or hack to the RPS or EPP Series Meanwell supplies. I am trying to determine which resistor provides the shunt regulator feedback. I am trying to increase a RPS-500-18 or EPP-500-18 output voltage to 22 - 23VDC. I have looked at the output section of the supply and the capacitors look more than able to handle this small increase in voltage. 

Normally I would have no problem just going in and tracing this out, but this supply is compact, and looks to be spring loaded (figuratively speaking). I would prefer not to take of the shields and heat sinks to probe around if I can avoid it.

Thanks!

Rich

[TimNJ]

They are LLC resonant designs. You are asking to operate with 'step-up gain', which means it will probably be operating below the resonant frequency. May or may not be a problem, but it's a little different than modifying the output voltage on duty-cycle/PWM controlled topologies. Plus, you don't know how close they are running the synchronous MOSFETs to their max ratings, so on and so forth. I guess you accept these risks.

Anyway, I think there a potentiometer fitted on all of these by default, right?

Check the RPS-500/EPS-500 spec. For 18V, the adjustment range is just 17.1~18.9V (and maybe for reasons like the above). For 24V, the adjustment range is 22.8~25.2V. Sounds like you should start with the 24V as a base instead.

[ajb]

As TimNJ notes most of these have adjustment pots and will often reach outside of the specified range IME. If you need more adjustment range, there are some models that allow the output voltage to be externally controlled over a larger range.  IIRC the RSP-1000 and SPV-300 both have that feature.

[AJ3G]

All:

Thanks for the response. I suppose I could start at 24V. I had hoped I could simply modify the the 18V variant and then return to 18V when I need it.

Rich

[ssashton]

Digging up an old trad - I am looking at using these supplies. What is the difference between RPS and EPP?

Thanks!

[tooki]

Digging up an old trad - I am looking at using these supplies. What is the difference between RPS and EPP?

Thanks!

RPS is medical safety rated. EPP is standard industrial.