Duncan PSU Designer II

[MattM]

In several threads here I've seen a recommendation to use a 4A constant current as a load in PSU Designer II.

However, if I try this, the voltage drops to zero. Obviously I need some help in selecting the parameters in PSU 2.

For the transformer I put in 30V, 10.42A, 4.3% regulation (from the Avel Lingberg specs). This results in 31.29V off-load and 0.123 ohms source impedance.

Am using the BRIDGE25 option for a rectifier.

For the capacitors, you have to specify both a capacitance and a resistance. What do you recommend for the resistance value of a 44,000uF capacitor (two 22,000uF in parallel)? I think this is where the problem is, but I have no clue what values to use.

Any ideas? Thanks!

[aaronpiet]

Hi Matt,

for resistance try 10m ( = 0,01 Ohm), the correct value should be in the specifications of the caps.

Peter

[MattM]

Ah, I found it! 0.021 ohms.

It is listed on the Panasonic datasheet. I didn't make the connection between resistance and "ESR", which is how it's listed in the specs.

ESR = Equivalent Series Resistance

Thanks!