Rasurbo RBP-450CL power supply's erratic behaviour

[mariushm]

Re: Rasurbo RBP-450CL power supply's erratic behaviour

I've seen lots of people bitch about the 4 diode desigen. Could someone please tell what is wrong with the 4 diode design ??????
As far as i know it does the same as a rectifier.

In theory, when they're in the bridge rectifier package, the surface area of the whole package acts as a heatsink, so they don't heat as much.
Maybe there's also something about not causing shorts between the leads but I doubt it.

For example, here's standalone diode and a rectifier :

1N5406 (600v 3a) : https://cdn.badcaps-static.com/pdfs/...bfe1b673eb.pdf
GBU4J (600v 4a) :

1n5406:
PD Power Dissipation 6.25 W
R. JA Thermal Resistance, Junction to Ambient 20 °C/W

gbu4j:

PD Power Dissipation 8 W
RθJA Thermal Resistance, Junction to Ambient, * per leg 19 °C/W

the bridge package heats less and can withstand more current

Also, check the derating curves:



If the fan dies and a user has a high load, the standalone diodes may melt or short closed, causing further damages. With the bridge rectifier, even a small plate of aluminum or copper is enough to act as heatsink.

[PeteS in CA]

Re: Rasurbo RBP-450CL power supply's erratic behaviour

The GBU4 is a lower dissipation part and can be mounted on a heatsink to improve its thermal performance. The 1N5406 has no way of heatsink mounting other than its leads, which gets kludgy.

[b700029]

Re: Rasurbo RBP-450CL power supply's erratic behaviour

I like the metallic purple "P4-450W" power supply they have in their picture with other power supply models.

"it's not a wattage rating, it's just the model number for the different colors!"

[Rob Northen]

Re: Rasurbo RBP-450CL power supply's erratic behaviour

In theory, when they're in the bridge rectifier package, the surface area of the whole package acts as a heatsink, so they don't heat as much.
Maybe there's also something about not causing shorts between the leads but I doubt it.

For example, here's standalone diode and a rectifier :

1N5406 (600v 3a) : https://cdn.badcaps-static.com/pdfs/...bfe1b673eb.pdf
GBU4J (600v 4a) :

1n5406:
PD Power Dissipation 6.25 W
R. JA Thermal Resistance, Junction to Ambient 20 °C/W

gbu4j:

PD Power Dissipation 8 W
RθJA Thermal Resistance, Junction to Ambient, * per leg 19 °C/W

the bridge package heats less and can withstand more current

Also, check the derating curves:



If the fan dies and a user has a high load, the standalone diodes may melt or short closed, causing further damages. With the bridge rectifier, even a small plate of aluminum or copper is enough to act as heatsink.

Thanks for the info mate!