- #1
totota
- 6
- 0
Hi.
I have to test a couple PSUs (ripple, regulation, etc.) that are rated 12 V 62.5 A. In order to do so, I need a test load; I was thinking about using nine 2 ohm 100 W 5% resistors (about 3 usd) in parallel (giving 0.22 ohm 900 w). Taking into account the tolerance of the resistors, I get a total current in between 51.43 A and 56.84 A and, for a single resistor, a maximum dissipated power of 76 W.
For the resistors to be able to dissipate their rated power, they need to be mounted on a heatsink (12" x 12" x 0.125" aluminum sheet it's recommended in the attached datasheet). I would like to use a different type of heatsink (specifically, the ones used on computer's CPUs), but I don't know how to tell if that replacement it's valid.
To summarize, my questions will be:
1.- Is this the best way to test the PSUs?
2.- Is my reasoning right?
3.- How do I determine a different heatsink (the datasheet does not give a thermal resistance)?
Thanks in advance.
I have to test a couple PSUs (ripple, regulation, etc.) that are rated 12 V 62.5 A. In order to do so, I need a test load; I was thinking about using nine 2 ohm 100 W 5% resistors (about 3 usd) in parallel (giving 0.22 ohm 900 w). Taking into account the tolerance of the resistors, I get a total current in between 51.43 A and 56.84 A and, for a single resistor, a maximum dissipated power of 76 W.
For the resistors to be able to dissipate their rated power, they need to be mounted on a heatsink (12" x 12" x 0.125" aluminum sheet it's recommended in the attached datasheet). I would like to use a different type of heatsink (specifically, the ones used on computer's CPUs), but I don't know how to tell if that replacement it's valid.
To summarize, my questions will be:
1.- Is this the best way to test the PSUs?
2.- Is my reasoning right?
3.- How do I determine a different heatsink (the datasheet does not give a thermal resistance)?
Thanks in advance.