Testing a full-Bridge Rectifiers diode Component
 

G'day..
I Need to know how to test this 4 legged single piece component what a
belive is a (Rectifier diode) gotten out of a computer power supply,
which now i suspect of being bad. No is KBL406G, and it has a + and -
marked on the first and last leg 4 all together.

The diode looks simmilar to the following..
http://www.radioshack.com/images/Pro...6/276-1146.jpg

Does anyone have a good diagram with discription on testing these
component.

Thanks.

G'day..
I Need to know how to test this 4 legged single piece component what a
belive is a (Rectifier diode) gotten out of a computer power supply,
which now i suspect of being bad. No is KBL406G, and it has a + and -
marked on the first and last leg 4 all together.

The diode looks simmilar to the following..

http://www.radioshack.com/images/Pro...6/276-1146.jpg

Does anyone have a good diagram with discription on testing these
component.

Thanks.


What was the problem with the PSU?
Did the mains fuse blow violently at switch-on?

Check each leg of the bridge to the other 3 legs with an ohm-meter and see
if any of the diodes are short-circuit.



--
Graham.



%Profound_observation%

DMM, From the AC inputs, the two that may not have any marking. Black lead
to + terminal. DMM in diode check mode. Should show conductance front all
the other leads to the Black Test lead attached to the + Terminal. Inverse,
connect the Red Test lead to the - Terminal, again they should show
conductance from all the leads to the Red Test lead connected to the -
terminal. Reversing the Test Leads, I.E. Red to + or Black to - should show
infinite resistance, no conductance. Just 4 diodes and you are checking the
front to back resistance/conductance.
wrote in message
oups.com...
G'day..
I Need to know how to test this 4 legged single piece component what a
belive is a (Rectifier diode) gotten out of a computer power supply,
which now i suspect of being bad. No is KBL406G, and it has a + and -
marked on the first and last leg 4 all together.

The diode looks simmilar to the following..
http://www.radioshack.com/images/Pro...6/276-1146.jpg

Does anyone have a good diagram with discription on testing these
component.

Thanks.

wrote in message
oups.com...
G'day..
I Need to know how to test this 4 legged single piece component what a
belive is a (Rectifier diode) gotten out of a computer power supply,
which now i suspect of being bad. No is KBL406G, and it has a + and -
marked on the first and last leg 4 all together.

The diode looks simmilar to the following..

http://www.radioshack.com/images/Pro...6/276-1146.jpg

Does anyone have a good diagram with discription on testing these
component.

Thanks.


I use the diode check function on my multimeter, a bridge rectifier is just
four diodes connected around.

Yes that is exactly what has happened the fuse blew first. I change
the fuse with another one of the same rating turned on the unit and the
fuse blew again.
For the Second time with two fuses blown i changed it for the last time
and decided to turn the unit power on again only this time the fuse
remained intact, to my suprise. In testing the power unit Further i
found that a near by 1w 1.6 ohm resistor blew silently, this is located
not far from the fuse itself. Each time i replace this resistor with
the same one it just gets knocked out each time before the fuse does. I
hope that explains a bit of what went wrong.