multiple voltage regulators on same hatsink ?????

[mark krawczuk]

hi, i`m making up a power supply , with four 78 XX series regulators
and lm317 adjustable reg.

is it ok to bolt all these on the same heatsink without insulating
washers ?

thanks,
mark k

 

[Lostgallifreyan]

"mark krawczuk" <krawczuk@adam.com.au> wrote in news:-5CdnXf6U-
5uh5bUnZ2dnUVZ_gmdnZ2d@adnap.net.au:

hi, i`m making up a power supply , with four 78 XX series regulators
and lm317 adjustable reg.

is it ok to bolt all these on the same heatsink without insulating
washers ?

It's probably ok with the 78xx types, if they all ground to the same place
because GND is on the tab and centre pin. Mount the LM317 on insulators
though. If in ANY doubt about the chassis potential, insulate all devices.

 

[cassiope]

On Oct 31, 7:49 am, "mark krawczuk" <krawc...@adam.com.au> wrote:

hi, i`m making up  a power supply  , with   four   78 XX series regulators
and  lm317 adjustable reg.

is it ok to  bolt  all these on the same heatsink  without insulating
washers ?

thanks,
mark k

NO!

 

[Eeyore]

mark krawczuk wrote:

hi, i`m making up a power supply , with four 78 XX series regulators
and lm317 adjustable reg.

is it ok to bolt all these on the same heatsink without insulating
washers ?

NO.

Graham

 

[Eeyore]

Lostgallifreyan wrote:

It's probably ok with the 78xx types, if they all ground to the same place
because GND is on the tab and centre pin.

Just be careful about where currents flow to and from.

Graham