[AMPS] resistors

[Rich Measures]

Carl said:
>
>Which is why 100K is the suggested max in any literature I have seen for 
bleeders. 

€  References, please.  .  In a typical 8171 anode-supply, a 100k-ohm 
bleeder would dissipate 810 watts.  

>>>>If I wanted a Reliable bleeder for a 4kV C-filter supply, I would 
>>>>series up 8 to 10  Matsushita/Panasonic 100k-ohm, 3w MOF resistors on a 
piece of 
>>>>perfboard and be done with it.  
>>>
>>>Absolute YUK !  800K to 1M bleders..no way Jose.
>>>
>>Ä  What is to be gained by using a 200k-ohm bleeder on a C-filter, Carl?
>
>Quicker HV bleed down time, less chance of a recharge. 

€  What mechanism recharges the capacitor?  

>  All my concerns are safety related and for others not well versed in PS 
issues.
>
>A string of 3W does not offer much of a voltage breakdown safety margin.
>Matsushita not a common distributor item and similar wattage Panasonic,
>etc are only 350V.  

€  The manufacturer's (Panasonic/Matsushita)  rating at 70 deg. C ambient 
is 500v or 3w .  For a 100k-ohm unit, the realizable dissipation is 2.5w 
at 500v.  .  



Rich...

R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures  


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