My New Early Model PL400 w/ 4 Fin Heat Sink

In the standard cap configuration you have a plus and a minus grounded to the chassis....
 
Like Lee said. I went part for part and checked it twice and ordered all nichion muse caps for the main board. Perhaps I did not need muse caps in every position but why not if they are easy enough to find. When I first put my MFC's in I checked that continuity thing with my meter and was baffled as to why I read a dead short from the caps to the chassis. I knew after checking, re checking, photographs, documentation and thru the guys here that it was right so I just went on with the show. I did not want to ask why and how this was and be embarrassed any more than I already was. I thought I knew a little bit about electronics and now I have found that I know less than I thought .
 
Punch. You cannot have the negative terminal of each cap grounded. One minus and one plus is supposed tobegrounded as the caps are seriesed notparalleled
 
laatsch55 said:
Punch. You cannot have the negative terminal of each cap grounded. One minus and one plus is supposed tobegrounded as the caps are seriesed notparalleled
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After looking at the schematic I realized I couldn't use the stud mount caps. If I would have used them the negative rail cap would have been shorted. Not good... I've requested a RMA from Mouser hopefully they allow me to return them. I've identified a 16KuF 100V Kemet that I'll be ordering.
 
In the original configuration, the negative rail cap is also to ground, through the positive post. And the positive rail cap is also to ground through the negative terminal...
 
punchback said:
Since I'm going to be placing another Mouser order I figured I'd get replacements for the few electrolytics that are on the, I guess, PL400C board. Based on the actual board each channel has (1) 10 uF/50V, (2) 40uF/15V, and (1) 100uF/10V. I already have a replacement for the 100uF/10V as specified by laatsch55 (470uF/50V).
Alan
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You cannot buy a 40uF cap in the Nichicon UFG or UKZ series. Given the choice of 33uF or 47uF, which would be most appropriate?

Alan
 
punchback said:
After looking at the schematic I realized I couldn't use the stud mount caps. If I would have used them the negative rail cap would have been shorted. Not good... I've requested a RMA from Mouser hopefully they allow me to return them. I've identified a 16KuF 100V Kemet that I'll be ordering.
Click to expand...

Be warned these Kemets are 2" diameter and will likely run into physical interference inside your amp.
 
The caps that are currently installed are 2"D x 4.2"L Sprague 5900uF 75V. They are up tight against the fuse holders. Other than that there's no clearance issues.
 
Did that myself a few times . Put some 22k/ 100 volters in a 400..
 
I love Mouser's search function. I ended up with the Kemets by searching for a ~2"D x 4"L 100V screw terminal cap. Earlier I was focusing on a 15KuF along with the other details. I've found that you just put a minimal amount of search details and sneak up on the result.
 
WOPL Sniffer... Thank you for the support ;). I know how you feel about putting money into the 400. Everything was going OK until that damn stud mount oversight.
 
These guys here have upgraded a thousand 400's here in these pages. Did you not see what they used for caps?
 
This amp currently has 2"D by 4"L caps installed, as stated before. I really didn't go looking for a cap to use. Based on the date code of 7152 Im sure that's the the cap that's in there from the factory. Why not do what the factory did? I did see the white oak audio solution but I'm not a fan of that look.

I did see that going to a 15K uF or so seemed to be what was typically done. So a 15KuF or so cap that was 2" x 4" seemed to make sense. I'll have the Kemets tomorrow so we'll see if there's any space issues.
 
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