PiE3 magnet power supplies

[Peter Winter <peter.winter@psi.ch>]

Dear Dave and Peter,

since PSI wants to integrate a purchase of new power supplies to the 
budget 2007, we have to specify our needs. Robert and I just went 
through the actual settings and looked at the current currents. Assuming 
a momentum of 30MeV/c momentarily, we recalculated the currents to 50 
MeV/c. The maximum current for this higher momentum is 100A (the two 
bending magnets and QSC01). The other quads need something <70A for 50 
MeV/c.
It seems that there are 30A, 50A, 200A, 250A, and 500A power supplies 
available. In principal, the possibility exists to have two power 
supplies in parallel. Because the 200A PS is expected to be more than 4 
times more expensive than the 50A, the rather more reasonable solution is
- 200A for the ASKs and QSC01
- 100A (if existent) or 2*50A in parallel for each remaining magnet.
This still gives us ~25% spare current above the 50MeV/c. However, for 
the calibration at 70MeV/c we could be just on the edge with some magnets.

All of this is just a request and it's not clear at all when and if the 
PS will be replaced. However, it could well be that the replacement will 
be done in steps. So it might be good to specify a kind of priority 
list. Robert suggested to first exchange the magnets in the area but if 
you have other magnets that you think are more critical please let us know.
Peter

-- 
Dr. Peter Winter
OBEA 10/A
Paul Scherrer Institut
CH-5232 Villigen-PSI
Tel: +41 56 310 4786
Fax: +41 56 310 5353