Power Supply System Discussion Topics Steve Virostek / John Joseph LBNL Spectrometer Solenoid Workshop May 10, 2011

Spectrometer Solenoid Workshop John JosephPage 2 Outline o System Overview o Status of “pending issues” o Detailed list of 9 items from vendor o What are the new Issues & Concerns?

Spectrometer Solenoid Workshop John JosephPage 3 Simplified System Block Diagram

Spectrometer Solenoid Workshop John JosephPage 4 “Pending Issues” (1) o Personnel Protection System o Power inhibit logic based and does not disconnect AC mains o Power On sequencing can produce high current surge if done incorrectly o Power Supply Ground Reference o DC output of 300A Main PS floating wrt GROUND o Vendor added 10 ohm resistors from V- to earth ground point o DC output of 60A Trimming supplies should be floating, but are connected to earth through 100 ohm resistor

Spectrometer Solenoid Workshop John JosephPage 5 Trimming Power Supply Block Diagram

Spectrometer Solenoid Workshop John JosephPage 6 “Pending Issues” (2) o AC Mains Power Distribution o “The mains wiring has not been specified and must be designed to satisfied the installation requirements” o AMI 420 Programmer o Quench detection circuit function is not fully understood o Feedback loop is stable but slow to respond o Can take up to 1 minute to respond to change o Single Quadrant Power Supply o Main, 300A power supply not bipolar o Series diode circuit implemented to allow voltage reversal for faster discharge

Spectrometer Solenoid Workshop John JosephPage 7 Power Supply System Block Diagram

Spectrometer Solenoid Workshop John JosephPage 8 Series Diode Detail

Spectrometer Solenoid Workshop John JosephPage 9 “Pending Issues” (3) o Voltage Tap Isolation o Instrumentation must be floating o Programmable Logic Controller o Vendor Recommendations pending o Instrumentation Cables o Assembly issues o Vendor recommendations pending

Spectrometer Solenoid Workshop John JosephPage 10 Discussion o Are the pending issues closed? o If not – we need to set a schedule o Are there new issues to discuss? o Topics for the Breakout session tomorrow