The beam is usually left powered on, but with the
high
voltage contactor open and the capacitor banks dumped and shorted. This
means
that the following are typically already
on:
- The main power disconnect located to the right of the ladder on
the
cell south wall.
- The DNB main breaker located in the top of DNB rack 1 on the
lower
level. Rack one is the leftmost rack.
- The DNB contactor located next to the main breaker in the top of
DNB rack 1 on the lower
level. It is controlled
by two white buttons that open and close the contactor.
The PC located in the upper level blue controls rack should be powered
up and the
Java interface program should be open. If the main beam power is shut
off
for any reason, the DNB camac crate will lose power. In this
case, the PC Java interface should be re-started by double clicking
on the "traffic light" icon labelled "DNB4PSFC" on the PC desktop.
Startup:
- On the Java screen, turn on the 50 V power by pushing the "50V PS
On"
button. You should see the voltage increase to near 50 volts in the
upper
right "U(50V PS)" voltage readout.
- Go down to the lower level. On Rack two lowest level, push the
large
black button "ON" to close the high voltage contactor and open the
capacitor
bank dump switches.
- On the Java screen, start the charging power supplies by pushing
the
"Cha PS On" button. The voltage readouts, "U(C1)" and "U(C2)" should
start
to increase. If the voltage stays near zero, make sure that in the
lower
right of the screen (the "llocks:" section) the door interlocks are all
closed
(indicator is green). If this is red, there is a door switch that is
not
closed on one of the cabinets. Also make sure that all latched faults
are
reset (push the "reset" button). The 50V supply must be on
(see
step 1) or the interlocks will not clear.
- Check the gas pressures at the gas distribution panel at the rear
of
the beam. The Anode pressure should be set to 1.35 Bar abs. The cathode
pressure
should be set to 0.3 Bar abs.
Shutdown:
- Push the "Cha PS On" button to stop charging the capacitor
banks.
- Push the "50V PS On" button to turn off the 50 volt power supply.
- Go down to the lower level. On Rack two, lowest level, push the
large
red button "OFF" to dump and short the capacitor banks.