Specifications

<Theory of Scorotron System with Two Wires>
Constant-Voltage
Circuit
PC Drum
HV1
HV1 turns ON and DC negative corona
emissions begin from the two corona
wires. A grid voltage according to the
Grid Control pulse is applied to the two
grid meshes.
Since there is a potential difference
between the grid mesh and PC Drum at
this time, the negative charge of the
corona emission flows through the grid
mesh to the surface of the PC Drum,
resulting in the surface being charged to
a relatively even level by the 1st
Scorotron Unit.
During this time, the PC Drum is being
charged and its surface potential
remains low.
Like the 1st Scorotron Unit, the 2nd Unit
deposits negative charge on the surface
of the PC Drum. The potential of the PC
Drum then becomes equal to that of the
grid mesh (i.e., it reaches the grid
voltage as set by the Grid Control pulse).
When the PC Drum potential equals the
grid mesh potential, the DC negative
corona current flows through the grid
mesh though HV1 to the ground. The
surface of the PC Drum will therefore
never be charged above the given level.
Constant-Voltage
Circuit
PC Drum
HV1
M-29