Printronix L1024, Maintenance Manual

Page: 163 / 372

8–31 Chapter 8 – Power Supplies
8.4.2 Reassembly and Replacement
Reverse Steps 1 through 17 listed above.
8.4.3 Adjustment
With rare exceptions, the high voltage power supply should not require adjustment. However, in the event
that adjustment is required in order to return the printer to specification, use the HVPS adjustment
procedure that follows.
WARNING: HIGH VOLTAGES are present in numerous places throughout the
High Voltage, OPC, and Developer assemblies when the printer is
turned on.
The table that follows lists specifications, connections, and control interface for the HVPS. Use these as a
guide to adjusting the small controls on the side of the HVPS itself.
See Figure 8–19.
NOTE: The user-adjustable developer bias knob on the top of the HVPS must be
set to “3” when making the following adjustments.
Table 8–2. High Voltage Power Supply Adjustments
Signal
Engine
Controller
Connector HV Supply
Connector
Channel
HV Output
Connector
Adjust Output Value Definition
+24V J10–1 6 – – – – +24 VDC
supply
Charge J10–2 5 CH1 CN1 VR1 400
±
25mA Charge
corona
Develop J10–3 4 CH4 CN2 VR22* –550
±
50 VDC Developer
bias
Transfer J10–4 3 CH3 CN3 VR31 4.6
±
0.1 kVDC Transfer
corona
– – – CH6 CN6 VR61 –720 VDC
(parasitic
from charge) Charge grid
BGND J10–6 1 – – – – Analog
ground
*With VR21 set to “3”.