14
Table 2-2. Guide to Recalibration After Repair (continued)
Printed Circuit
Board
Block Name Ref.
Desig.
Perform These Procedures
A8 GPIB Board Voltage DAC All Remote Readback Zero Calibration
Constant Voltage Full Scale Calibration
Voltage Monitor and Remote Readback Full
Scale Calibration
Constant Voltage Zero Calibration
A8 GPIB Board Current DAC All Constant Current Zero Calibration
Constant Current Full Scale Calibration
A8 GPIB Board U5 Remote Readback Zero Calibration
Constant Voltage Full Scale Calibration
Voltage Monitor and Remote Readback Full
Scale Calibration
Constant Voltage Zero Calibration
Constant Current Full Scale Calibration
Initial Setup
a. Unplug the line cable.
b. Remove the top cover by removing the two top-rear screws. Slide the cover to the rear, and pull up.
c. Plug a control board test connector onto the A2J7 card edge fingers.
d. Turn OVERVOLTAGE ADJUST control A3R72 fully clockwise.
e. Disconnect all loads from output terminals.
f. Connect power supply for local sensing, and ensure that MODE switches are set as shown below.
g. Connect a GPIB controller to the power supply.
h. Reconnect line cable and turn on ac power.
i. Allow unit to warm up for 30 minutes with the internal cover on. The cover should remain in place during all
calibrations.
j. When attaching the DVM, the minus lead of the DVM should be connected to the first node listed, and the plus lead
should be connected to the second node listed.
k. At the beginning of each calibration procedure, the power supply should be in its power-on state (turn ac power off and
back on), with no external circuitry connected except as instructed.
l. The POWER LIMIT adjustment (A2R25) must be adjusted at least coarsely before many of the calibration procedures
can be performed. If you have no reason to suspect that the Power Limit circuit is out of adjustment, do not change its
setting. Otherwise, center A2R25 before you begin to calibrate the power supply.
m. Turn off ac power when making or removing connections to the power supply.