Service manual

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• Keep the work area free of non-conductive objects such as Styrofoam-type cups, polystyrene foam polyethylene bags,
and plastic wrappers. Non-conductive devices that are necessary in the area can be kept from building up a static charge
by spraying them with an anti-static chemical such as part number 92176S.
• Do not wear nylon clothing. Keep clothing of any kind from coming within 12 inches (0,3 m) of static-sensitive
devices.
• Do not allow long hair to come in contact with static-sensitive assemblies.
• Do not exceed the maximum rated voltages specified for the device.
Overall Troubleshooting Procedures
To avoid the possibility of personal injury remove the instrument from operation before attempting any
service procedures. Turn off ac power and disconnect all wires from the mainframe and modules including
input leads sense leads GPIB cable and the ac line cord. Make connections to the instrument only as
required for a specific procedure.
AC mains voltage is present on exposed pins on the top edge of the mainframe GPIB Board and each
module whenever the unit is turned on.
Overall troubleshooting procedures for the Electronic Load are given in the flowchart of Figure 3-1. The procedures first
ensure that an ac input failure or bias supply failure are not causing the problem and that the load passes the turn-on selftest
(no error messages). The normal turn-on selftest indications are described in Chapter 3 of the Operating Manual.
If the load passes selftest, Figure 3-1 directs you to perform the front panel verification procedures to determine if any load
function(s) are not calibrated or are not operating properly. If the load passes the front panel verification tests, Figure 3-1
checks to see if the load can be programmed from an GPIB controller. If the load fails any of the tests, you are directed to
the applicable troubleshooting procedure. Signature analysis (SA) is used to troubleshoot the load's primary and secondary
microprocessor circuits. The SA mode is also used to generate waveforms which are used to troubleshoot the analog
circuits. In addition, a list of test points with signal measurement information is provided to help you troubleshoot.
Selftest Sequence and Error Messages
The turn-on selftest sequence consists of tests on both the primary and secondary circuits. The word ' 'primary' ' refers to
either the primary interface or primary processor. Any Agilent 6050A/6051A mainframe failure is a primary failure and
troubleshooting procedures should begin with the GPIB board. The words ''secondary" or "channel" refers to the secondary
processor and analog circuits found in the modules. For all secondary or channel failures, troubleshooting procedures should
begin with the module. All hardware errors are secondary errors.
Note: The initial failure symptom is based on visual observation. At power-on, LOOK at the Agilent
6050A/6051A front panel LCD for an error number or message. Since it is possible to miss seeing an
error at power up, simply repeat the test by turning power off then on again.
If the load fails the selftest, the input will remain disabled and the display should indicate the type of failure. Table 3-2 lists
all of the selftest error codes that can appear on the front panel display and provides the appropriate troubleshooting
information.