Agilent Technologies 6012B EN - Manual (Page 23)

Installation 23
AC Line Impedance Check
The power supply is designed for proper operation with line impedances typically found in ac power lines. However, if the
supply is connected to an ac power line having a high impedance combined with line voltage near the minimum specified
value, (e.g., 104 Vac for nominal 120 Vac), the unit will go out of regulation if it is asked to provide full rated output power.
Such a situation might occur if the supply is connected to ac power an extended distance from the main ac distribution
terminals and/or if the ac power wires from the main ac distribution terminals are of relatively small gauge.
Measurement of ac line voltage at the supply input terminals typically is not a reliable indication of the actual ac line voltage
because of the peak clipping effect of the power supply and the averaging effect of the voltmeter. Symptoms of excessive
line impedance may include erratic or no output from the supply and/or inability of the supply to provide full output power.
If there is reason to suspect the ac power lines to the supply may have high impedance, perform the following check:
WARNING: This check should be performed only by service-trained personnel who are aware of the hazards
involved (for example, fire and electrical shock). Turn the power supply off before making or
breaking any connections to the power supply. Hazardous voltages are present within the unit even
when the power switch is turned off.
a. Connect a variable load to the supply. Using the OUTPUT ADJUST controls and DISPLAY SETTINGS, set voltage
and current (see Section III for detailed description) to maximum rating.
b. Set the load to the maximum rated output current for the power supply (see Appendix A, Figure A-1). The power
supply output voltage should be greater than:
Model Voltage
Agilent 6010A 65V
Agilent 6011A 8V
Agilent 6612B 22V
Agilent 6015A 220V
Agilent 6023A 6V
Agilent 6028A 20V
c. If the supply voltage is less than specified, perform the power limit calibration given in the Service Manual. If the
power limit is calibrated correctly, but the unit still does not provide the required output, then the power supply is not
receiving adequate ac line input.
Repackaging for Shipment
To insure safe shipment of the instrument, it is recommended that the package designed for the instrument be used. The
original packaging material is reusable. If it is not available, contact your local Agilent Technologies Sales and Support
office to obtain the materials. This office will also furnish the address of the nearest service office to which the instrument
can be shipped. Be sure to attach a tag to the instrument specifying the owner, model number, full serial number, and service
required or a brief description of the trouble.