Agilent Technologies 6812B Line Fuse, Runtime Error Messages, indicates, may appear at runtime

Turn-On Checkout - 3

Runtime Error Messages

Under unusual operating conditions, the front panel display may show OVLD. This indicates that the output voltage or current is beyond the range of the meter readback circuit. If the front panel display

indicates -- -- -- -- -- --	, a GPIB measurement is in progress. Appendix C lists other error messages that
may appear at runtime.

Line Fuse

If the ac source appears "dead" with a blank display and the fan not running, first check your power source to be certain line voltage is being supplied to the ac source. If the power source is normal, the ac source line fuse may be defective. If the ac source has a defective fuse, replace it only once. If it fails again, investigate the reason for the failure. Proceed as follows:

WARNING: Hazardous voltages can remain active inside the ac source even after it has been turned off. Fuse replacement should be done only by a qualified electronics technician.

The line fuse is located inside the ac source. To change it, refer to Figure 3-2 and proceed as follows:

1.Turn off the front panel power switch and unplug the line cord from the ac source.

2.Remove the ac cover as follows:

a.Remove the four screws securing the carrying straps and dustcover (use a T25 Torx drive).

b.Spread the bottom rear of the cover and pull it back to remove it.

3.Observe the two LEDs on each side of the unit. If either LED is ON, there is still hazardous voltages present inside the ac source. Wait until the LEDs are out before proceeding (it may take several minutes for the LEDs to go out.)

4.Replace the fuse with one of the same type. Do not use a slow-blow type fuse

5.Replace the cover.

6.Connect the line cord to the ac source.

7.Turn on power and verify operation.

SIDE VIEW (W ITH COVER REMOVED)

F US ELED

Figure 3-2. AC Source Fuse Location

35