Tequipment Agilent E361 Serie Manual De Funcionamiento Y Servicio página 28

STEP ACTION
1 Short U19 pin 4 to TP6.
2 Measure the voltage from
TP6(common) to TP9.
3 Measure the voltage from
TP6(common) to TP8.
Table A-7. Overvoltage Protection Circuit Troubleshooting
a. Shutdown release
(OVP indicator OFF)
b. Output voltage remains
shutdown(0 V)
a. High voltage (+5 V)
b. Low voltage (0 V)
a. Below +2.6 V
b. Above +2.6 V
RESPONSE
A-12
PROBABLE CAUSE
a. U20 defective or C57
shorted.
b. Proceed to step 2.
a. U19 defective or proceed step 3.
b. U4D defective.
a. U12 or U8 defective
b. U18 defective