Troubleshooting AC-Turn-On Circuits

Relay AlK1 closes at 2.5 seconds and AC FAULT goes high at 2.9 seconds after 21V UNREG reaches about 13Vdc.

AC FAULT high enables the PWM if OVERVOLTAGE , INHIBIT , and OVERTEMP are also high.

Circuits Included. High AC and AC Dropout Detectors, Bias Voltage Detector, Q11A, 3-Second Delay and Relay Driver-- all on A2 control board.

Setup. The Main Troubleshooting Setup, Page 53. Apply the ac mains voltage to the isolation transformer, and set the external supply to 0Vdc.

Inputs:

 

 

 

NODE (+) *

SETUP

MEASUREMENT

SOURCE

A2J7-24

 

5.0Vdc

A209 (emit.)

A2J7-22

 

≈ 21Vdc

A1CR2,A1CR5

A2Q11-16

 

f.w.rect,0.8V pk

A1CR3,A1CR4

A2U20-13

 

TTL sq wave,20KHz

A2U20-6

Outputs:

 

 

 

NODE (+) *

SETUP

MEASUREMENT

 

A2U17-9

cycle power

≈ 13.5Vdc

 

A2U17-14

cycle power

≈ 1.4Vdc

 

A2Q11-14

cycle power

transition 0 to 5Vdc at 25 sec

 

A2Q11-4

 

Hi (5Vdc)

 

A2U9-10

cycle power

2.9 s burst 1.25KHz sq. wave

 

A2U9-15

cycle power

one 840ms pulse then Hi at 2.5 sec

 

A2U9-14

cycle power

three 420 ms pulses then Hi at 2.9 sec

A2U9-1

cycle power

transition Lo to Hi at 1.7 s

 

A2U15-10

cycle power

transition Lo to Hi at 2.9 s

 

(

 

)

 

 

 

AC FAULT

 

 

 

A2Q7-C

cycle power

transition 5.0 to 0.3Vdc at 2.5 sec

 

RELAY ENABLE

*Node( - ) = A2J7-4

Troubleshooting DC-To-DC Converter

Parallel NOR gates A4U1, A4U2 and A4U3A act as drivers and switch on FETs A4Q1,Q2,Q3 and Q4 through pulse transformer A4T1. NOR gate A4U3B turns off the FETs through pulse transformer A4T2 and transistors A4Q5 and A4Q6.

Circuits Included. On-Pulse Driver, Off-Pulse Driver, FET Switches and Drivers on A4 FET board.

Setup. The Main Troubleshooting Setup, Paragraph 3-40. Apply the ac mains voltage to the isolation transformer, set the external supply to 40Vdc, and switch on the LINE switch. Set the unit's output voltage to 20Vdc and current to above 1Adc. Using the DISPLAY SETTINGS switch. Verify that the OVERRANGE LED lights. See Figure 3-7 for waveforms.

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Agilent Technologies 6030A, 6035A Troubleshooting AC-Turn-On Circuits, Troubleshooting DC-To-DC Converter, Inputs Node +