Input:

 

 

NODE ( + )

MEASUREMENT

SOURCE

A2U4 (IN), A2C16 (-)

-24Vdc

A1U1, AlC1 ( + )

Outputs:

 

 

NODE ( + )

N0DE ( - )

MEASUREMENT

A2U4 (ADJ)

A2U4 (OUT)

1.25Vdc

A2VR2 (cath.)

A2VR2 (anode)

11.7Vdc

A2R33, A2R34

A2VR2 (cath.)

2.05Vdc

To check if load on -15V is shorted, remove jumper A2W3.

Refer to Down Programmer, page 39, for the + 8.9V bias supply, and refer to OVP Circuit, page 39, for the +2.5V bias supply.

Power Section Blocks

This section contains the blocks referenced in Tables 3-2 and 3-5.

Troubleshooting AC-Turn-on Circuits

Relay A1K1 closes at 1.0 seconds and DROPOUT goes high at 1.1 seconds after 20V (5V UNREG) reaches about 11Vdc. DROPOUT high enables the PWM if OVERVOLTAGE, and OVERTEMPERATURE are also high.

Circuits Included. AC-Surge-&-Dropout Detector, Bias Voltage Detector, U11A, 1-Second Delay and Relay Driver--all on A2 control board.

Setup. The Main Troubleshooting Setup, page 29. Apply the ac mains voltage to the bias transformer, and set the external supply to 0Vdc.

Inputs:

 

 

 

NODE ( + ) *

SETUP

MEASUREMENT

SOURCE

A2J3-1

wait 2s

5.0Vdc

A2Q3 (emit.)

A2J3-22

 

20Vdc

A1CR6, AlCR7

A2U20-8,10

 

f.w.rect.,1-2Vpk

A1CR8,AlCR9

A2U22-13

 

TTL sq wave, 20KHz

A2U22-6

Outputs:

 

 

 

NODE ( + ) *

SETUP

MEASUREMENT

 

A2U20-5

cycle power

transition 0 to 13.5Vdc

 

A2U20-2

cycle power

transition 0 to 1.4Vdc

 

A2Q6-1

cycle power

transition 0 to 5.0 to 0.3Vdc

 

A2Q6-9

cycle power

transition 0 to 0.3 to 5.0Vdc

 

A2U20-6

wait 2s

< 0.25Vdc

 

A2U20-1,14

wait 2s

hi (5Vdc)

 

A2U11-3

cycle power

transition lo to hi to lo

 

A2U18-10

cycle power

burst 1.25 KHz sq. wave 1.1s

 

35

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Agilent Technologies AGILENT MODELS 6023A and 6028A Power Section Blocks, Troubleshooting AC-Turn-on Circuits