Agilent Technologies AGILENT MODELS 6023A and 6028A service manual Bias Supplies, Maintenance

If it is necessary to have all the supplies come up simultaneously after a system shutdown, follow this procedure:

a.First bring the REMOTE INHIBIT line low.

b.Provide a negative-going pulse to the REMOTE RESET .

c.After at least one second, return REMOTE INHIBIT to a high level.

Figure A-10. System Shutdown Using Bias Supply Output

Figure A-10 shows a second method of system shutdown. This method is appropriate in systems which are not controller-operated and in which more than four supplies must be shutdown simultaneously. Because each supply derives its CONTROL ISOLATOR BIAS from the previous supply's + 5V REG, there is no limit to the number of supplies that can be shutdown. Each supply must be reset individually.

Using either method of system shutdown, PCLR inhibits the OVERVOLTAGE indicator from going low and shutting

down succeeding supplies upon initial sum-on. After the supplies have stabilized, PCLR returns to a high state.

Bias Supplies

The outputs of three current-limited bias supplies are available for user-supplied circuitry. These are + 15V @ 75mA at J3-4, -15V @ 75mA at J3-20, and +5 V @ 100mA at J3-23; all with respect to J3-7, L Common.

It may be desirable to install noise-suppression capacitors on the bias supply outputs near the load circuits. The capacitors should be ceramic or tantalum type, approximately 0.1∝F to 10∝F.

Maintenance

The following paragraphs provide procedures and setups to aid in checking and troubleshooting the 002 Option Board. This information, used in conjunction with the schematic drawing and the Operation section of this Appendix, will help in the isolation and repair of faulty circuits.

When testing the option, use of the test connector on page 83 will allow easier access to the J3 contacts.

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