Service Manual For Agilent Model 6611C, 6612C, 6613C, 6614C System DC Power Supply For instruments with Serial Numbers: Agilent 6611C: US37450101 and up Agilent 6612C: US37460101 and up Agilent 6613C: US37460101 and up Agilent 6614C: US37460101 and up Agilent Part No. 5962-8200 Microfiche No 5962-8201 Printed in U.S.A.
Warranty Information CERTIFICATION Agilent Technologies certifies that this product met its published specifications at time of shipment from the factory. Agilent Technologies further certifies that its calibration measurements are traceable to the United States National Bureau of Standards, to the extent allowed by the Bureau's calibration facility, and to the calibration facilities of other International Standards Organization members.
Safety Summary The following general safety precautions must be observed during all phases of operation of this instrument. Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design, manufacture, and intended use of the instrument. Agilent Technologies assumes no liability for the customer's failure to comply with these requirements. WARNING Servicing instructions are for use by service-trained personnel.
Safety Symbol Definitions Symbol Description Direct current Alternating current Both direct and alternating current Three-phase alternating current Earth (ground) terminal Protective earth (ground) terminal Frame or chassis terminal Terminal is at earth potential (Used for measurement and control circuits designed to be operated with one terminal at earth potential.
Notice The information contained in this document is subject to change without notice. Agilent Technologies makes no warranty of any kind with regard to this material, including but not limited to, the implied warranties of merchantability, and fitness for a particular purpose. Agilent Technologies shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance or use of this material.
Table of Contents Warranty Information Safety Summary Notice Printing History Instrument Identification Table of Contents INTRODUCTION Organization Safety Considerations Related Documents Revisions Manual Revisions Firmware Revisions Electrostatic Discharge VERIFICATION AND PERFORMANCE TESTS Introduction Test Equipment Required Measurement Techniques Setup for Most Tests Electronic Load Current-Monitoring Resistor Operation Verification Tests Performance Tests Programming Constant Voltage (CV) Tests CV Se
CV/CC Status Annunciators Troubleshooting Bias and Reference Supplies J307 Voltage Measurements Manual Fan Speed Control Disabling Protection Features Post-repair Calibration Inhibit Calibration Switch Calibration Password Initialization ROM Upgrade Identifying the Firmware Upgrade Procedure Disassembly Procedures List of Required Tools Cover, Removal and Replacement A2 Interface Board, Removal and Replacement Front Panel Assembly, Removal and Replacement A3 Front Panel Board, Removal and Replacement A1 Mai
1 Introduction Organization This manual contains information for troubleshooting and repairing Agilent Models 6611C, 6612C, 6613C and 6614C System DC Power Supplies. Hereafter all models will be referred to as the dc power supply.
1 - Introduction Revisions Manual Revisions This manual was written for dc power supplies that have the same manufacturing dates (the first four digits) as those listed on the title page and whose unique identification number (the last four digits) are equal to or higher than those listed in the title page.
2 Verification and Performance Tests Introduction This document contains test procedures to verify that the dc power supply is operating normally and is within published specifications. There are three types of tests as follows: Built-in Self Tests These tests, run automatically when the power supply is turned on, check most of the digital circuits and the programming and readback DACs.
2 - Verification and Performance Tests Table 2-1. Test Equipment Required for Verification and Performance Tests Type Specifications Recommended Model Current Monitor Resistor 15 A (0.1 ohm) 0.04% Guildline 9230/15 DC Power Supply Minimum 5 A output current rating Agilent 6632B Digital Voltmeter Resolution: 10 nV @ 1V Readout: 8 1/2 digits Accuracy: 20 ppm Agilent 3458A or equivalent Electronic Load 100V, 5 A minimum, with transient capability Agilent 6060B (60V max.
Verification and Performance Tests - 2 -S - + SENSE +S -S - + +S Remote Remote NOTE: Connector SENSE Local Local is removable + - + - 50VDC MAX TO Set to Remote Remote - - DVM, Scope, or DC RMS voltmeter (for CV tests) DVM or 50VDC MAX TO Set to Load resistor 400 ohm Ampmeter + + B.
2 - Verification and Performance Tests Current-Monitoring Resistor To eliminate output-current measurement error caused by voltage drops in the leads and connections, connect the current monitoring resistor between the -OUT and the load as a four-terminal device. Connect the current-monitoring leads inside the load-lead connections directly at the monitoring points on the resistor element.
Verification and Performance Tests - 2 Constant Voltage (CV) Tests CV Setup If more than one meter or if a meter and an oscilloscope are used, connect each to the terminals by a separate pair of leads to avoid mutual coupling effects. For constant voltage dc tests, connect only to +S and -S, since the unit regulates the output voltage that appears between +S and -S, and not between the (+) and (-) output terminals. Use coaxial cable or shielded two-wire cable to avoid noise pickup on the test leads.
2 - Verification and Performance Tests CV Source Effect This test measures the change in output voltage that results from a change in ac line voltage from the minimum to maximum value within the line voltage specifications. a. Turn off the supply and connect the ac power line through a variable voltage transformer. b. Connect the output as shown in Figure 2-1a with the DVM connected between the +S and the -S terminals. Set the transformer to nominal line voltage. c.
Verification and Performance Tests - 2 Loading Transient tttt t v t v Unloading Transient Figure 2-2. Transient Waveform a. Turn off the supply and connect the output as in Figure 2-1a with the oscilloscope across the +S and -S terminals. b. Turn on the supply and program the output current to the maximum programmable value (Imax) and the voltage to the full-scale value in Table 2-2. c.
2 - Verification and Performance Tests c. Divide the voltage drop (DVM reading) across the current monitoring resistor by its resistance to convert to amps and record this value (Iout). Also, record the current reading on the front panel display. The readings should be within the limits specified in the performance test record card for the appropriate model under Current Programming and Readback @ 0 Amps. d. Program the output current to the full-scale value in Table 2-2. e.
Verification and Performance Tests - 2 CC Load and Line Regulation These tests (CC Load Effect and CC Source Effect given below) are tests of the dc regulation of the power supply's output current. To insure that the values read are not the instantaneous measurement of the ac peaks of the output current ripple, several dc measurements should be made and the average of these readings calculated.
2 - Verification and Performance Tests CC Source Effect This test measures the change in output current that results when the AC line voltage changes from the minimum to the maximum value within the specifications. a. Turn off the supply and connect the ac power line through a variable voltage transformer. b. Connect the output terminals as shown in Figure 2-1a with the DVM connected across the current monitoring resistor. Set the transformer to the nominal line voltage. c.
Verification and Performance Tests - 2 Performance Test Equipment Form Test Facility:_________________________ Report Number ________________________ ____________________________________ Date _________________________________ ____________________________________ Customer _____________________________ ____________________________________ Tested By ____________________________ Model ______________________________ Ambient Temperature (C) ________________ Serial No.
2 - Verification and Performance Tests Performance Test Record Form Model Agilent 6611C Test Description Report No _______________ Date __________________ Minimum Specs. Results* Maximum Specs. Measurement Uncertainty − 5 mV __________ + 5 mV 1.6 µV Vout + 2 mV 1.6 µV Constant Voltage Tests Voltage Programming and Readback Low Voltage (0V) Vout Vout − 2 mV __________ High Voltage (Full Scale) Vout 7.991 V __________ 8.009 V 335 µV Front Panel Display Readback Vout − 4.
Verification and Performance Tests - 2 Model 6612C Test Description Report No _______________ Date __________________ Minimum Specs. Results* Maximum Specs. Measurement Uncertainty − 10 mV __________ + 10 mV 1.6 µV Front Panel Display Readback Vout − 3 mV __________ Vout + 3 mV 1.6 µV High Voltage (Full Scale) Vout 19.980 V __________ 20.020 V 335 µV Front Panel Display Readback Vout − 9 mV __________ Vout + 9 mV 335 µV Load Effect Vout − 2.0 mV __________ Vout + 2.
2 - Verification and Performance Tests Model Agilent 6613C Test Description Report No _______________ Date __________________ Minimum Specs. Results* Maximum Specs. Measurement Uncertainty − 20 mV __________ + 20 mV 1.6 µV Front Panel Display Readback Vout − 6 mV __________ Vout + 6 mV 1.6 µV High Voltage (Full Scale) Vout 49.955 V __________ 50.
Verification and Performance Tests - 2 Model Agilent 6614C Test Description Report No _______________ Date __________________ Minimum Specs. Results* Maximum Specs. Measurement Uncertainty − 50 mV __________ + 50 mV 1.6 µV Front Panel Display Readback Vout − 12 mV __________ Vout + 12 mV 1.6 µV High Voltage (Full Scale) Vout 99.900 V __________ 100.
3 Troubleshooting Introduction WARNING: SHOCK HAZARD. Most of the troubleshooting procedures given in this chapter are performed with power applied and protective covers removed. Such maintenance should be performed only by service trained personnel who are aware of the hazards (for example, fire and electrical shock). CAUTION: This instrument uses components which can either be damaged or suffer serious performance degradation as a result of ESD (electrostatic discharge).
3 - Troubleshooting Test Equipment Required Table 3-1 lists the test equipment required to troubleshoot the power supply. Recommended models are listed. Table 3-1.
Troubleshooting - 3 Turn on unit and observe the display. All of the segments and annunciators, the address and then after self test should display an error message or go to the metering mode.
3 - Troubleshooting From Sheet 1 Enable output and program voltage and current full scale with no load. Measure output voltage. Unit OV's? Check to insure OV setting is not less than Yes the voltage setting. If not then replace A1. No Output voltage > 10% error? Yes CV_Prog & CC_Prog OK? (see Table 3-4) Yes Check cable W9, Replace A1 No No Replace A2 Output out of spec but close? Yes Calibrate voltage No Output OK but meter wrong? Yes Calibrate voltage.
Troubleshooting - 3 From Sheet 2 Program current to full scale, voltage to Vmax and load to the power supply's rated current. Supply should be in CC. Will not go into CC or error > 10% ? Yes CC_Prog OK ? (see Table 3-4) Yes Replace A1 No No Replace A2 Output out of spec but close? Yes Calibrate unit No Output OK but meter wrong? Yes Calibrate current. If still wrong or will not calibrate, replace A2 No Turn on OCP and insure Protect trips.
3 - Troubleshooting From Sheet 3 Connect controller to the HPIB port and send commands to set the output voltage and current and readback the output. Accepts and reads back? No Replace A2 Yes Run the Performance Test in Chapter 2. Passes test? No Regulation, Transient Response and ripple problems are generally caused by A1 Yes Short RI terminals on rear of supply and insure output disables and Prot annunciator comes on.
Troubleshooting - 3 Specific Troubleshooting Procedures Power-on Self-test Failures The power-on self-test sequence tests most of the digital and DAC circuits. If the supply fails self-test, the display "ERR" annunciator will come on. You can then query the unit to find out what the error(s) are. When an error is detected, the output is not disabled so you can still attempt to program the supply to help troubleshoot the unit. Table 3-2 lists the self test errors and gives the probable cause for each error.
3 - Troubleshooting E221 Front Panel comm UART framing error A3 Front Panel/Display Bd E222 Front Panel comm UART parity error A3 Front Panel/Display Bd E223 Front Panel firmware input buffer overrun A3 Front Panel/Display Bd CV/CC Status Annunciators Troubleshooting The CV/CC annunciators are particularly helpful when troubleshooting a unit with no output voltage or current. If the unit has passed self test the programming DAC circuits on the A2 circuit board are probably working properly.
Troubleshooting - 3 J307 Voltage Measurements Cable W9 connects J307 of the A1 Main Board Assembly to J207 of the A2 Interface Assembly. Table 3-4 provides a quick method of determining if the voltages between these assemblies are within the normal range. If any of these voltages is outside the normal range, refer to the flowcharts to further troubleshoot the circuit associated with the abnormal voltage. Table 3-4.
3 - Troubleshooting Manual Fan Speed Control Under some circumstances such as testing acoustical devices where the fan noise would interfere with the test, it would be advantageous to reduce the fan speed. If the test requires a very light load, the ambient temperature is low and the duration of the test is short, the fan speed may be temporarily reduced. The turnon default is "Automatic" so this procedure must be performed, as needed, every time the line voltage is turned on.
Troubleshooting - 3 Post-repair Calibration Calibration is required annually and whenever certain components are replaced. If either A1 or A2 are replaced, the supply must be re-calibrated as described in Appendix B of the User's Guide. If the Interface board A2 is replaced, the supply must be initialized first (see "Initialization" later in this chapter) and then be calibrated.
3 - Troubleshooting Initialization The dc power supply's GPIB address and model number as well as other constants which are required to program and calibrate the supply are stored in a EEPROM on the A2 Interface board. The Interface board also contains references and other components that will affect the alignment of the supply. If the Interface board is replaced, the supply must be reinitialized and calibrated. To initialize the power supply: a. Enable the Calibration mode b.
Troubleshooting - 3 Disassembly Procedures The following paragraphs provide instructions on how to disassemble various components of the dc power supply. Once disassembled, the components can be reassembled by performing the disassembly instructions in reverse order. Figure 3-2 shows the location of the major components of the unit. Figure 3-2. Component Location WARNING: SHOCK HAZARD.
3 - Troubleshooting Cover, Removal and Replacement a. Using a T15 Torx screwdriver, unscrew the two captive screws which hold the rear bezel to the dc power supply, and then remove the two screws from the bottom of the case. b. Slide the cover backward until it clears the rear of the power supply. A2 Interface Board, Removal and Replacement To remove the Interface Board, proceed as follows: a. Remove the cover of the power supply as described under, "Cover Removal and Replacement." b.
Troubleshooting - 3 A3 Front Panel Board, Removal and Replacement First remove the front panel assembly as described under, "Front Panel Assembly, Removal and Replacement." Once you have access to the front panel board perform these steps: a. Remove the RPG knob by pulling it away from the front panel. b. Pull back the right side of the board near the RPG about 1/8th of an inch. Slide the board to the left to disengage the holding clips. c.
3 - Troubleshooting Line Voltage Wiring Figure 3-3 illustrates the primary wiring configuration of the power transformer for various ac line voltages. Use long nose pliers to disconnect the wires going to the transformer terminals. NOTE: Install the correct fuse when changing the ac line voltage from a previous setting: for 110/120 Vac: 2.5AT, 250V, Agilent p/n 2110-0633; for 220/230 Vac: 1.
4 Principles of Operation Introduction This section describes the different functional circuits used in the dc power supply. First, the I/O external signals that connect to the Agilent power supply are described. Next, the overall block diagrams for the dc power supply are described in detail. The simplified block diagrams found in Chapter 6 show the major circuits on the dc power supply as well as the signals between circuits.
4 - Principles of Operation A3 Front Panel Circuits As shown in Figure 6-3, the supply's front panel assembly contains a circuit board, a keypad, a display, and a rotary control (RPG) for the output voltage and current. With the exception of the RPG (A3G1), the A3 Front Panel board is an assembly-level replaceable part. A separate front panel binding post board is also included on the unit. It is also available as an assembly-level replaceable part.
Principles of Operation - 4 The EEPROM (electrically erasable programmable read-only memory) chip on the A2 interface board stores a variety of data and configuration information. This information includes calibration constants, GPIB address, present programming language, and model-dependent data, such as the minimum and maximum values of voltage and current. One of the EEPROM storage locations holds a checksum value which is used to verify the integrity of the EEPROM data.
4 - Principles of Operation As shown in Figure 6-2, the ac input rectifier and filter converts ac input to a dc level. The output regulator regulates this dc level at the output of the power supply. The output regulator stage consists of two parallel NPN series regulators mounted on a heatsink and connected between the +Rail and the +Output.
Principles of Operation - 4 When the downprogramming stage is turned on (in either CV or CC mode), the CV/CC control circuit causes the Control signal to go low, which in turn causes the downprogramming transistors to conduct current away from the load and speed up downprogramming. During operation, a PM_Inhibit signal will cause the output stage bias/shutdown circuit to turn off the gated 15 V bias voltages and shut down the output if any of the following occur: The output is programmed off.
5 Replaceable Parts List Introduction This section lists the replaceable parts for all models. Refer to Figures 5-1 and 5-2 for the location of mechanical parts with the reference designators MP.
5 - Replaceable Parts List W-3 W-4 W-5 W-6 W-7 W-8 W-9 W-10 W-11 50 5063-4825 5063-3479 5063-3481 5063-3478 5080-2544 5080-2452 5080-2448 06611-60056 5080-2605 8120-4383 8120-1351 8120-1369 8120-1689 8120-0698 8120-2104 8120-2956 8120-4211 8120-4753 5962-8194 5962-8198 1 1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 Secondary Power Cable (T1 to J306) Secondary Bias Cable (T1 to J305) Output Cable (EB315/ER315 to front panel) Primary Bias Cable (T1 to J303) Display Power/Comm Cable (A2 to A3) Interface Power Cab
Replaceable Parts List - 5 Figure 5-1.
5 - Replaceable Parts List Designator MP1 MP2 MP3 MP4 MP5 MP6 MP7 MP8 MP8 MP8 MP8 MP9 MP10 MP11 MP12 MP13 MP14 MP15 MP16 MP17 MP18 MP19 MP20 MP21 MP22 MP23 MP24 MP25 MP26 MP27 MP28 MP29 MP30 MP31 52 Table 5-2.
6 Diagrams Introduction None Blue -15Vs +15Vs +5Vs R431 Sec Common F309 +Rail Heat Sink Red Brown Opt J320 Grn/Yel Yellow Orange Relay White Gray Violet This chapter contains drawings and diagrams for troubleshooting and maintaining the Agilent Model 6611C, 6612C, 6613C and 6614C System DC Power Supplies. Conductor Side J305 Pri Common F308 D330 D307 F303 F306 +5Vp J304 -Rail F310 F311 J306 J314 J303 F305 J307 +5Vp (unreg) Figure 6-1.
6 - Diagrams Figure 6-2.
Diagrams - 6 Figure 6-3.
T1 56 Figure 6-4.
Index —+— +OUT, 43 +sense, 43 —A— A1 block diagram, 54 A1 board removal, 41 A1 Main board, 45 A1 test point locations, 53 A2 board removal, 40 A2 Interface Board, 44 A2/A3 block diagram, 55 A2S201, 45 A3 board removal, 41 A3 Front Panel, 44 ADC, 44 —B— bias voltages, 34, 35 —C— cal denied, 37 calibration, 37 calibration - post repair, 37 CC, 34 CC line regulation, 19 CC load effect, 19 CC load regulation, 19 CC loop, 46 CC noise, 20 CC- operation, 18 CC source effect, 20 CC_Detect*, 44, 46 CC_Prog, 45, 4
Index —M— manual revisions, 10 —N— notice, 5 —O— -OUT, 43 out of range, 37 OV_Detect*, 44, 47 OV_Prog, 45 OV_SCR*, 44, 46 —S— safety considerations, 9 safety summary, 3 schematic notes, 53 SCR, 46, 47 secondary interface, 44 self-test, 33 -sense, 43 sense switch, 46 serial number, 5 series regulator, 45 shunt clamp, 46, 47 status annunciators, 34 —T— —P— PARD, 16, 20 password, 37 performance test form, 21 performance tests, 14 PM_Inhibit, 47 power-on self-test, 33 primary interface, 44 printing, 5 prog
