BK PRECISION_85xx_manual 电路图.pdf

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1、 USER MANUAL 8500 SERIES DC ELECTRONIC LOADS Models 8500, 8502, 8510, 8512, 8514, 8518, 8520, 8522, 8524 to stop the short, you must press the On/Off key Note: When emulating a Short while in CV mode, the current software limit may trigger the DC load Input to turn Off, provided the current limit is

2、 reached. This does not affect the programmed settings and the DC load will restore the previously programmed values once the Short condition is removed. Battery test The battery test feature measures the time it takes for a battery voltage to drop to a specified value while drawing a constant curre

3、nt from the battery. When the voltage at the DC Loads terminals reaches the specified voltage, the test is ended and the integrated current (i.e., charge supplied by 8500 DC Load Series Version: February 4, 2009 Page 32 of 76 the battery) in ampere*hours (A*hrs) of the battery is calculated and disp

4、layed. To run a battery test, follow these steps: Key pressesDisplay I-set, enter current value with numerical keys, then press Enter. Set the DC Load to constant current mode and set the current you want to draw from the battery. (You may have to press the I-set key twice to be able to set the curr

5、ent value.) Shift + BatteryMIN VOLT= 0.10V This indicates youre being asked for the voltage level where the battery test will be over. Enter voltage level and press Enter. When you press Enter, the test will start. The CC annunciator will be on. or Shows the power level and the ampere*hours (A*hrs)

6、accumulated so far. When the battery voltage drops below the specified value, the test will turn off and you will see the OFF annunciator. or Display the total charge delivered by the battery in ampere*hours (A*hrs). Shift + BatteryTurns battery testing mode off. NOTE: you must make sure that you pr

7、ess Shift + Battery at the end of the test. Otherwise, the instrument will not respond to any key presses except or . Transient operation The transient condition allows switching between two different load values. There are three different types of transient operation. Continuous transient operation

8、 In continuous transient operation, the load is continuously switched between two load values. An example is shown in the following figure: 10A 5A Continuous Transient Operation 2.0ms3.0ms Note that this transient behavior works with any of the operation modes CC, CV, CW, or CR. Here are the keystro

9、kes used to setup this continuous transient condition: KeysDisplay I-setStandard display of voltage and current (or, youll be asked to enter a current value). 8500 DC Load Series Version: February 4, 2009 Page 33 of 76 KeysDisplay Shift + S-TranLEVEL A= X.XXXA You are being prompted for the first cu

10、rrent value. Press the 5 key for 5 A. EnterEnters the 5 A value, then displays WIDTH A = X.XMS. Youre being prompted for the duration of the 5 A load - press the 3 key for 3 ms. EnterEnters the 3 ms value, then displays LEVEL B= X.XXXA. You are being prompted for the second current value. Press the

11、1 and 0 keys to enter 10 A. EnterEnters the 10 A value, then displays WIDTH B = X.XMS. Youre being prompted for the duration of the 10 A load - press the 2 key for 2 ms. EnterEnters the 2 ms duration, then displays :CONTINUOUS, :PULSE, or :TOGGLED. Use the or arrow keys to display :CONTINUOUS. Enter

12、Returns to the standard display of voltage and current. To activate this continuous transient condition, press Shift + Tran, then press On/Off. The load will begin switching between the two Tran values with the timing you entered. Pulse transient operation In pulse transient operation, the load oper

13、ates at the A value that has been entered until a trigger is received. At the trigger, the load switches to the B value and stays at that level for the B timing value. Then the load switches back to the A value and stays there until another trigger is received. Heres an example: 10A 5A Pulsed Transi

14、ent Operation 10ms TWD 10ms TWD TRIGTRIG Here are the keystrokes needed to set up this example: KeysDisplay I-setStandard display of voltage and current (or, youll be asked to enter a current value). Shift + S-TranLEVEL A= X.XXXA You are being prompted for the first current value. Press the 5 key fo

15、r 5 A. EnterEnters the 5 A value, then displays WIDTH A = X.XMS. Youre being prompted for the duration of the 5 A load. In the pulse mode of operation, this width is ignored, so enter any convenient value. EnterDisplays LEVEL B= X.XXXA. You are being prompted for the second 8500 DC Load Series Versi

16、on: February 4, 2009 Page 34 of 76 KeysDisplay current value. Press the 1 and 0 keys to enter 10 A. EnterEnters the 10 A value, then displays WIDTH B = X.XMS. Youre being prompted for the duration of the 10 A load - press the 1 and 0 key for 10 ms. EnterEnters the 10 ms duration, then displays :CONT

17、INUOUS, :PULSE, or :TOGGLED. Use the or arrow keys to display :PULSE. EnterReturns to the standard display of voltage and current. To activate this pulse transient condition, press Shift + Tran, then press On/Off. The load will start at the A level of current you entered (5 A). Press Shift + Trigger

18、 to cause the load to switch to the B level of current (10 A). The 10 A current will last for the designated 10 ms, then switch back to the A level (5 A). NOTE: This example requires the :CONFIG:TRIGGER menu item be set to :IMMEDIATE. If set to :EXTERNAL, youd trigger the instrument with a high TTL

19、level signal on the trigger terminals on the rear panel. If set to :BUS, youd trigger the instrument with a software trigger. Toggled transient operation In toggled transient operation, the load starts at the stored parameter for the mode. When a trigger is received, the load switches to the B value

20、. When another trigger is received, the load switches to the A value. It stays at the A value until another trigger is received, at which point it switches to the B value. Further triggers cause the load to switch between the A and B values. Heres an example: 10A 5A TRG TRG Toggled Transient Operati

21、on Here are the keystrokes needed to setup this example: KeysDisplay I-setStandard display of voltage and current. Enter a value of 5 A (you may need to press the I-set key again). Press Enter. EnterEnters the CC modes value. The standard display is shown. Shift + S-TranLEVEL A= X.XXXA You are being

22、 prompted for the first current value. Press the 5 key for 5 A. EnterEnters the 5 A value, then displays WIDTH A = X.XMS. Youre being prompted for the duration of the 5 A load. In the toggled mode of operation, this width is ignored, so enter any convenient value. 8500 DC Load Series Version: Februa

23、ry 4, 2009 Page 35 of 76 KeysDisplay EnterDisplays LEVEL B= X.XXXA. You are being prompted for the second current value. Press the 1 and 0 keys to enter 10 A. EnterEnters the 10 A value, then displays WIDTH B = X.XMS. Youre being prompted for the duration of the 10 A load. . In the toggled mode of o

24、peration, this width is ignored, so enter any convenient value EnterDisplays :CONTINUOUS, :PULSE, or :TOGGLED. Use the or arrow keys to display :TOGGLED. EnterReturns to the standard display of voltage and current. To activate this toggled transient condition, press Shift + Tran, then press On/Off.

25、The load will start at the value you entered for A (5 A). Then press Shift + Trigger to cause the load to switch to the B level of current (10 A). The next trigger will cause the load to shift back to the A level (5 A). Subsequent triggers repeat this behavior. NOTE: This example requires the :CONFI

26、G:TRIGGER menu item be set to :IMMEDIATE. If set to :EXTERNAL, youd trigger the instrument with a high TTL level signal on the trigger terminals on the rear panel. If set to :BUS, youd trigger the instrument with a software trigger. Toggle between two test values When you have entered A and B values

27、 through the Shift + S-Tran menu, those values are available to you at the front panel. Suppose you set the instrument to operate in CC mode at a current of 1 A. If the transient A level was 5 A and the transient B level was 10 A, you can set the instrument to the A level by pressing Shift + A. The

28、load has to be on and cannot be in transient condition (i.e., the TRAN annunciator must not be lit). Otherwise, the A value will be stored as the CC modes current. Similarly, Shift + B causes the B value to be stored as the CC modes current. The load can be on or off for this to work. Lists (dynamic

29、 condition) Transient operation is used for simple step changes in load values. More complicated dynamic behavior of the load can be obtained through the use of lists. Lists are a sequence of load value and duration pairs. Lists are the logical extension of transient operation. To illustrate the use

30、 of a list, well create a list that runs the following constant current profile on a power supply: Trigger 1023 45 List count=1List count=2 List sequence This list is characterized by the following current/duration pairs 8500 DC Load Series Version: February 4, 2009 Page 36 of 76 Current, ADuration,

31、 msBetween times 310000 and 1 08001 and 2 25002 and 3 03003 and 4 65004 and 5 This list has 5 steps, located at the transitions 1 through 5. The first duration, 1000 ms, occurs after the triggered event. Subsequent durations are from the previous transition to the current transition. Here are the ke

32、ystrokes to set up this list: KeysDisplay Shift + Menu:CONFIG :LIST SET Enter:MODE SET EnterSelect :LIST mode. This will cause the LIST annunciator to turn on. Enter:MODE SET :EDIT LIST FILE Enter:CURRENT LIST EnterSelect :REPEAT. EnterLIST COUNT= N How many steps this list has. Enter the number 5.

33、5 EnterCOUNT 1= X.XXA Set the current for the first step. Enter 3. 3 EnterCOUNT 1= X.XXMS Set the duration for the first step. Enter 1000. 1000 EnterRepeat the current and duration entry for the following 4 steps. EnterSTORE LIST FILE1 The 1 is underlined, indicating you can enter a number to specif

34、y the file (i.e., block of EEPROM) to store this list to. Choose a number via the keypad or the knob. You can choose any number between 1-8. Enter:EDIT LIST FILE Esc EscStandard display First, press the On/Off key. The load will sink the current that is stored as the CC mode parameter (set it to 0 A

35、 if you dont want an initial current). Then press Shift + Trigger to have the list start executing. Should you wish to have the list only execute once after the trigger, you can edit the list to use :ONCE instead of :REPEAT. To exit List mode press the Shift and Trigger key Test files Test files are

36、 a generalization of lists - they let you generate a sequence of tests using different 8500 DC Load Series Version: February 4, 2009 Page 37 of 76 modes, mode parameters, and durations. They are useful for executing a set of tests on a device, then displaying whether the tests passed or failed. We w

37、ill illustrate how to use test files by a short example. Suppose we have a small AC to DC power supply (a wall-wart) and we want to set up an acceptance test for a number of these devices. Our test will consist of two steps: 1.Set the DC load to constant current mode to draw the rated current of 0.3

38、5 A from the device. The output voltage of the device at the rated current must be between 4.4 volts and 4.6 volts. 2.When the device operates into a short, the supplied current must be larger than 2.0 A. KeysDisplay Shift + Menu:CONFIG :LIST SET Enter:MODE SET :EDIT TEST FILE EnterMAX CURR= 3.000A

39、Set the maximum current to 2.5 A 2.5 EnterMAX VOLT= 18.00V Set the maximum voltage to 5 V 5 EnterMAX POWER= 150.00W Set the maximum power to 15 W 15 EnterTEST COUNT= 6 Our test will consist of two steps, so we enter 2. You can enter up to 20 steps. 2 EnterCONST CURRENT Since our first test is in con

40、stant current mode, well just press Enter to select this mode. EnterSET 1= 0.210A This is the prompt for the constant current value. We set it to 0.35 A. .35 EnterSHORT OFF We can turn a short on or off at this step. Here, we want short off, so we just press Enter. EnterREADBACK V Were being prompte

41、d for what parameter to read back and check. We want voltage, so we press Enter. EnterMIN 1= 5.80V We want the minimum voltage read back to be at least 4.4 V. 4.4 EnterMAX 1= 6.15V The maximum value well allow is 4.6 V. 4.6 EnterDELAY 1= 1.0 This delay time is how long to wait before making the read

42、back measurement. If you set it to 25.5 seconds, the test will halt at this point, requiring you to press Shift + Trigger to continue the test. Well use 1 second. 1 EnterCONST CURRENT Were being prompted for the mode to use for the next step. Well again use constant current, so well press Enter (thi

43、s step will also be a short, so the mode doesnt really matter). EnterSET 2= 5.000A Well set the current to 2.5 A, which is the maximum current weve allowed for this test. 8500 DC Load Series Version: February 4, 2009 Page 38 of 76 KeysDisplay 2.5 EnterSHORT OFF We select short on and then press Ente

44、r. EnterREADBACK A We want to readback the current, so we press Enter. EnterMIN 2= 4.950A Our minimum value is 2.0 A. 2 EnterMAX 2= 5.050A We choose 2.5 A as the maximum value. 2.5 EnterDELAY 2= 3.0 Well wait 2 seconds for the maximum current. 2 EnterSTORE TEST FILE1 The 1 is underlined, meaning you

45、 can choose which test file number to store this test to. You can choose any number between 1-8. Here, we will use 1, so just press Enter. EnterEDIT TEST FILE Esc EscExit the menu. The normal display is shown (V and A). The test file has been created and saved in file position 1. Now we will run the

46、 test on the device. KeysDisplay Shift + Menu:CONFIG :LIST SET Enter:MODE SET :CALL TEST FILE EnterRECALL 1 Were being prompted for which file number to recall. Since we saved to file number 1, we just press Enter. EnterCALL TEST FILE The test file is now loaded, so we return to the normal display.

47、Esc EscExit the menu. The normal display is show (V and A). Shift I-setNAME:TEST FILE 1 Weve entered automatic testing mode. The display is showing which test file were using. Shift TriggerThis starts the test. Youll see the values sequentially displayed. Then youll either see PASS or FAULT. You can

48、 press Shift Trigger again for another test run or press Esc to return to the normal display. EscReturn to the normal display. Triggering Triggering is used with the transient and dynamic conditions to allow synchronization of the DC Loads behavior with other events. There are three types of trigger

49、s you may use (set in the CONFIG:TRIGGER SOURCE menu): Trigger TypeExplanation IMMEDIATEAn immediate trigger is created by pressing Shift + Trigger on the 8500 DC Load Series Version: February 4, 2009 Page 39 of 76 Trigger TypeExplanation front panel keys. EXTERNALAn external trigger is a TTL high signal applied to the Trigger connection on the back panel. This TTL signal must last for more than 5 ms. A trigger applied to this input can be used to change settings (voltage,