DVC-4

CLASSICAL SHOCK CONTROLLER

ON-LINE MANUAL

Product Description       	File Menu

Vibration Testing Tutorial           	System Menu

Specifications	Inputs Menu

Installation   	Shock Setup Menu

Screen Descriptions	Test Setup Menu

Operation                                  	Test Run Menu

Service	View Menu

Updating Software	Tools Menu

Calibration Procedure	Help Menu

Connector Pin-out, DB-37

Connector Pin-out, Remote

Revised 1/2001


PRODUCT DESCRIPTION

 The DVC-4 is a vibration control system for use with IBM compatible personal computers; it is essentially a programmable digital waveform generator and data acquisition system with sophisticated control and analysis software. It is shipped along with a computer interface card, Windows 3.1/95 software on 3-1/2" disks  and a 2' cable, although a complete system would also have a shaker, amplifier, and an accelerometer at a minimum.

 It is designed for controlling a wide variety of classical shock tests with ease of use and automated record keeping; classical shock tests are those defined by geometric shaped shock waveforms ( e.g. sine, triangle, rectangular, parabolic, etc.).

The computer interface card installs in the computer in an ISA or PCI slot, depending on the model supplied; PCI will become the standard. It has a 24 line 8255 type digital interface. Several vendors cards are used, but all follow the ComputerBoards/Cyber- Research PCI-DIO24 connector interface. The ISA card may be set to any free I/O address space with jumpers on the card, with Hex 300 is the suggested starting point; the PCI card address is set by the Windows plug-and-play software, and the address must be checked after installation. The software is set with Hex 6200 as the default value ( see Software Installation ).

The DVC Controller module connects to the computer interface card via a short DB-37 female- female cable, and all drive and feedback connections are made with the BNC connectors. A 6 pin Molex type connector is available for remote control of the System. The DVC Controller can be configured for either 2 or 4 channel operation in Sine, Random, or Classical Shock modes; the software automatically detects the Controller configuration and enables the appropriate features.

Persons new to vibration testing should read the tutorial section to gain a better knowledge of the processes and terms used. Additional information is available on the web site www.vibrationworld.com, which is supported by the manufacturer.


VIBRATION TESTING TUTORIAL

 Vibration testing is the process of applying a controlled amount of vibration to a test specimen, usually for the purposes of establishing reliability or testing to destruction. In practice the test article is securely mounted on a shaker table or actuator, which may be operated by electro-dynamic or hydraulic force; typically hydraulic force is used at very low frequencies because of the large displacements involved, and electro-dynamic force is used where higher frequencies are involved.

An electro-dynamic shaker is a linear motor: a moving coil in a fixed magnetic field that is the same principle used in the construction of a loud-speaker. The magnetic field is generated by either permanent magnets or by DC current in a field coil, and audio power is provided by an amplifier of suitable rating, typically about 10 watts of audio/ pound force generated.

Some type of signal source is necessary to drive the amplifier, and an accelerometer is needed to measure the vibration response of the test article. Accelerometers are referred to as Integrated, meaning they have a built-in amplifier and need a current source for power, or Charge type, requiring an external charge-converter to make a usable signal from their output. If the test article is large, then the response may vary across its surface and multiple accelerometers may be used and the outputs averaged.

The overall response curve is usually VERY non-uniform due to the response curves of the amplifier and shaker, and mechanical resonances of the shaker, test article, and mounting fixtures. To cure this, a controller us used to servo the actual measured response to the desired response curve. Controllers may be rack-mounted analog instruments or digital computer-based products.

The signal source usually attempts to simulate the real-world environment that the test article will operate in. Two methodologies are commonly used: Swept-sine and Random testing. In the Swept-sine approach the frequency is swept back and forth with amplitudes corresponding to the desired test levels. In Random testing the frequency spectrum of a noise source is shaped to represent the environment that the article will operate in. An additional test approach is Classical shock testing where the article is subjected to one or more high level shock pulses; this is similar to a one time drop-test that might occur in shipping. In all three approaches the test level can be increased until destruction occurs, thus establishing the safety margins.


SPECIFICATIONS

INPUT CHARACTERISTICS:

INPUT CHANNELS:  One control and one monitor channel.

INPUT SENSITIVITY:  Settable from 5 to 1000 MV/G, 20 Vp-p max input.

CURRENT SOURCES:  Two 4 MA , 18 VDC compliance, software selectable.

OUTPUT CHARACTERISTICS:

OUTPUT SIGNAL:  1024 point  filtered analog drive waveform.

DRIVE LEVEL:  16 Vp-p maximum.

PEAK LIMITING:  User settable from 0 to 16 Vp-p maximum drive output.

DYNAMIC RANGE:  > 60 Db.

CONTROL CHARACTERISTICS:

WAVEFORMS:  Half-sine, triangle, trapezoidal, rectangular, initial or terminal 	peak saw-tooth, quarter-sine, parabolic cusp or sine-burst.

WAVEFORM GENERATION:  12 bit x 1024 points with 12 bit amplitude 	scaling.

PULSE DURATION:  1 to 100 Msec.

MODES:  Single pulse or repetitive pulses, with settable pulse count and rep rate.

TEST LEVEL:  0.5 to 200 G-peak.

POLARITY:  Positive or negative pulses.

CONTROL PROFILES:   Up to 99 shock profiles may be saved and recalled from disk.

CONTROL ACCURACY:   +/- 1 Db typical.

SAMPLING FREQUENCY:  1.28 Khz to 10.24 Khz.

EQUALIZATION TIME:  < 10 seconds for low level equalization of system 	transfer function.

REMOTE CONTROL (Optional):  Inputs for Equalization, Pretest, Start, and 	Abort; 5 volt logic levels activated by switch closure to ground.

TEST ARTICLE PROTECTION:

ABORT / ALARM LIMITS:  User selectable from 1 Db to 99 Db.

OVERALL LIMITS:  Overall D, V, A limits settable by user.

CONTROL SIGNAL LOSS:  Open loop detector check.

PRETEST LIMITS:  Settable by user.

EQUALIZATION:  Low level equalization of system.

MANUAL ABORT:  From mouse, keyboard or optional remote panel.


TEST DOCUMENTATION:  Any of the following screens can be viewed or printed 	out on a printer:

TEST PROFILE:  Control profile and predicted velocity and displacement

EQUALIZED SYSTEM RESPONSE:  Response acceleration, velocity and 	displacement.

DRIVE OUTPUT:  Output analog drive waveform of card of card.

SHOCK RESPONSE SPECTRUM:  Equivalent response of a single degree of 	freedom system to the acceleration spectrum.

SYSTEM REQUIREMENTS:

COMPUTER:  Pentium 70 or better with VGA display, 16 Mb RAM and 6 Mb of hard disk space required.  A Pentium 166 or faster is recommended.

POWER REQUIREMENTS:  Powered by computer buss, < 10 W required.

SIZE:  1.5H x 7.25W x 15D Controller box with standard 1/3 AT size PC interface card ( 4.5" x 4.5" ).

CONNECTIONS:  Via DB-37 connectors and cable from computer to Controller box and BNC connectors to signals; optional remote control connections via 6 pin Molex connector.


INSTALLATION

HARDWARE  INSTALLATION.  Install the DVC-4 computer interface card in a PCI expansion card slot of an IBM compatible personal computer of Pentium grade or better with a VGA display; a hard disk is necessary with Windows software. A Pentium 166 or better is recommended for superior performance. The card address is automatically set by the Windows plug-and-play software and the software must be set to the same value used by the system during installation; if an additional card is installed in the computer later, the address might be changed and the software must be changed accordingly in the System configuration menu.

Connections  to  the  shaker system  are  through  the  BNC connectors  on  the front of the  controller box; a 2' DB-37 cable is used  to connect from the computer to the controller box.  Simple installations require only a coax for Servo Out to the amplifier drive input and a BNC cable from the Channel #1 input on the controller box to the accelerometer.  Remote control is accomplished by switch closures to ground by any of the 4 Remote Control pins on the Remote connector; refer to the connector pin-out diagram.

SOFTWARE INSTALLATION.  There are two programs to install on the computer: one for the PCI interface card installed inside the computer called INSTACAL, and the DVC16DSC software for vibration control; each comes standard on floppy disks.

After the hardware installation above, turn on the computer and the system should detect a new PCI card and ask for the driver disk; insert disk #1 of INSTACAL and proceed with the default instructions. The card address that was used by the system can be determined three ways: one is to start INSTACAL from START|PROGRAMS| (COMPUTERBOARDS or CYBER-RESEARCH) and select CONFIGURE from the INSTALL menu. The other is in the SYSTEM item in START|SETTINGS| CONTROL PANEL; select the DEVICE MANAGER tab, click DAS COMPONENT, then PCIDIO24, then properties, then resources to view the base address ( the first number of the range is the address ). The third is to use the Auto-Detect Address function on the System menu.

The DVC16CSC.EXE software comes on a set of 2 floppy disks and requires about 6 mb of hard disk space. The disks also contains some sample profiles; using the program in the Demo mode is highly recommended as a training tool to get used to the software without risking possible damage to the equipment. Load by inserting disk #1 into the disk drive and typing SETUP; follow the instructions and it should automatically install on the hard drive. The directory can be changed during the setup if desired.


SCREEN DESCRIPTIONS

The CSC Windows software features a Control Panel screen and many windows offering expanded information; a description of each of these screens follows.

 CONTROL PANEL.  This is a "virtual instrument" screen that mimics a real instrument with large digital displays, a plot of the response, LED type indicators and a monitor section that displays all system parameters. The operation is controlled either by the mouse or from the keyboard with single key keystrokes; the active keys are listed in the HELP Keyboard menu; for example "S" is start, "A" is abort, etc.  The operator has full control of system operation with the mouse or a few easily remembered keys. Operation is "automatic" with the controlled response following the desired profile. If an abort condition is encountered the Stop button will change from green to red and one of the following messages appear: OPEN LOOP, LOW GAIN, OVER-TEST, >D-LIMIT, >V-LIMIT, or >A-LIMIT.

MENU BAR.  If the setup conditions of the test need to be checked or changed, or files saved, loaded or printed, use the Menu Bar to list all of the setup conditions and the profile to be run. Use the mouse or up/down arrow keys to move the cursor to the item to be changed and click or press enter and the default value will be displayed. If that is OK, click on OK or press enter and nothing is changed. If you wish to make a change, type in the new value and enter; if it is out of bounds it is thrown out. If the value is a choice, (e.g. SLOW, ON, etc.) click on the desired choice.The Menu Bar is divided up into categories; selecting one will drop down a menu listing the items that the user can set. The categories are listed below:

TEST PROFILE SCREEN.  This graphic screen is a plot of the calculated acceleration response Vs time, along with the predicted velocity and displacement plots, if enabled in the setup; select the Test Profile plot in the VIEW menu. The predicted acceleration will be displayed in red and the velocity in yellow and the displacement will be displayed in purple. Abort limits will be displayed in white also if they have been checked.

Selecting other choices in the VIEW menu at any time can alternate the four plots. The plots can be labeled in either English or Metric units and scaled up and down in both amplitude and time-scale with the arrow keys or arrow buttons at the plot origins..

SYSTEM RESPONSE PLOT SCREEN.  This graphic screen is a plot of the actual recorded system response to the applied shock, along with the velocity and displacement curves that would accompany that acceleration waveform if enabled; select CH#1 RESPONSE in the VIEW menu. The plot can be labeled in either English or Metric units and be scaled with the arrow keys or arrow buttons at the plot origins. The acceleration is plotted in red, the velocity in yellow, and the displacement in purple. The plot can be zoomed in/out using the VIEW menu commands or the X,x,Y,y hotkeys.

DRIVE WAVEFORM.  The drive waveform is computed from the results of the equalization process and is the analog voltage waveform needed to produce the desired acceleration response; it generally has a largely triangular shape to overcome the velocity component of the shaker. The waveform is stored in a look-up table as 12 bits x 1024 points and clocked out at the sampling rate; the overall amplitude is then scaled by another 12 bits of amplitude resolution.

SHOCK RESPONSE SPECTRUM.  The shock response spectrum, or SRS, is the predicted response of a set of single degree-of-freedom masses to the applied shock, and is thought to better simulate the results of a shock in a real physical object. It dates back 50 years when shocks were measured by a set of various length vibrating reeds with pencil leads attached; the lengths of the pencil lines were plotted to produce a plot of the effect of the shock over the frequency range. It is still popular and MIL-STD-810 explains the relationship between SRS and common shock waveforms. Currently it is calculated by taking a FFT of the acceleration waveform and entering it into a formula simulating Q=10 resonances at each spectral line.


FILE MENU

A)  OPEN PROFILE- Opens a Windows dialog box to select the path and name of the previously saved test profile to be loaded. Opening a profile loads all of the setup parameters with it. Profiles are normally named as DVCFILEC.*, where * is a number from 000 to 999, but any 8 character name with a 3 character extension can be used instead.

B)  OPEN REPORT- Opens a Windows dialog box to select the path and name of the previously saved test report to be loaded. Opening a report loads all of the setup parameters with it. Reports are normally named as DVCTESTC.*, where * is a number from 000 to 999, but any 8 character name with a 3 character extension can be used instead.

C)  SAVE PROFILE- Opens a Windows dialog box to select the path and name where the test profile is to be saved. Saving a profile saves all of the setup parameters with it. Profiles are normally named as DVCFILEC.*, where * is a number from 000 to 999, but any 8 character name with a 3 character extension can be used instead.

D)  SAVE REPORT- Opens a Windows dialog box to select the path and name where the test report is to be saved. Saving a report saves all of the setup parameters with it. Reports are normally named as DVCTESTC.*, where * is a number from 000 to 999, but any 8 character name with a 3 character extension can be used instead. Note: the response plot is saved with the current background color; if the report will be printed out later, it may be desirable to use the white background to save ink.

E)  EXPORT TEST DATA- Exports the test setup parameters and test data into an Excel-format file; the suggested naming convention is DvcDataC.*, where * is a user assigned number. Refer to the application note on www.vibrationworld.com for full details on the file format.

F)  PRINTER SETUP- Opens a Windows dialog box to select printer to be used and it's setup options.

G)  PRINT- COLOR- COLORS | MONOCHROME- Sets the colors outputted to the printer to either the same colors as the screen, or all black for high contrast printouts. With some printer drivers this will automatically choose either color or black & white printing; others require setting the printer to color mode in the printer setup.

H)  PRINT REPORT- Prints the report on the default printer, or the one selected in Print Setup.

I)  EXIT- Opens a Windows dialog box to confirm your intention of exiting the program.


SYSTEM MENU

A) AUTO-DETECT ADDRESS- Windows assigns the addresses to plug-n-play PCI cards. This function attempts to find the address assigned to the installed PCI interface card. Enter this address as the base address in the System menu, and save the changes in the DvcFileC.000 default profile.

B)  BASE ADDRESS- Dialog box to set the computer interface card address, for PCI cards the Windows plug-and-play software sets the address, which is typically 6200 Hex. This number must match the system setting for the controller to work!

C)  UNITS: ENGLISH | METRIC  Selects the units to be used, either English or Metric (mm.,cm/sec.,m/sec^2.).

D)  MAX. DISPLACEMENT- Dialog box to set the maximum displacement allowable to protect the shaker.

E)  MAX. VELOCITY- Dialog box to set the maximum velocity allowable to protect the shaker.

F)  MAX. ACCELERATION- Dialog box to set the maximum acceleration allowable to protect the shaker.

G)  LOW GAIN TRIP POINT- Dialog box to set the Low Gain error message trip point.

H)  OPEN LOOP TRIP POINT- Dialog box to set the Open Loop error message trip point.

I)  CALIBRATION FACTORS, CH#1 GAIN:  Dialog box to reset the channel #1 scale calibration factor. The nominal value is 1.00. NOTE: Altering this value will affect the system accuracy; this should be done as part of the calibration procedure.

J)  UPDATE CALIBRATION FACTORS:  Saves the current calibration factors in the   file DVC16CAL.DAT.


INPUTS MENU

A)  CH#1 SENSITIVITY- Dialog box to set the CHANNEL #1 sensitivity from 5-1000 MV/G.

B)  CH#2 SENSITIVITY- Dialog box to set the CHANNEL #2 sensitivity from 5-1000 MV/G.

C)  CH#1 CURRENT- Select the CHANNEL #1, 4 MA current source, either ON or OFF.

D)  CH#2 CURRENT- Select the CHANNEL #2, 4 MA current source, either ON or OFF.

E)  ACCELEROMETER: MODEL# | SERIAL# - Opens Windows dialog boxes to record the accelerometer model # and serial #.

F) 	REMOTE CONTROL- Select whether the Remote control inputs are activated or disabled.

G)  DLL CONTROL- Enables control of the Dvc16DSC.Exe software by another program through the device driver ( Dvc16Dll.dll ). The standard Remote Control functions are accessible; refer to the application note on www.vibrationworld for full details and examples.


SHOCK SETUP MENU

A)  PULSE SHAPE: HALF-SINE | TRIANGLE | TRAPEZOIDAL | INITIAL PEAK SAWTOOTH | TERMINAL PEAK SAWTOOTH | QUARTER-SINE | PARABOLIC CUSP|SINE-BURST- Choose the pre-defined geometric pulse shape.

B)  PULSE AMPLITUDE-  Opens a dialog box to set the test peak amplitude from 0.5 to 200 G's.

C)  PULSE DURATION-  Opens a dialog box to set the pulse duration from 1 to 100 Msec.

D)  POLARITY:  POSITIVE | NEGATIVE-  Set the pulse polarity.

E)  REPETITION MODE: SINGLE PULSE | REPETITIVE-  Set the mode for either a single or multiple pulses.

F)  SAMPLING FREQUENCY: 1.28 | 2.56 | 5.12 | 10.24 KHZ.-  Normally set to 5.12 Khz for pulse widths of around 10 Msec


TEST SETUP MENU:

A)  CONTROL MODE- Selects between normal Automatic Mode and Manual Mode. In Manual Mode Equalization is disabled, an Up/Down arrow control appears to set the output level, and the input channels function as general purpose data-acquisition channels.

B)  EQUALIZATION LEVEL-  Opens a dialog box to set the equalization level in G's; the default value is 1.0.

C)  PRETEST LEVEL-  Opens a dialog box to set the pretest level in -Db.

D)  ABORT LIMITS- Opens a dialog box to set the abort limits in Db. The upper and lower limits are symmetrical.

E)  #PULSES-  Opens a dialog box to set the total number of shock pulses.

F)  REPETITION RATE- Opens a dialog box to set the repetition rate of the shock pulses in seconds/pulse.

G)  MAX DRIVE LEVEL-  Opens a dialog box to set the maximum output level in volts peak.

H)  TITLE-  Allows the user to enter a title to be used with the plots and saved with the test.

I)  AUTO PRINT- Prints the test report at the conclusion of a test if turned on (checked in the menu).

J)  AUTO SAVE- Saves the test report at the conclusion of a test if turned on

(checked in the menu). The user will be prompted for the path and filename at the start of the test.

K)  DEMO ROUTINE- Runs the demonstration program if checked; if the BussCheck detects that the card is not installed or not communicating the program will be placed in the Demo mode. The Demo mode runs simulated tests, but all normal features are active.


TEST RUN MENU

A)  EQUALIZE-  Starts the process to equalize the system gain by using low level pulses as set in the Test Setup menu; same action as clicking on the Equalization button.

B)  PRETEST-  Generates a shock pulse at the Pre-Test level as setup in the Test Setup menu; same action as clicking on the Pre-Test button.

C)  START-  Generates a shock pulse at the full test level or starts a series of pulses as setup in the Test Setup menu;; same action as clicking on the Start button.

 D)  ABORT-  Aborts the test and resets the pulse counter; same action as clicking on the Abort stop sign button.


VIEW MENU

A)  TEST PROFILE-  Plots the test that has been previously setup; the items that are plotted depend on the selections made below.

B)  CH#1 RESPONSE-  Plots the channel #1 test article response to the test that has been previously setup; the items that are plotted depend on the selections made below.

C)  CH#2 RESPONSE-  Plots the channel #2 test article response to the test that has been previously setup; the items that are plotted depend on the selections made below.

D)  DRIVE WAVEFORM-  Plots the drive waveform that will be used to generate the desired shock pulse; it usually bears little resemblance to the shock pulse shape due to the system transfer function.

E)  SHOCK RESPONSE SPECTRUM-  .  Plots the shock response spectrum, or SRS of the CH#1 response. The SRS is the predicted response of a set of single degree-of-freedom masses to the applied shock, and is thought to better simulate the results of a shock in a real physical object

F)  ACCELERATION-  Plots the acceleration curve if checked.

G)  VELOCITY-  Plots the velocity curve if checked.

H)  DISPLACEMENT-  Plots the displacement curve if checked.

I)  ABORT LIMITS- Plots the abort limits if checked.

J)  REFRESH SCREEN- Redraws the screen to remove clutter.

K)  PLOT BACKGROUND- BLACK- Selects black as the plot background color;   black views the best on-screen, but uses excessive ink during printing when using COPY TO CLIPBOARD to export into other applications.

L )  PLOT BACKGROUND- WHITE- Selects white as the plot background color; white doesn't view as well as black on-screen, but uses less ink during printing when using COPY TO CLIPBOARD to export into other applications.

M)  X-AXIS SCALE- ZOOM IN- Expands the scale of the plot X-axis one step.

N)  X-AXIS SCALE- ZOOM OUT- Contracts the scale of the plot X-axis one step.

O)  Y-AXIS SCALE- ZOOM IN- Expands the scale of the plot Y-axis one step.

P)  Y-AXIS SCALE- ZOOM OUT- Contracts the scale of the plot Y-axis one step.


TOOLS MENU

A)  COPY TO CLIPBOARD- Copies the plot onto the system clipboard to be  incorporated into other applications. . Press the Print-Screen key to copy the entire screen to the clipboard. The plot background color will be that set in the VIEW| PLOT BACKGROUND menu.


HELP MENU

A)  KEYBOARD- Displays the keyboard hot keys that control operation without a mouse.

B)  ONLINE HELP- Opens a Windows help file containing the on-line manual

C)  ABOUT SOFTWARE- Displays the version number of the software and pertinent phone numbers. Also displays the version number of the DLL driver.

D)  ABOUT HARDWARE- Reads the Controller configuration registers and displays the serial # and lists the hardware capabilities.


OPERATING INSTRUCTIONS

SHOCK CONTROLLER OPERATION.  The Setup items should be checked over and modified as necessary; review the Setup parameters by clicking the appropriate menu item. The PULSE SHAPE and DURATION should match that of the test being run, e.g. 11 Msec Half-Sine. Set the AMPLITUDE and POLARITY as desired and the TOTAL pulse COUNT; if the count is >1 the REP RATE can be set in seconds/pulse. The ABORT LIMITS can be set from 1 to 99 Db over-test and the SAMPLING RATE varied if either a longer time window or more resolution is needed. The level used for EQUALIZATION can be changed, as well as the PRE-TEST LEVEL, if there is reason to do so. The INPUT sensitivity should match those of the accelerometer used and the CURRENT SOURCE turned on if needed.

Check that the shock numbers are indeed what you wanted by viewing it in the Test Profile plot screen.

A test can be run from either the Predicted Performance or the System Response Plot Screens. Turn the amplifier gain up and click on the Equalize button or press "E" and the system should perform a low-level equalization and display a confirmation message.

Start the test by clicking on START or pressing (S) and the response will be displayed in red in the CH#1 Response plot screen; if the system was not previously equalized, it will do so first at this time. Click on the ABORT stop sign or press (A) to stop a test.  If a hard copy is desired, click Print in the File menu.

Profiles can be stored or read from disks with the SAVE PROFILE and OPEN PROFILE items in the FILE menu; the same with test results using SAVE REPORT and OPEN REPORT; the default profile and setup is stored in DVCFILEC.000 and will be used unless the file cannot be found. Profiles are saved in the format DVCFILEC.XXX unless changed; note that ALL setup parameters are stored with the profile.

If there are any problems with running a test or control accuracy, then the controller self-check described in SERVICE section B should be run.


SERVICE

TROUBLE-SHOOTING.  The controller is usually blamed for problems in vibration test systems, when in fact controllers rarely ever fail, and setup and cabling are usually the actual problem. The controller self-check is the best way to verify proper operation of the controller. If you are unable to locate the problem please have your serial # from the HELP|ABOUT HARDWARE menu, software and DLL versions from the HELP|ABOUT SOFTWARE menu, and equipment description ready before calling for technical support.

A )  BUSS-CHECK FAILS. Most likely the system address for the PCI computer interface does not match the setting in the SYSTEM|ADDRESS menu item; refer to the Software Installation section for instructions on checking the settings.

B )  CONTROLLER SELF-CHECK.  Connect the SERVO OUT to CH#1 input with BNC cables and "tee"s and run a test, preferably the default 15G 11 Msec half-sine one. Press "E" and the controller should equalize. Press "S" and a shock pulse should be generated and captured.  If it wont control well there may be other installed programs interrupting the process or a very slow CPU; try closing all other applications or using a lower sampling rate and see if that controls properly.

C )  POOR ACCURACY. Run the self-check in section B; if the plot inaccuracies exceed +/- 1 Db (10%) then something is wrong and must be found before real tests can be run. If erratic errors are observed, check for ground loops, excessive cable lengths, loose connections, or other noise-inducing problems.  Plug all instrumentation into the same 115V circuit as the computer is plugged into.

D )  WON'T PRINT. The wrong printer might have been selected in Print Setup.

E )  SCREEN LOCKED UP. Communication problem; check that both the address of the card and software are the same, that the card is firmly seated in the PC connector,  and that no other option card occupies the same address. Try changing the address, closing all other applications including screen savers or removing other cards to check for a conflict. .

F )  NO SHOCK OUTPUT OR LOW GAIN MESSAGE. Check that the cables are securely connected and that the amplifier gain was turned up and the field is on if applicable.

G )  OPEN LOOP MESSAGE APPEARS. Check that the current source is turned on if an integrated type is used, the cables are securely connected, and the amplifier gain turned up.

H )  SHAKER OVERDRIVES. No feedback; check accelerometer mounting, cables, and that the current source is turned on. Check that the velocity and displacement in the predicted performance plot are safely within system limits. Also, the pre- and post- pulse compensation have relatively low frequency components, and compensation may not be correct if the amplifier is not DC coupled or at least has a very low cutoff frequency.

I )  WON'T READ PROFILE. Check that the profile is stored on the default drive and in the current directory.

J )  >D-LIMIT, >V-LIMIT, or >A-LIMIT MESSAGE APPEARS. The system limits that were set up in the System menu have been exceeded; check that the limits were properly set and that the test levels are not exceeding the limits.

K )  WINDOWS PROBLEMS. The DVC-4 software is supplied in 16 bit Windows 3.1/Windows 95 format; be sure that you are using the right program to match the computer operating system. Windows NT is not currently supported.

L )  WRONG POLARITY PULSE.  Switch the leads from the shaker coil to the amplifier.


UPGRADING VTS SOFTWARE

The Setup disks contain approximately 25 files in compressed ( zipped) format; most of them are Microsoft Windows shared files that are necessary for the program to run, but do not change with program upgrades. In fact the only files that change are the .EXE file ( named CSC16.EXE for Shock ) and the driver ( DVC16DLL.DLL ); to upgrade is a simple matter of copying a new version over the old one. Setup de-compresses ( un-zips ) the files when installing them so the un-zipped version must be used in upgrades.

The files are normally placed in a directory or folder named C:\DVCShell; locate and open the folder using Explorer in Win 95/98 or File Manager in Win 3.1 and identify the .EXE file ( approximately  150K in size ).

Insert the new disk and in Win 95 Explorer click A Drive, select the new file, then click EDIT and then COPY;  scroll down to the previously located folder and click to open it; now Click EDIT and then PASTE and you will be asked if you want to copy the new one over the old one, and click YES. The new file will replace the old one and you are finished.

The procedure is similar in Win 3.1 File Manager.

The latest versions of the software are always available for downloading from the Internet; the WEB site URL is listed in the HELP|ABOUT SOFTWARE menu message.

Additional information is available on the web site Error! Reference source not found. which is supported by the manufacturer.


CALIBRATION PROCEDURE

DVC-4  CLASSICAL SHOCK CALIBRATION PROCEDURE:

1.	TEST EQUIPMENT REQUIRED:

1.1:  Personal Computer, Pentium or better running Windows 95.

1.2:  Digital Voltmeter, true RMS reading.

1.3:  Low-current shunt (e.g., 100 ohm or 1K-ohm 1% resistor), or DC current reading DVM.

1.4: BNC cables and "tee"s.

     NOTE: The Fluke 8060A true RMS Multi-meter meets all requirements of sections 1.2-1.3.

2.1: The DVC is a digital vibration controller that uses a PCI or ISA expansion card for the computer interface; it performs the functions of signal generation and control of a shaped-waveform generator and analyzer; there is also a switch-able accelerometer power supply on the input. There are no adjustments on the system ; all tests are of a verification nature. The card should be installed in a personal computer and the cable connected to the DVC connector in the rear of the chassis. The computer should be turned on and the DVC Shock software should be loaded in, which should come up in the CONTROL PANEL screen mode.

5.	CURRENT SOURCE TESTS:

3.1: Connect a DC current reading DVM, or precision resistor and DVM from Channel #1 Input to ground: a BNC cable with BNC-Banana jack adapter is a convenient way to accomplish this.

3.2: Activate the channel #1 current source with the Inputs | Ch#1 Current menu selection; click on the menu item to turn on the current source. Verify a DC current flow of 4.0 +/- 0.5 MA on the Input.

6.	PERFORMANCE VERIFICATION:

4.1: "Tee" the Ch#1 INPUT to the SERVO OUTPUT and set up a 15 G-peak, 10 Msec HALF-SINE test in the SHOCK SETUP menu, and 6 Db Pretest in the TEST SETUP menu. Turn the current source OFF in the INPUT menu.

4.2:  Click on the EQUALIZE button and a "system equalizing- please wait" message will appear at the bottom of the screen; after ten seconds it should be replaced with a "Equalized" message.

4.3:  Click on the START button and a shock pulse test should successfully complete and the results be displayed; repeat several times and verify that the peak amplitude is 15 +/- 1 G. If out of tolerance, adjust the calibration factor in the SYSTEM|CAL FACTORS|CH#1 GAIN menu until within tolerance and save the results.

4.4:  Click the PRE-TEST button and verify that the test is successfully completed at the level reduced by the pre-test vales ( 50% for 6 Db ); repeat several times.

This completes the calibration procedure.


CONNECTOR PINOUT, DB-37 MALE

         _____________________________________

P7

COMMON	19  	O

                          	O	37	PORT A- PA0

+5V	18	O

                          	O	36	PORT A- PA1

COMMON	17   	O

                          	O	35	PORT A- PA2

+12V	16   	O

                          	O	34	PORT A- PA3

COMMON	15   	O

                          	O	33	PORT A- PA4

-12V	14	O

                          	O	32	PORT A- PA5

COMMON	13   	O

                          	O	31	PORT A- PA6

-5V	12	O

                          	O	30	PORT A- PA7

COMMON	11   	O

                          	O	29	PORT C- PC0

PORT B- PB0	10	O

                          	O	28	PORT C- PC1

PORT B- PB1	9  	O

                          	O	27	PORT C- PC2

PORT B- PB2	8 	O

O	26	PORT C- PC3

PORT B- PB3	7  	O

O	25	PORT C- PC4

PORT B- PB4	6	O

O	24	PORT C- PC5

PORT B- PB5	5	O

O	23	PORT C- PC6

PORT B- PB6	4	O

O	22	PORT C- PC7

PORT B- PB7	3	O

O	21	GROUND

INT. ENABLE           	2	O

O	20	+5V

INT. INPUT	1	O


   CONNECTOR PINOUT, REMOTE CONNECTOR

P6

START	1	O

ABORT	2	O

RUN	3	O

HOLD	4	O

N/C	5	O

GROUND	6	O

     Rev. 1/20/99	C:\DVC16CSC.rtf