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| Specifications for the ACT Series of |
| Mechanical Loading Actuators |
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| Revised: Oct. 30, 2000 |
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| Introduction |
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| The ACT series of computer controlled actuators are very similar in design to hydraulic actuators except the piston rod is replaced by an internal ball screw which is driven by a DC servo motor. The actuators may be mounted in any position for performing tension and compression testing on structures or load frames. The ACT series actuators are available in many different load capacities and stroke lengths over the range from 5 kN ( 1,100 lb) up to 50 kN (11,000 lb). The actuator design consists of a single ball screw driven mechanical loading actuator which protrudes from the mounting plate end of the actuator. The screw is driven by a DC servo electric motor operating in closed loop control for accurate loading control. The easy to use Model TC-100 software is used for testing in tension and compression loading. The rugged design features of the ACT Series makes these systems suitable for a wide variety of applications in both quality control and Research and Development testing of products and components. Software packages are also available for performing creep tests and low cyclic rate fatigue testing. In addition, modifications to the software packages and the standard machine designs are available for special applications. |
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| Figure 1 shows the major part locations and dimensions of two of the ACT series of actuators. Other sizes are available on request. |
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| Mechanical Specifications |
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| 1. Test Speeds and Ranges (at rated capacity) |
| Standard speeds: 0.005 - 100 mm / min (0.0002 - 4.0 in / min) |
| Other speeds available on request. |
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| 2. 350 mm (14 in) stroke length. Other stroke lengths on request. |
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| 3. The loading mechanism consists of a ball screw type actuator rod which |
| protrudes from the mounting platen end of the actuator. It is driven by a |
| DC servo motor mechanically coupled to a worm drive system. |
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| 4. The DC servo motor has a shaft mounted encoder. The encoder is used for |
| both actuator rod position calculation and speed control. Internally mounted |
| limit switches are used to prevent overshoot of the actuator rod at both |
| maximum and minimum stroke length positions. |
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| 5. Standard Load Cell: Full Wheatstone bridge type rated for testing |
| system capacity in tension and compression. |
| Lower capacity load cells are also available. |
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| 6. Power Requirements: 110 - 120 VAC, 60 Hz, 1 phase or |
| 220 - 240 VAC, 50 Hz, 1 phase |
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| Specifications are Subject to Change without Notice |
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| Motor Control System |
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| The motor control system requires an IBM compatible 486DX or Pentium type PC system with a color VGA monitor, hard drive, 3.5 inch 1.44 MB high density floppy drive, and minimum 1 MB RAM. Two unused ISA type expansion slots on the mother board are required for the control and data acquisition cards. For report printouts, a Hewlett Packard Series 600 Deskjet printer (ie. Model 692C, 695C, 697C, etc.) or Panasonic 24 pin dot matrix printer (ie. Model KX-P2023) is required. A 386DX type IBM compatible PC may also be used but data acquisition speed will be considerably reduced. The ATM software requires Microsoft DOS Version 5.0 or higher, Windows95, or Windows98 as the operating system. The ATM software will not function under WindowsNT or Windows2000. The software packages run under DOS and should be run under the Real DOS mode if using Windows95 or Windows98. The motor control hardware consists of two ISA type expansion boards and an electrical control box containing the motor control electronics and combined DC and AC conditioners system. The two ISA expansion boards consists of a 12 bits resolution A/D / D/A / I/0 board and a servo motor controller board. The servo motor controller board uses the encoder feedback signal and software commands to produce the motor control system command signal. The motor control system consists of a DC power supply for powering the DC servo motor and a servo amplifier for amplification of the servo controller board command signal. |
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| Two selector switches mounted on the front panel of the electrical control box are used for Manual Control positioning of the actuator. The actuator is moved Up and Down using a spring return switch. A second switch designated Fast/Slow is used to select the speed of the manual positioning motion. |
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| A circuit board containing two DC and two AC conditioners is located inside the electrical control box. The input connections from the rear panel and front mounted Manual Control switches are made to this board. The DC conditioners can be used for excitation and amplification of the ATM line of load cells and extensometers. The AC conditioners are used for amplification and demodulation of LVDT type devices. Provision is made on the rear panel for monitoring the conditioner outputs using BNC type connectors. Also, 15 turn potentiometers are accessible through the electrical control box right side panel for adjustment of the Gain and Input and Output Offset adjust (ie. Zero) for each conditioner output. The DC conditioners also have a push button Cal Chk switch for a quick check of correct transducer calibration. For a typical setup, the DC conditioner 1 is used with the standard capacity load cell. DC conditioner 2 is available for use with a lower capacity load cell or a DC type extensometer. |
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| Data Acquisition System |
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| Computer data acquisition is performed using a 12 bit A/D D/A I/0 board. This board mounts in one of the PC bus ISA type card slots. There is provision on the board for changing the board address location by means of a DIP switch. If this is required, a data file in the software must be modified for the new address location. The female DB subminiature type 25 contact connector on the rear of the 12 bit A/D D/A I/O board connects using a "Straight Thru" style cable directly to the AC/DC conditioner board mounted in the electrical control box. The D/A A/D I/O board supplies the +15 VDC and +5 VDC power required for operation of the AC/DC conditioner circuit board. The A/D input and D/A output ranges are set at -/+10 VDC. Two D/A outputs and an I/0 signal are available via BNC connections. These are not used in the standard ATM software packages but are intended for use in customized versions of the ATM software and for future applications. The amplified outputs of the AC/DC conditioner board are connected to the data acquisition card through the main cable. |
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| Computer Software Descrilption |
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| The Model TC-100 Tension/Compression software package is included with the |
| purchase of an ACT series actuator system. The software features a user friendly environment to perform such tasks as selecting the testing speed. A Demonstration Version of the software is available. Please contact ATM for information on how to obtain a copy. A brief description of the software is given as follows. |
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| The Main Screen of the TC-100 software shown in Figure 2 presents the Operator with the current data set plotted on an X-Y graph. When the software is started, the data set plotted on the X-Y graph and the test parameters displayed are those which were current at the previous software shutdown. This data set and test parameters are stored in the TESTBAK.000 file. The present Tensile/Compressive and Yield Strengths for the data set are displayed in the Present Data box in the upper left hand screen. (Note: The Yield Strength will only be shown if the test was performed with an extensometer which is required to calculate the strain in the specimen.) Below this box, the Limits Box will show if any load, stroke, strain, or time limits are being exceeded. The Current Test box shows test setup parameters such as testing speed, data sampling rate, specimen type, specimen dimensions, etc. Three additional screens of information for the Current Test box are accessible in the Main Screen configuration using the <UP> arrow key. The lower right portion of the screen displays the command descriptions of the keyboard function keys Fl to F8 and the <RIGHT> arrow key. The <RIGHT> arrow key is used to select a second set of command descriptions for the Fl to F8 keys. |
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| The design of the TC-100 software allows maximum flexibility for making changes to the testing configuration. The Operator can make changes to the display screen with the F7 Change Setup key with minimum disruption of the background display. |
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| Up to 300 data sets can be stored at a time in the directory which contains the TC-100 operating software. The TESTS.NAM file contains a listing of the data sets that are available for display. The data set generated during a test can be stored to the hard drive with a filename which the Operator enters or is automatically generated by the software. The resulting data files may be reloaded or erased from within the program. |
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| Performing replicate tests is easily accomplished with a minimum of Operator inputs. The system features the software selectable F2 Zero Offsets command for removing any offset load or other non zero transducer signal resulting from changes in the test grips or test setup. An Automatic Return feature which is activated at test completion may be chosen which automatically or after an Operator key input returns the actuator rod to its position at the start of the test. |
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| During a test, the results are displayed in Real-Time to the monitor on an X-Y plot. The current value of the individual point being displayed is updated during the test in the Present Data box. The test can be stopped at a preselected end point determined by such parameters as maximum time limit, load limit, after sample breakage, % load drop after maximum value, or by pressing the <Esc> key. In addition, the Operator may also Pause during the test after which time the test may be continued or aborted. The values corresponding to the test sample Tensile/Compressive Strength and Actuator Displacement at Fracture or % Elongation are calculated and displayed at test completion. If an extensometer is used for the X axis, the Yield Strength (Y.S.) will also be displayed. |
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| At test completion, the individual data points may be scrolled with the PS Trace Test Curve function using the <LEFT> and <RIGHT> arrow keys. Also, the data may be replotted by changing the axes scales or with different Engineering Units and the resultant data stored under a different filename. The PS Data Functions key may be used to display multiple data sets for comparison, storing data sets, or erasing stored data sets. |
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| For simplifying multiple test setup requirements, up to 100 test setups may be stored using the F6 Test Setups key. These are listed in the SETUPS.NAM file. When a test setup is loaded, the displayed data set is reconfigured to the new test setup X and Y axes and Engineering Units. |
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| Other software features include the capability of printing one page summary test reports on a Hewlett Packard 600 or 800 Series DeskJet printer (ie. Model 692C, 695C, 697C, 832C, etc.) or a Panasonic 24 pin dot matrix printer (ie. Model KX- P2023). Figure 3 shows a sample test report. The Operator may change the axes scales of the graph and view the results on the monitor before printout. The test report contains information such as the material type, date and time of test, Test Operator identification, number of test points, and fracture values. The test report can also be configured to exclude the X-Y plot of the test data. |
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| Other software packages are available for performing creep tests and low cyclic rate fatigue tests. In addition, existing software packages can be customized for unique testing requirements which can not be performed with the standard software. Please contact Adelaide Testing Machines if you have specific testing requirements which may not behandled by our standard software packages. |
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| Optional Features |
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| Additional features may be supplied with the ACT series of actuators to enhance their capabilities. Some of these are listed as follows: |
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| a) Bellows Covers on Actuator (Option ACTxxxxx.BSC) |
| For dusty environments, ATM can supply the ACT series actuators with a bellows cover over the actuator rod to prevent dust from coating the linear bearing guiding the actuator rod through the platen. This option is a factory installed modification and should be ordered with the system. |
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| In addition to the listed options, ATM can provide additional modifications to the standard actuators to accommodate specific requirements. Some of these options include longer actuator travel length, very low speed range for ultra low speed control applications, and others. Please contact us with your additional requirements. |
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| Accessories |
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| A wide range of accessories such as test grips and fixtures can be provided by ATM to allow testing of many different sample types or customer products. The following lists some of the items that are available from ATM. |
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| a) Extensometers |
| ATM can provide linear, diametral, biaxial, non contact laser type and elevated extensometry equipment for most applications. They are available in a wide range of deflections and temperature ranges for use with the ATM line of software and test equipment. Please contact ATM for your specific requirements for extensometry equipment. |
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| b) Material Testing Grips |
| An extensive line of material testing grips such as wedge loading tensile grips, clevis grips, compression plates, 3 and 4 point bending fixtures, and others can be provided. Special high temperature grips for ceramics testing are also available. ATM can also custom design test grips or test fixtures to test component parts. Please contact ATM for all your test fixture requirements. |
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| c) High Temperature Test Ovens |
| ATM can supply split tubular or box type testing ovens in a range of temperatures up to 1,200 F and a very high temperature line for materials testing up to a maximum temperature capability of 2,800 F. These models may be supplied with mounting structures to mount them directly to customer specified equipment on which the ACT series actuator is to be used. |
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| d) Environmental Chambers |
| Low temperature environmental chambers with temperature and/or humidity control are also available. These chambers are of mainly stainless steel construction and are designed with the same accessibility as the test ovens. These chambers may be supplied with mounting structures to mount them directly to customer specified equipment on which the ACT series actuator is to be used. |
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| e) Customized Electronics Packages |
| The ATM line of DC and AC conditioners may also be supplied in rack mounted versions for excitation and amplification of multiple source Wheatstone bridge type device input signals. Other manufacturer's load cells and extensometers may also be adapted for use with ATM equipment. Please contact ATM for further information. |
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