National Instruments SCB-68 User Manual Download

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Contents

National Instruments Corporation

SCB-68 Shielded Connector Block User Manual

Selecting a Resistor .........................................................................................5-17
Adding Components........................................................................................5-18

Single-Ended Inputs ..........................................................................5-18
Differential Inputs .............................................................................5-18

Attenuating Voltage .......................................................................................................5-18

Theory of Operation ........................................................................................5-19
Selecting Components .....................................................................................5-20

Accuracy Considerations ..................................................................5-20

Adding Components........................................................................................5-20

Single-Ended Input Attenuators........................................................5-20
Differential Input Attenuators ...........................................................5-21
Analog Output and Digital Input Attenuators...................................5-22

Special Considerations for Analog Input ........................................................5-22
Special Considerations for Analog Output......................................................5-23
Special Considerations for Digital Inputs........................................................5-24

Appendix A
Specifications

Appendix B
Quick Reference Labels

Appendix C
Fuse and Power

Appendix D
SCB-68 Circuit Diagrams

Appendix E
Soldering and Desoldering on the SCB-68

Appendix F
Technical Support and Professional Services

Glossary

Index

Summary of Contents for SCB-68

Page 1: ...DAQ SCB 68 68 Pin Shielded Connector Block User Manual SCB 68 Shielded Connector Block User Manual December 2002 Edition Part Number 320745B 01...

Page 2: ...4 24 24 Germany 089 741 31 30 Greece 01 42 96 427 Hong Kong 2645 3186 India 91 80 4190000 Israel 03 6393737 Italy 02 413091 Japan 03 5472 2970 Korea 02 3451 3400 Malaysia 603 9596711 Mexico 001 800 01...

Page 3: ...nstallation operation or maintenance instructions owner s modification of the product owner s abuse misuse or negligent acts and power failure or surges fire flood accident actions of third parties or...

Page 4: ...ruments could void the user s authority to operate the equipment under the FCC Rules Class A Federal Communications Commission This equipment has been tested and found to comply with the limits for a...

Page 5: ...ncludes a DoC for most every hardware product except for those bought for OEMs if also available from an original manufacturer that also markets in the EU or where compliance is not required as for el...

Page 6: ...Chapter 2 Parts Locator and Wiring Guide Switch Configuration 2 3 Chapter 3 Connecting Signals Connecting Analog Input Signals 3 1 Input Modes 3 1 Nonreferenced or Floating Signal Sources 3 3 Differe...

Page 7: ...Conditioning Analog Output Channels 5 3 Conditioning PFI0 TRIG1 5 4 Accuracy and Resolution Considerations 5 5 Open Thermocouple Detection 5 5 Differential Open Thermocouple Detection 5 6 Single Ended...

Page 8: ...ts 5 20 Single Ended Input Attenuators 5 20 Differential Input Attenuators 5 21 Analog Output and Digital Input Attenuators 5 22 Special Considerations for Analog Input 5 22 Special Considerations for...

Page 9: ...n This icon denotes a caution which advises you of precautions to take to avoid injury data loss or a system crash When this symbol is marked on the device refer to the Safety Information of Chapter 1...

Page 10: ...lded Connector Block User Manual xii ni com NI Documentation For more information about using the SCB 68 with DAQ devices refer to the following resources DAQ device user manuals at ni com manuals NI...

Page 11: ...e attenuation The open component pads allow signal conditioning to be easily added to the analog input AI signals and to the DAC0OUT DAC1OUT and PFI0 TRIG1 signals of a 68 pin or 100 pin DAQ device Wh...

Page 12: ...to Appendix B Quick Reference Labels for the switch configurations and screw terminal pinouts that are included on each quick reference label Table 1 1 shows cabling options and features for DAQ devi...

Page 13: ...y RC filtering NI 671X 673X for PCI PXI CompactPCI SH68 68 EP SH68 68 R1 EP R6868 Direct feedthrough only RC filtering NI 6715 for PCMCIA DAQCard 6715 SHC68 68 EP RC6868 Direct feedthrough only RC fil...

Page 14: ...68 68 Not recommended for use with the SCB 68 To maximize the available features NI recommends using this DAQ device with the CB 68T TBX 68 or TBX 68T terminal blocks NI 4351 for PCI PXI CompactPCI SH...

Page 15: ...eference label provided with the DAQ device Using 68 Pin Cables Table 1 1 lists the 68 pin cable assemblies that can connect the SCB 68 to a 68 pin DAQ device Each end of these 68 pin cables has a 68...

Page 16: ...SCB 68 connector blocks to a 100 pin DAQ device The SH1006868 is Y shaped with a 100 pin male connector on one end and two 68 pin female connectors on the opposite end The DAQ device connects to the...

Page 17: ...Each 68 pin end of the SH1006868 cable has a label that indicates which I O connector pinout is associated with that 68 pin I O connector Figure 1 4 shows the pin assignments for the I O connector on...

Page 18: ...DIO2 DGND DIO5 DIO0 DGND AOGND2 AOGND2 AIGND ACH7 ACH14 AIGND ACH5 ACH12 AISENSE ACH11 AIGND ACH2 ACH9 AIGND ACH0 1 35 2 36 3 37 4 38 5 39 6 40 7 41 8 42 9 43 10 44 11 45 12 46 13 47 14 48 15 49 16 5...

Page 19: ...NC NC NC NC NC NC NC ACH55 ACH54 ACH61 ACH52 ACH51 ACH58 ACH49 ACH48 ACH47 ACH38 ACH37 ACH44 AIGND ACH35 ACH34 ACH41 ACH32 ACH23 ACH30 ACH21 ACH20 ACH27 ACH18 ACH17 ACH24 NC NC NC NC NC NC NC NC NC A...

Page 20: ...8 E Series I O Connector Pinout Extended Digital NC NC NC NC NC NC NC NC NC 5V PA0 GND PA2 PA3 GND PA5 PA6 GND PB0 PB1 GND GND PB4 PB5 GND PB7 PC0 GND PC2 PC3 GND PC5 PC6 GND NC NC NC NC NC NC NC NC N...

Page 21: ...built into the SCB 68 if the device is damaged in any way If the SCB 68 is damaged return it to NI for repair Do not substitute parts or modify the SCB 68 except as described in this document Use the...

Page 22: ...secondary of an isolation transformer Examples of Installation Category I are measurements on circuits not derived from MAINS and specially protected internal MAINS derived circuits Installation Cate...

Page 23: ...ry motors with a permanent connection to the building fixed installation Installation Category IV is for measurements performed at the source of the low voltage 1 000 V installation Examples of Instal...

Page 24: ...68 dangerous voltages may exist even when the equipment is powered off To avoid dangerous electrical shock do not perform procedures involving cover or shield removal unless you are qualified to do so...

Page 25: ...SCB 68 COPYRIGHT 1993 68 J1 34 12 46 13 47 14 48 15 49 16 50 17 51 18 52 19 53 20 54 21 55 22 56 1 35 2 36 3 37 4 38 5 39 6 40 7 41 8 42 9 43 10 44 11 45 67 33 66 32 65 31 64 30 63 29 62 28 61 27 60...

Page 26: ...lso remove the top strain relief bar if you are connecting many signals Add insulation or padding if necessary 5 Connect the wires to the screw terminals by stripping off 0 25 in of the insulation ins...

Page 27: ...temperature sensor disabled and accessory power disabled Analog input analog output digital I O and timing I O Temperature sensor disabled and accessory power enabled2 Note This configuration is the f...

Page 28: ...tting is not recommended for use with the NI 653X NI 670X or NI 660X Refer to the device user manual at ni com manuals to determine if the device supplies 5 V to I O pin 8 2 Only applies to the signal...

Page 29: ...RSE input mode is used for floating signal sources In this case the DAQ device provides the reference ground point for the external signal NRSE input mode is used for ground referenced signal sources...

Page 30: ...ignal Source Examples Ungrounded thermocouples Signal conditioning with Isolated outputs Battery devices Examples Plug in instruments with nonisolated outputs Input Differential DIFF Single Ended Grou...

Page 31: ...connected to AIGND on one input if they are DC coupled or on both inputs if sources are AC coupled You can install bias resistors in positions B and D of the SCB 68 as shown in Figure 5 1 Analog Input...

Page 32: ...round referenced signal sources connected to the SCB 68 need no special components You can leave the inputs of the SCB 68 in the factory configuration with the jumpers in the two series positions F an...

Page 33: ...tion is one in which the DAQ device AI signal has its own reference signal or signal return path These connections are available when the selected channel is configured in DIFF input mode The input si...

Page 34: ...Ground Referenced Signals With this connection type the instrumentation amplifier rejects both the common mode noise in the signal and the ground potential difference between the signal source and th...

Page 35: ...CH or ACH i 8 and AIGND This resistor provides a return path for the 200 pA bias current A value of 10 k to 100 k is usually sufficient If you do not use the resistor and the source is truly floating...

Page 36: ...e ground is tied to the negative input of the instrumentation amplifier You can use single ended input connections for input signals that meet the following conditions The input signal is high level g...

Page 37: ...instrumentation amplifier and the signal local ground reference is connected to the negative input of the instrumentation amplifier The ground point of the signal should therefore be connected to AIS...

Page 38: ...e voltage output channel for AO channel 0 DAC1OUT is the voltage output channel for AO channel 1 EXTREF is the external reference input for both AO channels AOGND is the ground reference signal for bo...

Page 39: ...eference You can program all lines individually to be inputs or outputs Note For more information refer to the device user manual at ni com manuals for detailed signal description and connection infor...

Page 40: ...ble function input PFI lines 0 9 These PFI lines are bidirectional as outputs they are not programmable and reflect the state of many DAQ waveform generation and general purpose timing signals The rem...

Page 41: ...take proper care when running signal wires between signal sources and the device The following recommendations apply mainly to AI signal routing to the device although they also apply to signal routin...

Page 42: ...or all signal connections to the DAQ device Separate DAQ device signal lines from high current or high voltage lines These lines can induce currents in or voltages on the DAQ device signal lines if th...

Page 43: ...etters that indicate their composition according to the American National Standards Institute ANSI conventions To determine the type of thermocouple that you are using refer to Table 4 1 For more info...

Page 44: ...CJC with the SCB 68 is accurate only if the temperature sensor reading is close to the actual temperature of the screw terminals When you read thermocouple measurements keep the SCB 68 away from draf...

Page 45: ...ch Configuration Special Considerations To connect a high value resistor between the positive input and 5V refer to the Accuracy and Resolution Considerations section of Chapter 5 Adding Components fo...

Page 46: ...on Lowpass filtering Measuring 4 20 mA current Voltage attenuation Analog output Lowpass smoothing filter Voltage attenuation Digital input Lowpass digital filter Voltage attenuation In addition to th...

Page 47: ...an be used as either a differential channel pair or as two single ended channels Table 5 1 correlates the component labels of the SCB 68 to component locations A G for differential channels 0 7 In the...

Page 48: ...igure 5 3 shows the AO channel configuration for DAC0OUT Figure 5 2 Analog Output Channel Configuration Diagram ACH4 R30 RC20 RC21 R31 RC8 R12 R13 ACH5 R32 RC22 RC23 R33 RC9 R14 R15 ACH6 R34 RC24 RC25...

Page 49: ...OUT Conditioning PFI0 TRIG1 Figure 5 4 illustrates the digital input channel configuration and Figure 5 5 shows the digital input channel configuration for PFI0 TRIG1 Figure 5 4 Digital Input Channel...

Page 50: ...0 when you measure a signal between 10 to 10 V Gain which is determined by the input limits of the application is a value you apply to amplify or attenuate the signal Gain is expressed in decibels and...

Page 51: ...y keeping the SCB 68 away from drafts heaters and warm equipment Thermocouple output voltages are nonlinear with respect to temperature Conversion of the voltage output to temperature using either loo...

Page 52: ...nents for lowpass filtering Theory of Operation Lowpass filters highly or completely attenuate signals with frequencies above the cut off frequency or high frequency stopband signals but lowpass filte...

Page 53: ...having a gain of absolute zero for frequencies greater than fc the real filter has a transition region between the passband and the stopband a ripple in the passband and a stopband with a finite atte...

Page 54: ...nging in the signal as the higher frequency components of the signal are delayed Figure 5 8 Square Wave Input Signal Figures 5 9 and 5 10 show the difference in response to a square wave between an id...

Page 55: ...igure 5 11 shows the transfer function of a simple series circuit consisting of a resistor R and capacitor C when the voltage across R is assumed to be the output voltage Vm Figure 5 11 Transfer Funct...

Page 56: ...llowing characteristics Low wattage of approximately 1 8 W Precision of at least 5 Temperature stability Tolerance of 5 AXL package suggested Carbon or metal film suggested Choose a capacitor that has...

Page 57: ...g Figure 5 12 SCB 68 Circuit Diagram for a Single Ended Lowpass Filter Differential Lowpass Filter To build a differential lowpass filter refer to Figure 5 13 Add the resistor to position E and the ca...

Page 58: ...or value and choose a commercial capacitor value that satisfies the following relationship 5 6 Antialiasing Filtering Aliasing causes high frequency signal components to appear as a low frequency sign...

Page 59: ...implemented at the SCB 68 terminal block NI PCI PXI 61XX not including the NI PCI 6110 6111 NI PCI 445X NI PCI 455X Special Consideration for Analog Input Channels Filtering increases the settling tim...

Page 60: ...eration for Digital Trigger Input Signals Lowpass filters can function as debouncing filters to smooth noise on digital trigger input signals thus enabling the trigger detection circuitry of the DAQ d...

Page 61: ...Measuring a 4 to 20 mA Current Since DAQ devices cannot directly measure current this section describes how to add components for measuring current when transistors output a current value ranging bet...

Page 62: ...minator and Vin is the input voltage into the DAQ device 5 8 Selecting a Resistor For best results when measuring current you should choose a resistor that has the following characteristics Low wattag...

Page 63: ...ively Calculate the current according to Equation 5 9 or 5 10 5 9 5 10 Differential Inputs To build a one resistor circuit that measures current at the differential inputs of the SCB 68 add the resist...

Page 64: ...quation 5 13 to determine the overall gain of a voltage divider circuit 5 13 The accuracy of Equation 5 13 depends on the tolerances of the resistors that you use Caution The SCB 68 is not designed fo...

Page 65: ...ting voltage you should choose a resistor that has the following characteristics Low wattage of approximately 1 8 W Precision of at least 5 Temperature stable Tolerance of 5 AXL package suggested Carb...

Page 66: ...ions 5 14 or 5 15 to calculate the gain of the circuit 5 14 5 15 Differential Input Attenuators To build a three resistor circuit for attenuating voltages at the differential inputs of the SCB 68 refe...

Page 67: ...or Digital Input Attenuation Use positions R1 and RC1 for TRIG1 and determine the gain according to Equation 5 17 5 17 Use positions R2 and RC2 for DAC1OUT and determine the gain according to Equation...

Page 68: ...5 19 for AO the output impedance changes Thus you must choose the values for R1 and R2 so that the final output impedance value is as low as possible Refer to Appendix A Specifications in the device u...

Page 69: ...f you use the Vin voltage of Figure 5 20 to feed TTL signals you must calculate Vin so that the voltage drop on R2 does not exceed 5 V Caution A voltage drop exceeding 5 V on R2 can damage the interna...

Page 70: ...at 5 VDC 5 Typical 1 mA with no signal conditioning installed Maximum 800 mA from host computer Note The power specifications pertain to the power supply of the host computer when using internal power...

Page 71: ...w terminals 68 Wire gauge 26 AWG Resistor sockets 0 032 to 0 038 in in diameter Maximum Working Voltage Maximum working voltage refers to the signal voltage plus the common mode voltage Channel to ear...

Page 72: ...C Part 15 Class A Compliant Note For EMC compliance you must operate this device with shielded cabling CE Compliance This product meets the essential requirements of applicable European Directives as...

Page 73: ...nts Corporation B 1 SCB 68 Shielded Connector Block User Manual B Quick Reference Labels This appendix shows the pinouts that appear on the quick reference labels for the DAQ devices that are compatib...

Page 74: ...SORY POWER ON ON SINGLE ENDED CH 0 S4 FACTORY DEFAULT SETTING ACCESSORY POWER ON TEMP SENSOR DISABLED S5 S5 DGND 13 ACH9 66 AIGND ACH3 ACH2 ACH10 AIGND AISENSE AIGND ACH11 S3 62 29 30 63 S1 S2 64 31 3...

Page 75: ...VCH7 ICH23 AGND6 AGND22 ICH22 AGND7 AGND23 VCH6 67 33 34 68 ICH30 AGND15 AGND31 45 11 DGND DGND DIO6 AGND DGND ICH31 44 10 DIO7 43 9 41 42 8 DIO5 40 7 2 DIO0 DIO1 DIO3 RFU DIO4 DGND DGND 6 39 5 38 DI...

Page 76: ...GND AOGND DAC6OUT AOGND AOGND NC DAC5OUT AOGND AOGND DAC4OUT AOGND AOGND DAC3OUT AOGND AOGND DAC2OUT AOGND AOGND NC AOGND AOGND NC DAC7OUT 62 29 30 63 64 31 32 65 50 17 DIO1 DGND 49 16 DIO2 DIO6 15 48...

Page 77: ...09B 01 S4 FACTORY DEFAULT SETTING ACCESSORY POWER ON TEMP SENSOR DISABLED S5 DGND 13 ACH1 66 ACH1GND ACH3 ACH2 ACH2 ACH2GND ACH3GND ACH3 62 29 30 63 64 31 32 65 50 17 DIO1 DGND 49 16 DIO2 DIO6 15 48 D...

Page 78: ...58 24 57 23 PIN 12 46 13 47 14 48 15 49 16 50 17 51 18 52 19 53 20 54 21 55 22 56 SIGNAL 5V RG PFI_39 SOURCE_0 GND PFI_38 GATE_0 RESERVED RESERVED RESERVED PFI_36 OUT_0 GND PFI_33 UP_DOWN_1 PFI_37 UP...

Page 79: ...GND DIOD1 DIOD0 GND DIOC7 DIOC6 GND DIOC5 DIOC4 GND DIOC3 DIOC2 GND DIOC1 DIOC0 PIN 68 34 67 33 66 32 65 31 64 30 63 29 62 28 61 27 60 26 59 25 58 24 57 23 SIGNAL DIOA3 GND DIOA4 DIOA5 GND DIOA6 DIOA...

Page 80: ...DGND DIO7 DIO8 DIO9 DIO10 DIO11 PIN 1 35 2 36 3 37 4 38 5 39 6 40 7 41 8 42 9 43 10 44 11 45 MIO DIO DIO12 DIO13 DIO14 DIO15 AOGND7 AO7 AOGND6 AO6 AOGND5 AO5 AOGND4 AO4 AOGND3 AO3 AOGND2 AO2 AOGND0 AO...

Page 81: ...replacing any fuses check for short circuits from power to ground A 470 series resistor R21 filters the 5 V power on the SCB 68 As the filtered 5 V is loaded the voltage decreases Pad R20 is in paral...

Page 82: ...strations of circuit diagrams for the SCB 68 Figure D 1 5 V Power Supply 5V I O Pin 8 5V Screw Terminal ACC Not Powered NC C2 10 F XF1 Clip 800 mA 5x20 mm S1 ACC Powered C1 0 1 F R20 Optional R21 C6 1...

Page 83: ...al Trigger Circuitry ACH0 I O Pin 68 S5 CJC Not Used CJC Used R38 Q1 5V C3 0 1 F C5 1 F R23 5V R5 ACH8 Screw Terminal S4 ACH8 I O Pin 34 RSE CJC or Non MIO DIFF CJC AI AI AI AIGND RC13 User Configurab...

Page 84: ...tion D 3 SCB 68 Shielded Connector Block User Manual Figure D 4 Analog Output Circuitry RC3 DAC0OUT I O Pin 22 R3 AOGND I O Pin 55 RC2 DAC1OUT I O Pin 21 R2 DAC1OUT Screw Terminal AOGND I O Pin 54 AOG...

Page 85: ...on the SCB 68 refer to Figure 2 1 SCB 68 Printed Circuit Diagram and to Figure E 1 and complete the following steps to remove the SCB 68 from its box Figure E 1 SCB 68 Parts Locator Diagram Note If th...

Page 86: ...ove the device mount screws and the 68 pin connector screws 6 Tilt the SCB 68 up and pull it out To reinstall the SCB 68 reverse the order of the steps The SCB 68 ships with wire jumpers in the F and...

Page 87: ...discussion forums a measurement glossary and so on Assisted Support Options Contact NI engineers and other measurement and automation professionals by visiting ni com ask Our online system helps you...

Page 88: ...t at ni com calibration If you searched ni com and could not find the answers you need contact your local office or NI corporate headquarters Phone numbers for our worldwide offices are listed at the...

Page 89: ...l Glossary Prefix Meanings Value p pico 10 12 n nano 10 9 micro 10 6 m milli 10 3 k kilo 103 M mega 106 G giga 109 Numbers Symbols degrees greater than less than or equal to greater than or equal to l...

Page 90: ...SE analog input sense signal AO analog output AOGND analog output ground signal ASIC Application Specific Integrated Circuit a proprietary semiconductor component designed and manufactured to perform...

Page 91: ...it that converts a digital number into a corresponding analog voltage or current DAC0OUT analog channel 0 output signal DAC1OUT analog channel 1 output signal DAQ data acquisition a system that uses t...

Page 92: ...s amplified often expressed in dB GATE gate signal GPCTR general purpose counter GPCTR0_GATE general purpose counter 0 gate signal GPCTR1_GATE general purpose counter 1 gate signal GPCTR0_OUT general...

Page 93: ...n I O N NC normally closed or not connected NI DAQ NI driver software for DAQ hardware noise an undesirable electrical signal noise comes from external sources such as the AC power line motors generat...

Page 94: ...tical maximum transfer rate of 132 MB s PFI Programmable Function Input PFI0 TRIG1 PFI0 trigger 1 PFI1 TRIG2 PFI1 trigger 2 PFI2 CONVERT PFI2 convert PFI3 GPCTR1_ SOURCE PFI3 general purpose counter 1...

Page 95: ...ressed in bits proportions or percent of full scale RH relative humidity rms root mean square RSE referenced single ended mode all measurements are made with respect to a common reference measurement...

Page 96: ...on of the temperature TRIG trigger signal TTL transistor transistor logic U unipolar a signal range that is always positive for example 0 to 10 V UPDATE update signal V V volts VDC volts direct curren...

Page 97: ...uple detection 5 5 to 5 7 analog input channels conditioning 5 2 to 5 3 component locations table 5 2 to 5 3 configuration diagram figure 5 2 input attenuators 5 22 to 5 23 lowpass filter consideratio...

Page 98: ...or pinout extended AI figure 1 9 SCB 68 E Series I O Connector pinout extended digital figure 1 10 SCB 68 E Series I O Connector pinout full figure 1 8 quick reference labels table 1 2 calibration cer...

Page 99: ...5 6 to 5 7 configuration quick reference label B 1 to B 8 quick reference label table 1 2 to 1 4 switch configuration 2 3 to 2 5 using Measurement Automation Explorer MAX 1 11 connecting signals 3 1...

Page 100: ...4 3 when to use 3 5 digital input channels input attenuators 5 22 5 24 lowpass filter considerations 5 12 PFIO TRIG1 configuration figure 5 4 digital I O DIO devices quick reference label table 1 3 d...

Page 101: ...filtering 5 13 to 5 14 noise filtering 5 13 Bode Plots for ideal and real filters figures 5 8 one pole lowpass RC filter 5 10 to 5 11 selecting components 5 11 special considerations analog input cha...

Page 102: ...rence label 1 2 to 1 4 B 1 to B 8 analog output AO devices table 1 3 digital I O DIO devices table 1 3 E series devices table 1 2 to 1 3 B 2 NI 653X devices table B 7 NI 660X devices table B 6 NI 670X...

Page 103: ...irement A 1 safety A 3 support services F 1 to F 2 switch settings configuration and affected signals table 2 3 to 2 5 temperature sensor configuration 4 2 to 4 3 system integration support F 1 T tech...

Page 104: ...Index SCB 68 Shielded Connector Block User Manual I 8 ni com special considerations analog input 5 22 to 5 23 analog output 5 23 digital inputs 5 24 theory of operation 5 19...

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