User ManualTable of ContentsNI 2501/2503 User Manual1Support2Internet Support2Bulletin Board Support2Fax-on-Demand Support2Telephone Support (USA)2International Offices2National Instruments Corporate Headquarters2Important Information3Warranty3Copyright3Trademarks3WARNING REGARDING MEDICAL AND CLINICAL USE OF NATIONAL INSTRUMENTS PRODUCTS3Compliance4Conventions5Contents6Chapter 1 Routing Signals with Your NI 2501/25038About the NI2501/25038Analog Bus9Triggers9Cold-Junction Sensor Channel10NI2501 Amplifier10Connecting Signals11Front Connector11Contact Protection17Terminal Blocks17Software Choices17NISWITCH Driver Software17National Instruments Application Software18Third Party Software18Chapter 2 NI 2501/2503 Operation19Functional Overview19Multiplexer22Two-Wire Mode22One-Wire Mode22Four-Wire Mode23Matrix Mode23Switch Control Circuitry23Random Scanning23PXI Interface24Triggers24External Trigger Input24Scanner Advanced25Modes25Initiating Scanning26Multicard Triggering26Appendix A Specifications27NI250127Input Characteristics27Transfer Characteristics28Dynamic Characteristics28PXI Bus Interface29PXI Trigger Bus29Power Requirement29Physical29Environment30Shock and Vibration30Certifications and Compliances CE Mark Compliance30NI250331Input Characteristics31Transfer Characteristics31Dynamic Characteristics32PXI Bus Interface32PXI Trigger Bus32Power Requirement32Physical33Environment33Shock and Vibration33Certifications and Compliances CE Mark Compliance33Appendix B Accessories34Appendix C Customizing Your Card35CurrentLoop Receivers35Appendix D Architecture Drawings37Appendix E Common Questions40Appendix F Customer Communication42Electronic Services42Telephone and Fax Support43Technical Support Form44NI2501/2503 Hardware and Software ConfigurationForm45National Instruments Products45Other Products45Documentation Comment Form47Glossary48A48B48C49D49E50F50H50I50M50N51P51R51S51T52V52W53Index54A54B54C54D54E54F54G55I55L55M55N55O55P56Q56R56S56T57V57Figures7Figure 1-1. Front Connector Pinout Assignments for Two-Wire Mode12Figure 1-2. Front Connector Pinout Assignments for One-Wire Mode13Figure 1-3. Front Connector Pinout Assignments for Four-Wire Mode14Figure 1-4. Front Connector Pinout Assignments to Create a 6 x 4 Matrix15Figure 2-1. NI 2501 Module Block Diagram20Figure 2-2. NI 2503 Module Block Diagram21Figure C-1. Bent and Trimmed Resistor36Figure D-1. NI 2501 Switch Architecture38Figure D-2. NI 2503 Switch Architecture39Tables7Table 1-1. Front Connector Signal Description16Size: 397 KBPages: 57Language: EnglishOpen manual