The NI SHC68-68-EP is a 1-meter shielded 68-conductor digital cable that connects National Instruments M Series and X Series DAQ devices to compatible accessories and expansion modules. It terminates with a 68-pin VHDCI connector on one end and a 68-pin female D-SUB connector on the other, enabling direct integration into multi-channel data acquisition systems. Internal construction features individually shielded analog input pairs and twisted digital pairs, with separate gauge provisions for power distribution and digital signaling. This configuration minimizes crosstalk and electromagnetic interference, making it suitable for precision measurement environments where signal integrity is critical.
Technical Specifications
Conductor Configuration
• 68 total conductors
• Analog input pairs: 30 AWG, individually shielded, 66 Ω differential impedance @ TDR, 23.0 pF/ft mutual capacitance, 0.83 ns/ft time delay
• Digital twisted pairs: 30 AWG, 107 Ω differential impedance @ TDR, 14.5 pF/ft mutual capacitance, 1.55 ns/ft time delay
• Digital single conductors: 30 AWG
• +5 V power lines: 26 AWG
• DC resistance for 30 AWG conductors: 0.099 Ω/ft @ 20 °C
• DC resistance for 26 AWG conductors: 0.040 Ω/ft @ 20 °C
Physical Dimensions
• Cable length: 1 meter
• Outer diameter: 0.540 in (13.7 mm)
• Minimum bend radius: 6.5 in (165 mm)
• Full shielding for enhanced noise reduction
– Key Features
• Matched impedance characteristics between analog and digital signal paths
• Individually shielded analog pairs reduce crosstalk in high-channel-count systems
• Differential pair construction for digital signals ensures timing accuracy
• Separate gauge sizing optimizes voltage drop and signal integrity across power and signal conductors
– Typical Applications
• Multi-channel analog signal acquisition with synchronized digital I/O
• Industrial automation and process monitoring systems
• Laboratory test setups requiring low-noise analog measurements
• Custom instrumentation harnesses for modular DAQ configurations
– Compatibility & Integration
Designed for National Instruments M Series and X Series DAQ devices featuring 68-pin VHDCI connectors. Compatible with DAQCards, selected S Series devices, and 68-pin D-SUB accessories. Operating temperature range is specified by the connected data acquisition product.
