Product Description
National Instruments SCB-68 Shielded Connector Block – 68-Pin Screw Terminal I/O for DAQ Systems
This used National Instruments SCB-68 is a shielded I/O connector block designed to interface signals to plug-in data acquisition (DAQ) devices with 68-pin connectors . The SCB-68 provides a rugged, very low-noise signal termination solution when used with NI shielded DAQ cables .
The SCB-68 features 68 screw terminals that break out all I/O signals from the 68-pin male SCSI connector . It includes two general-purpose breadboard areas for building custom signal conditioning circuits and an onboard cold-junction compensation (CJC) sensor for thermocouple measurements . The terminal block is compatible with single- and dual-connector multifunction I/O devices including NI E, B, S, X, and M Series DAQ devices .
Condition Note: This unit is untested and sold as-is. No DAQ cable or mounting accessories are included unless specified. The unit is sold as “SCB-68” (original model) not “SCB-68A” .
Key Specifications
| Specification | Details |
|---|---|
| Manufacturer | National Instruments (NI / Emerson) |
| Model | SCB-68 |
| Part Number | 776844-01 |
| Type | Shielded I/O Connector Terminal Block |
| Back End Connection | 68-pin male SCSI connector (to DAQ device) |
| Front End Connection | 68 screw terminals (female) |
| Wire Gauge | 14–30 AWG |
| Screw Terminal Torque | 0.5–0.6 N·m (4.43–5.31 lb·in) |
| Power Consumption | 800 mA max at +5 VDC (±5%) from host computer |
| Fuse Rating | 1.10 A, 8 VDC SMT PTC (not user-replaceable) |
| Dimensions (W×D×H) | 5.8 × 5.8 × 1.2 inches (147 × 147 × 30 mm) |
| Weight | 1.41 lb (640 g) |
| Operating Temperature | 0 to 70°C |
| Storage Temperature | -20 to 70°C |
| Relative Humidity | 5 to 90% RH, noncondensing |
| Maximum Altitude | 2,000 m |
| Pollution Degree | 2 |
| NI List Price | $651.00 |
| Condition | Used – Untested |
Key Features & Benefits
| Feature | Benefit |
|---|---|
| Shielded Enclosure | Provides low-noise signal termination when used with NI shielded cables |
| 68 Screw Terminals | Easy, tool-based field wiring without special connectors |
| Cold-Junction Compensation Sensor | Enables accurate thermocouple measurements |
| Two Breadboard Areas | Allows custom signal conditioning circuit integration |
| 68-pin Male SCSI Connector | Connects directly to NI DAQ devices via standard SHC68 cable |
| DIN-Rail Mount Compatibility | Flexible installation options (SCB-68A variant adds this feature) |
| Resettable Fuse | Overcurrent protection on SCB-68A models |
DAQ Device Compatibility
The SCB-68 is compatible with NI multifunction I/O (MIO) DAQ devices with 68-pin connectors :
| Series | Compatible Models |
|---|---|
| E Series | PCI-6040E, PCI-6071E, PCI-6110/6111, etc. |
| M Series | PCI-6221, PCI-6229, PCI-6251, etc. |
| X Series | PCIe-6320, PCIe-6321, PCIe-6341, etc. |
| B/S/R Series | Most devices with 68-pin connectors |
Applications
-
Data Acquisition Systems: Signal breakout for NI DAQ devices in lab and industrial settings
-
Thermocouple Measurements: Cold-junction compensation enables accurate temperature readings
-
Prototype Circuit Development: Breadboard areas allow custom signal conditioning
-
Test & Measurement: Interface between sensors and PC-based DAQ systems
-
Education & Research: University laboratory data acquisition setups
-
Legacy System Support: Replacement or additional I/O termination for existing NI DAQ installations
The SCB-68 is particularly valuable as an educational tool, used in university engineering labs for hands-on signal conditioning and instrumentation courses .













