cFP-CB-3 (National Instruments)

Isothermal Compact FieldPoint Connector Block (EOL)

General Description

Part Number

• Model: cFP-CB-3

• NI PN: 778618‑03, 188998A‑01

Key Specifications

• Interface: 37‑pin D‑Sub (to cFP module)

• Terminals: 18 isothermal screw terminals (vs 36 on cFP-CB-1)

• Wire Gauge: 16–26 AWG solid copper, 6 mm strip length

• Rated Voltage: 250 Vrms CAT II

• Rated Current:

  • V/C (power/common): 4 A

  • Signal terminals: 2 A

• CJC: High‑accuracy isothermal thermistor (optimized for TC)

• Isothermal Design: Minimizes terminal‑to‑terminal temperature gradients

• Strain Relief: Integrated bar + tie‑wrap anchors (high shock/vibration)

• Max Cable Diameter: 8 mm

• Mounting: Direct to cFP-BP‑x backplane

• Operating Temperature: ‑40 °C to +70 °C

• Certifications: CE, UL, CSA

• Weight: ~200 g

Main Features

• Isothermal Construction: Eliminates thermal gradients across terminals → more accurate CJC for thermocouples

• 18 Dedicated TC Terminals: Clean, low‑drift connections for millivolt‑level TC signals

• Built‑In Precision Thermistor: CJC matched to isothermal zone

• Heavy‑Duty Strain Relief: Secures cables in high‑shock/vibration environments

• Direct Backplane Mount: Hot‑swap compatible, same footprint as cFP-CB‑1

Applications

• Thermocouple Measurement (Primary): Best for cFP-TC-120 / cFP-TC-125 in process, industrial, and environmental monitoring

• Low‑level mV signal conditioning where temperature drift must be minimized

• High‑accuracy temperature control loops (furnaces, reactors, HVAC)

• Legacy Compact FieldPoint TC system maintenance

cFP-CB-1 vs cFP-CB-3 (Quick)

• cFP-CB-1: 36 terminals, general‑purpose, works for AI/AO/DI/DO; basic CJC

• cFP-CB-3: 18 isothermal terminals, TC‑optimized, superior CJC accuracy