16-Channel Universal Signal Conditioner for Voltage, RTD, and 4-20 mA Sensors

The SCB-2U-16FA-UNV Signal Conditioner is a programmable 16-channel universal signal conditioner for RTDs, silicon diodes, 4-20 mA output sensors, or any device with voltage output up to 60 V. The balanced differential input, low-noise gain stages, and programmable 4-pole filter remove aliases and maximize dynamic range for an attached A/D converter system. The dual-mode excitation supply provides either +24 V to power external pre- amplifiers, or a precision 100 μA constant current source to excite RTD’s or silicon diodes.

Programmable channel gain and optional 4-pole flat/ pulse low-pass filters provide clean, amplified “data acquisition ready” output signals. The AC-coupled amplifier stage provides programmable gain settings up to x1000 in a x1, 2, 5, 10 sequence with 0.1% accuracy. The standard unit includes a 4-pole dual-mode LP4FP low- pass filter available in two standard ranges, each with five programmable cutoff frequencies. The flat mode (LP4F) provides a maximally flat pass-band response; the pulse mode (LP4P) provides linear phase with optimized pulse response. A wideband mode (filter bypass) is also standard. Read more about PFI's flat/pulse mode filter technology.

Packaged in a 2U rack-mounted enclosure, the SCB- 2U-16FA front panel features 6-pin 38999 type circular connectors as inputs for each of the 16 channels. Test and Monitor BNCs allow for testing, monitoring, troubleshooting, and other diagnostics. Analog channel outputs are mass terminated to industry standard 37-pin D-shell connectors for easy connection to ADC inputs. An Ethernet connector with IP reset switch, a signal ground connector with ground source selection switch, and a power connector and power switch with status indicators are also located on the rear panel.

The settings on the SCB-2U-16FA are fully programmable via high-level, English-language readable remote commands or by a stand-alone spreadsheet style graphical user interface that runs on a Windows PC. Channel overload and current limit fault of the 24 V excitation supply are continuously monitored and indicated on the GUI panel or remote interface. Chassis temperature, volt- age, current, and loop resistance of RTD measurements are available on command without disruption of the RTD measurement.

Option F together with the SCB-7-TEST third-party test instruments and required adapters and cables adds Factory Acceptance Test (FAT) capability. The SCB FAT, initiated from the SCB GUI, is a fully automated, NIST trace- able series of tests that measure and report the unit’s performance against published specifications.

The SCB-2U-16FA is powered by 10.8 to 30 V DC and is supplied with a tension clamp power entry connector. An external AC-to-DC universal supply is available from Precision Filters.

SCB-2U-16FA-UNV Benefits

  • Compact 2U rack-mounted enclosure
  • Front-panel 6-pin circular input connectors
  • Standard D-shell output connectors for ADC input
  • GUI or remote command line control
  • 10 V, 60 V, and 4-20 mA input operating mode
  • Real-time channel monitoring for overload or current limit fault
  • Optional 4-pole flat/pulse filter
  • Optional Factory Acceptance Tests

The Model SCB-2U-16FA-UNV Salient Features

Number of Channels

  • 16 Channels

Input Connectors

  • 16 isolated 6-pin 38999 circular connectors at front panel

Input Characteristics

  • ± 10 V, ± 60 V, and 4-20 mA input modes  
  • Dual mode constant voltage (+ 24 VDC) and constant current (100 μA) sensor excitation supplies
  • DC coupled balanced differential input

Spreadsheet style graphical user interface for host PC control

  • High level command line interface
  • Settings are retained when the computer is disconnected

Amplifier and Filter

  • Gain Settings: 1, 2, 5, 10, 20, 50, 100, 200, 500 and x1000 with pre-filter overload detection. Gain is distributed around filter for 2X out-band reserve.
  • Filter:  Standard 4-pole, 4-zero flat/pulse low-pass filter w/ programmable bypass for wideband operation. Programmable for maximally flat (LP4F) or linear phase with optimized pulse response (LP4P)


  • DC coupled single-ended output

Output Connectors

  • Industry standard 37-pin D-shell connectors

Optional Test Subsystem

  • 3rd party test instrument package with supporting software for NIST-traceable calibration, self-test, and performance verification