OMB-DAQ55-Series

Supported Applications

The Omega OMB-DAQ Series (models -54, -55, and -56) comprises compact, USB-based multi-function data acquisition modules designed for portable data collection. These systems connect directly to a PC via Universal Serial Bus (USB), enabling measurement of voltage, thermocouple temperature, pulse, frequency, and digital I/O signals without requiring external power when connected to the host computer.

The series is engineered for applications where portability and ease of setup are required, allowing modules to be located up to 5 m (16.4') from the PC using standard USB cables. The system supports expansion via OMB-PDQ1 and OMB-PDQ2 modules, enabling configurations with up to 8000 channels across a single PC when utilizing USB hubs.

Operating Conditions & Performance

The series features a high-resolution 22-bit A/D converter for voltage and thermocouple measurements. Resolution is specified as 22 bits (±4V) under standard conditions, with frequency and duty-cycle measurements providing up to 7 digits of resolution depending on the scan rate.

• Accuracy: OMB-DAQ-55/56 models achieve 0.015% of reading +0.002% of range (exclusive of noise); OMB-DAQ-54 achieves 0.015% of reading +0.004% of range.
• Thermocouple Accuracy: J = ±1.1°C, K = ±1.2°C, T = ±1.1°C, E = ±1.0°C, R = ±2.5°C, S = ±2.6°C, B = ±3.3°C, N = ±1.5°C.
• Operating Temperature: 0 to 50°C (0 to 122°F).
• Humidity Rating: 95% RH (non-condensing).

Response time varies based on the selected rejection mode: 610 ms for 50/60 Hz Rejection or 12.5 ms in fast scan modes.

Voltage and Thermocouple Ranges

The modules support a wide array of input ranges configurable via software:

• DC Voltage (Differential): -20 to 20V, -10 to 10V, -5 to 5V, down to -31 to 31 mV.
• Thermocouple Types: J (-100 to 700°C), K (-200 to 1200°C), T (-100 to 400°C), E (-100 to 500°C), R (-400 to 1400°C), S (400 to 1400°C), B (700 to 1400°C), N (-100 to 700°C).

Configuration Options

The OMB-DAQ Series offers distinct channel capacities and I/O features across its three primary models, all housed in a compact enclosure measuring 92 W x 182 L x 45 mm H (3.6 x 7.1 x 1.6").

Model Configurations

• OMB-DAQ-54: A 10-channel system providing 5 Differential or 10 Single-ended analog inputs. This model does not include frequency measurement, digital I/O, or expansion capability.
• OMB-DAQ-55: Provides the same 10 analog channels (5 DE / 10 SE) plus 8 Digital I/O lines and 2 Frequency/Pulse input channels. It supports system expansion via OMB-PDQ modules.
• OMB-DAQ-56: Doubles the capacity of the -55 model, offering 20 analog inputs (10 DE / 20 SE), 16 Digital I/O lines, and 4 Frequency/Pulse input channels in the same physical package.

Expansion Options

The OMB-DAQ-55 and -56 models can be expanded using dedicated modules to increase channel counts:

• OMB-PDQ1 Expansion Module: Adds 20 analog channels (10 DE / 20 SE) and 16 Digital I/O lines.
• OMB-PDQ2 Expansion Module: Adds 40 analog channels (20 DE / 40 SE).

Cable options include the OMB-CA-179 series USB Type-A to USB Type-B cables in lengths of 1 m, 3 m, and 5 m. Spare terminal blocks are available as part number OMB-CN-153-12.

Key Product Differences

The primary distinction between the series members lies in their I/O density and feature set:

• Analog Capacity: The -54 is limited to 10 channels. The -56 provides double the analog input capacity of the -55 (20 vs. 10 inputs).
• Digital I/O and Frequency: Only the OMB-DAQ-55 and -56 models include Digital I/O (Open Collector Output) and frequency/pulse measurement capabilities; these features are absent in the OMB-DAQ-54.
• Expansion Support: The OMB-DAQ-54 cannot be expanded. Both the -55 and -56 support attachment of up to 100 modules via USB hubs, with specific channel totals depending on the combination of base units and expansion modules (e.g., an OMB-DAQ-56 + OMB-PDQ2 configuration yields 30 DE / 60 SE analog inputs).

Software support includes Personal DaqView for setup, acquisition, and real-time display. Drivers are provided for Visual Basic, Delphi, C++, DASYLab, and LabVIEW.