MREL DATA TRAP II, Operation Manual

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DataTrap II™ Operations Manual - Edition 5.4
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6.1 Introduction To Recording DC Voltage Signals
The DataTrap II™ Data/VOD Recorder is capable of recording DC voltage signals on 1 to 8 channels. Additionally, if the DataTrap II™
Data/VOD Recorder VOD Upgrade has been installed, any channel can be used to record VOD data simultaneous with the recording of
voltage signals on other channels. Details on the procedure for recording VOD data are provided Chapter 5 .
The DataTrap II™ Data/VOD Recorder and associated DAS™ Data Acquisition Suite Software are specifically designed to be used with
gauges, power supplies and signal conditioning equipment producing DC voltage signals in the -10 to +10 VDC range or lower. The
channels can be individually set to accept a variety of uni-polar and bi-polar voltage ranges. The 0-2.5, 0-5, 0-7.5 and 0-10 volt ranges
refer to the uni-polar setting commonly used to measure slow changing events such as temperature recordings. The ±2.5, ±5, ±7.5, and
±10 volt ranges refer to the bipolar mode which is frequently used to record faster events such as explosion & detonation pressures, blast
vibrations, overpressures, air blast, strains, etc.
Gauges or transducers used to measure parameters commonly studied in blast situations are commercially available. Examples are the
tourmaline and carbon resistor gauges to measure cross-borehole propagation, the PVDF transducers to measure detonation pressures,
various PCB gauges to measure blast over-pressures as well as various types of thermocouples to measure temperatures. The
DataTrap
II™ Data/VOD Recorder channels do not apply any voltage or current to the gauges or transducers when in DC Input mode. Should they
require excitation signals to operate, the appropriate power supply(s) should then be acquired from the gauge manufacturers or suppliers.
The DAS™ Data Acquisition Suite automatically displays the recorded data as graphs of voltage versus time. The Software includes menu
functions that allow the Operator to apply equations to convert the voltage data into graphs of engineering units versus time. The type of
engineering units depends on the type of gauge being recorded and is easily defined by the Operator. For more detail, please review
the
DAS™ Data Acquisition Suite Manual.
6.2 Connecting Gauges To The DataTrap II™ Data/VOD
Recorder
The equipment and supplies that are required to record voltage signals from gauges are:
1. The DataTrap II™ Data/VOD Recorder System.
2. Gauges (maximum 8).
3. Coaxial cable (type RG-58 is recommended) - sufficient length to run between the
DataTrap II™ Data/VOD Recorder location and
the gauge.
4. Wire cutters and electrical tape.
This Chapter provides the Operator with detailed instructions on connecting the gauges to the
DataTrap II™ Data/VOD Recorder and setting the DataTrap II™ Data/VOD Recorder hardware
to record the voltage signals produced by the gauges.
Overview