CF 126
2
Nov 2001
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DFI 1550: 1 to 4 physical channels, 3/8 DIN case, no limits or peak detector
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DFI 1650: 1 to 4 physical channels, 3/8 DIN case
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DFI 1650PT: 1 to 4 physical channels, portable case
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DFI 1650-3004: 1 to 14 physical channels, 19" rack mount case, 1 to 3 quad-Iine displays
1.3.3 Channel Types
Channels can be one of three types: Input, Output, or Virtual
Input Channels
Input channels are hardware circuit boards with a unique channel number. Currently,
they are available for the following types of sensors:
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Strain-gage sensors, such as unamplified pressure transducers and load cells
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Sensors with voltage outputs
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Sensors with current outputs
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AC-AC LVDTs (Linear Variable Displacement Transducers)
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DC-DC LVDTs
Output Channels
Output channels are hardware circuit boards with a unique channel number. They
include:
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Relay Output channels, which can add additional limits to the standard four (N/A on DFI 1550).
•
DAC Output channels, which provide additional voltage or current outputs.
Virtual Channels
Virtual channels are software-based devices that occupy a channel number, but not a
physical slot, in an instrument.
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Split Display Virtual channels allow the displaying of any two channel's track, peak or valley
values at the same time.
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Mathematics Virtual channels run small programs written in an interpretive language called
SensoCode. This provides great flexibility which allows the DFI Series to do many jobs which
otherwise requires a personal computer or PLC.
1.4 What is Calibration?
1.4.1 Overview
A small integrated circuit is located either inside the transducer, in an in-Iine package between the
instrument and the transducer, or in the connector of a cable. All data necessary to set up the transducer
with the instrument are stored (even linearity data), and setup is automatic when a new transducer is
connected to the instrument.
The Strain Gage Input channel of the DFI Series is designed to operate with Signature Calibration. It will
automatically set itself up with transducers that contain the memory device, but can also be set up using a
front-panel interactive procedure. The Signature Calibration module can also be programmed from the
instrument's front panel.
Calibration is only available with un-amplified strain-gage transducers.
1.4.2 Benefits
The benefits are:
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The transducer's Calibration Record is always located where it is needed most - with the
transducer.
•
The instrument is always set up correctly with the transducer.
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Interchanging of transducers and instruments is a quick process.
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A User Calibration Data area that can be altered by customers to fit their requirements.
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A Factory Calibration Sheet Data area, unalterable by the customer, can be copied back into the
User Calibration Data.
1.4.3 Information Stored
The following information is stored inside transducers equipped with Calibration:
