B-14
TERM DEFINITION
DB1
Acronym for Data Base 1. This refers to the previous data base structure used
to store data in Totalflow products.
DB2
Acronym for Data Base 2. This refers to the current data base structure used to
store data in Totalflow products.
DC
See Direct Current
DCD
Communication abbreviation for Data Carrier Detect
DCS/PLC
Distribution Control System/Programmable Logic Controller
DDE
See Digital Data Exchange. Also called Dynamic Data Exchange. May refer to
Totalflow’s DDE Server TDS32.
Dead Weight Tester
Portable pressure tester used to check calibration and to calibrate AMU’s
utilizing a system of calibrated weights.
De-bounce
De-bouncing is any kind of hardware device or software that ensures that only
a single signal will be acted upon for a single opening or closing of a contact.
When you press a key on your computer keyboard, you expect a single contact
to be recorded by your computer. In fact, however, there is an initial contact, a
slight bounce or lightening up of the contact, then another contact as the
bounce ends, yet another bounce back, and so forth. A similar effect takes
place when a switch made using a metal contact is opened. The usual solution
is a de-bouncing device or software that ensures that only one digital signal can
be registered within the space of a given time (usually milliseconds)
Decane (C10H22)
A hydrocarbon (Alkane) flammable colorless liquid with ten carbon atoms.
Decibel
A logarithmic measure of the ratio of two signal levels. A practical unit of gain.
Decimal
A numbering system based on 10.
Default
A value assigned or an action taken automatically unless another is specified.
Degree
An incremental value in the temperature scale, i.e., there are 100 degrees
between the ice point and the boiling point of water in the Celsius scale and
180°F between the same two points in the Fahrenheit scale.
Delivery Point
Point at which gas leaves a transporter's system completing a sale or
transportation service transaction between the pipeline company and a sale or
transportation service customer.
Demand Day
That 24-hour period specified by a supplier-user contract for purposes of
determining the purchaser's daily quantity of gas used (e.g., 8 AM to 8 AM,
etc.). This term is primarily used in pipeline-distribution company agreements. It
is similar to, and usually coincides with, the distribution company "Contract
Day".
Demand Load
The rate of flow of gas required by a consumer or a group of consumers, often
an average over a specified short time interval (cf/hr or Mcf/hr). Demand is the
cause; load is the effect.
Demand Meters
A device which indicates or records the instantaneous, maximum or integrated
(over a specified period) demand.
Demand, Average
The demand on a system or any of its parts over an interval of time, determined
by dividing the total volume in therms by the number of units of time in the
interval.
Density
Mass per unit Volume: D=MV
Desaturization
Doesn’t cause the composition of the gas to change, enabling a more
representative sample of gas.
Detector Bead
See Thermal Conductivity Detector.
Deviation
The difference between the value of the controlled variable and the value at
which it is being controlled.
Summary of Contents for XRC6490
Page 1: ...2100802 001 AB TOTALFLOW XSeries Remote Controller User s Manual ...
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Page 19: ...1 5 Standard Enclosure Cont RC 6790 X Figure 1 2 Model XRC6790 Continued on Next Page ...
Page 41: ...1 27 Totalflow Input Output Modules Cont Figure 1 16 XRC6990 Inside View ...
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Page 86: ...4 12 Replacing XRC 195 Board Cont Figure 4 5 XRC Board Connections ...
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Page 112: ...5 24 12V Communication Supply Voltage Test Cont Figure 5 9 XRC 195 Communication Wiring ...
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