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ROC800-Series Instruction Manual
Revised Jul-14
Glossary
A-3
D
(continued)
DRTU
A primary component of the Distributed RTU Network, consisting of a FB107 chassis
housing a focused functionality CPU and a Network Radio module (NRM). The DRTU
collects process variables from one or more wellheads and transmits the signals
throughout the designed network.
DSR
Data Set Ready modem communications signal.
DTE
Data Terminal Equipment.
DTR
Data Terminal Ready modem communications signal.
Duty Cycle
Proportion of time during a cycle that a device is activated. A short duty cycle
conserves power for I/O channels, radios, and so on.
DVM
Digital voltmeter.
DVS
Dual-Variable Sensor. A device that provides static and differential pressure inputs to a
ROC.
E
EDS
Electronic Static Discharge.
EEPROM
Electrically Erasable Programmable Read-Only Memory, a form of permanent memory
on a ROC.
EFM
Electronic Flow Metering or Measurement.
EIA-232
(RS-232)
Serial Communications Protocol using three or more signal lines, intended for short
distances. Concerning RS232D and RS232C, the letters C or D refer to the physical
connector type. D specifies the RJ-11 connector where a C specifies a DB25 type
connector.
EIA-422
(RS-422)
Serial Communications Protocol using four signal lines.
EIA-485
(RS-485)
Serial Communications Protocol requiring only two signal lines. Can allow up to 32
devices to be connected together in a daisy-chained fashion.
EMF
Electro-Motive Force.
EMI
Electro-Magnetic Interference.
ESD
Electro-Static Discharge.
EU
Engineering Units. Units of measure, such as MCF/DAY.
F
FCC
Federal Communications Commission. See
http://www.fcc.gov.Firmware
Internal software that is factory-loaded into a form of ROM. In a ROC, the firmware
supplies the software used for gathering input data, converting raw input data values,
storing values, and providing control signals.
FlashPAC
module
ROM and RAM module for a ROC300-Series unit that contains the operating system,
applications firmware, and communications protocol.
Flash ROM
A type of read-only memory that can be electrically re-programmed. It is a form of
permanent memory (requires no backup power). Also called Flash memory.
FloBoss
A microprocess-based device that provides flow calculations, remote monitoring, and
remote control. A FloBoss is a type of ROC.
FM
Factory Mutual.
Force
Write an ON/OFF, True/False, or 1/0 value to a coil.
F
OUNDATION
™
Fieldbus
An open architecture for information integration, managed by the Fieldbus Foundation
(www.fieldbus.org).
FPV
Compressibility Factor.