162 / 182
ROC800-Series Instruction Manual
Revised Jul-14
Glossary
A-7
type of duplex.
PSTN
Public Switched Telephone Network.
PT
Process Temperature.
PTT
Push-to-Talk signal.
Pulse
Transient variation of a signal whose value is normally constant.
Pulse Interface
module
A module that provides line pressure, auxiliary pressure, and pulse counts to a ROC.
PV
Process Variable or Process Value.
R
Rack
A row of slots on a ROC into which I/O modules can be plugged. Racks are given a
letter to physically identify the location of an I/O channel (such as “A” for the first rack).
Built-in I/O channels are assigned a rack identifier of “A” while diagnostic I/O channels
are considered to be in “E” rack.
RAM
Random Access Memory. RAM is used to store history, data, most user programs, and
additional configuration data.
RBX
Report-by-exception. RBX always refers to Spontaneous RBX in which the ROC
contacts the host to report an alarm condition.
RR
Results Register; stores the Signal Value Analog (SVA).
RFI
Radio Frequency Interference.
RI
Ring Indicator modem communications signal.
ROC
Remote Operations Controller microprocessor-based unit that provides remote
monitoring and control.
ROCLINK 800
Microsoft® Windows®-based software used to configure functionality in ROC units.
ROM
Read-only memory. Typically used to store firmware. Flash memory.
Rotary Meter
A positive displacement meter used to measure flow rate, also known as a Roots
meter.
RTC
Real-Time Clock.
RTD
Resistance Temperature Detector.
RTS
Ready to Send modem communications signal.
RTU
Remote Terminal Unit.
RTV
Room Temperature Vulcanizing, typically a sealant or caulk such as silicon rubber.
RS-232
Serial Communications Protocol using three or more signal lines, intended for short
distances. Also referred to as the EIA-232 standard.
RS-422
Serial Communications Protocol using four signal lines. Also referred to as the EIA-422
standard.
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. Also referred to as the
EIA-485 standard.
RX or RXD
Received Data communications signal.
S
SAMA
Scientific Apparatus Maker’s Association.
SCADA
Supervisory control and data acquisition; referring to a computer system that monitors
and controls oil and gas pipeline systems.