Setra System Model 869 - Manual (Page 15)

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10.0 GLOSSARY OF TERMS
Atmospheric Pressure - Pressure of the atmosphere at the Earth’s
surface. NIST standard atmospheric pressure = 1.01325 bar.
Burst Pressure - The mazimum pressure that may be applied to the posi-
tive pressure port without rupturing the sensing element.
Capacitive Sensing - Detection and measurement of pressure through
the change in voltage accross a capacitor, one plate of which is a dia-
phragm which deflects slightly with changes in applied pressure.
Differential Pressure - Pressure measurement relative to a reference
pressure. Referred to as pounds per square inch differential (PSID) or
inches of water column differential (WCD).
FS (Full Span or Full Scale) - The range of measured values over which
a transducer is intended to measure, specified by the upper and lower
limits. Ex: 0 to 100 PSIG, FS is 100 PSIG/0 to 5 VDC, 800-1100 MB, FS
is 300 MB.
P/I - Term common to process industries meaning pressure-in/current-out.
Ex: 3-15 PSIG Input to 4-20 mA DC Output.
Pressure Transducer - An electromechanical device for translating fluid
pressure values into voltages across a high-impedence (5k ohms or
greater) load.
Pressure Transmitter - An electromechanical device for translating fluid
pressure values into currents (generally 4-20 mA) into a low-impedence
load.
Proof Pressure - The maximum pressure that may be applied without
changing performance beyond specifications (typically 0.5% FS zero
shift).
Range - The spread between the maximum and minimum pressures
between which the transducer has been designed to operate.
Span - The algebraic difference between the limits of the range. Ex: 0.1
to 5.1 Volts DC, span is 5VDC. Sometimes used to designate full scale
output; i.e. 5 VDC.
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6.31 TEST: Dial Gauge
Differences from General (Diagrams 8 & 9):
-Pressing DO TEST button brings up separate test page with dither control
(Diagram 10).
-Output columns removed from Test Profile/Results window.
6.32 TEST: P-Switch
Differences from General (Diagrams 8 & 9):
-Pressing DO TEST button brings up separate test page with dither control
(See 6.33 Dither Control Page, Diagram 10).
-Output columns removed from Test Profile/Results window.
-O/C column added to indicate the state of the pressure switch.
O - Open
C - Closed
Diagram 9