Emerson Tescom ER5000 Series User Manual page 55

ER5000 — Glossary of Terms
Pilot Regulator
Device that controls pressure to the actuation port of a dome
loaded or air actuated Regulator. In its simplest form, the ER5000
is a pilot regulator.
Negative Bias
For Dome Loaded Regulators, the amount of
beyond the desired setpoint that is necessary to overcome the
physical resistance of the Sensing Element
or piston o-ring) and initiate a dynamic response from the
regulator. For example, to initiate a 1 psig / 0.07 bar setpoint, it
may initially require 26 psig / 1.8 bar of
regulator valve and allow flow. Once dynamic response has been
initiated, the dome loaded regulator tracks at a 1:1 relationship
between pilot pressure and Control
25 psig / 1.7 bar of pilot pressure will result in a jump from 1 psig
to 26 psig / 0.07 bar to 1.8 bar in control pressure.
Please discuss with your TESCOM™ representative if you
are using a dome loaded regulator with the ER5000, as the
amount of negative bias varies among different dome loaded
regulator models.
Loading Force
(such as a diaphragm
Pilot Pressure to open the
Pressure, so an additional
Piston
One type of Sensing Element. Used for high pressure applications,
up to 30,000 psig / 2068 bar.
psia (absolute pressure)
A measure of pressure in pounds per square inch (psi) that is
referenced to zero absolute pressure.
psig (gauge pressure)
A measure of pressure in pounds per square inch (psi) that is
referenced to atmospheric pressure.
Ratio Actuator
Device that amplifies the force generated by the
(Loading Force) in air actuated Regulators. Allows a relatively
small Pilot Pressure to regulate a
times greater. TESCOM air actuated regulators are available with
ratios from 2:1 to 375:1.
Repeatability
The ability of a Regulator to return to the same
being subjected to various flow demands.
Loading Element
Control Pressure that is many
Set Pressure after
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