Cole Parmer 16 Series, Руководство по эксплуатации

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Differential Pressure Gauges
:
The differential pressure gauge is designed to measure a pressure ratio between two points in the line.
There are a variety of applications for this device. One of the most common is to measure the difference
in pressure across some sort of element that changes resistance to flow over time, such as a filter, or
one that changes area with time as would happen with orifice testing. The gauge has two sensing ports
which are piped to the upstream and downstream sides of the pressure drop of interest in the system.
These two ports run either to two separate pressure sensors or for low differential pressures – they may
be run to the two legs of a single differential pressure sensor. The higher (upstream) pressure is applied
to the left port and the lower (downstream) pressure is applied to the right port.
Figure 17. Differential Pressure Gauge
Differential Pressure Controllers
:
The differential pressure controller is designed to change the flow to allow the control of a pressure
ratio between two points in the line. There are a variety of applications for this device. One of the most
common is to control the difference in pressure across some sort of element that changes resistance to
flow over time, such as a filter or one that changes area with time as would happen with orifice testing.
To accomplish differential pressure control, the controller has two sensing ports which are piped to the
upstream and downstream sides of the pressure drop in the system. These two ports run either to two
separate pressure sensors or for low differential pressures – they may be run to the two legs of a single
differential pressure sensor. The controller itself changes the flow to the two sensing ports until the
difference between the two pressures matches the set-point.
Figure 18. Differential Pressure Controller
P1
P2
P1
P2