5500 pages

Applications

Model 550
Low Pressure Transducer
General Service and Submersible

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Tank Level
Reservoir Level
River Level
Hydro-Power
Open Channel Flow
Flood Warning
Process
Waste Water
Clean Room

Benefits
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etra’s Model 550 low pressure transducer
features 3:1 range turndown for field
adjustment from 110% to 32% of the
nominal pressure range, making this unit well
suited to applications that are subject to
overpressure. Adjustment is made via the switch
and potentiometer conveniently located on the
top of the transducer housing.
Utilizing capacitance technology, the Model 550
is designed to measure pressures as low as
10 in. W.C up to 400 in. W.C. (1 psi up to 15 psi)
and features a wide selection of current or
voltage outputs with 0.25% full scale accuracy.
The Model 550 is packaged in a rugged 316
stainless steel housing for use in general
purpose and submersible applications. A male
or female threaded pressure fitting is offered for
general purpose applications, and an open face
style with a KF25 flange is offered for
submersible applications. This open face
architecture keeps the internal bore of the
transmitter as large as possible, making this unit
well-suited to waste water and viscous fluid
applications. A triple sealed cable assembly
assures that water cannot penetrate the sensor
or electronic enclosure, even if the sheath
sustains damage during use.

Principle of Operation
The capacitive sensor is constructed of an
electrically isolated stainless steel electrode
and a ceramic diaphragm, mounted closely
and in parallel to each other. The diaphragm is
capable of slight flexing under applied
pressure. A minute change in applied pressure
alters the gap between the electrode and
diaphragm. This change is detected by a
custom designed ASIC, amplified, and
converted to high-level linear output signal
that is proportional to applied pressure.
The Model 550 circuit is RFI/lightning
protected, virtually eliminating costly field
replacement.
This unit offers high performance, exceptional
long-term service and stable operation, yet is
a cost-effective choice for the most
demanding applications.
Pressure Ranges
Pressure
Range

Proof
Burst
Pressure Pressure

≤85 in. W.C.
86 in.W.C. to 140 in. W.C.
141 in. W.C. to 400 in. W.C.
≤3 psi
3.1 to 5 psi
5.1 to 15 psi

803 in. W.C.
1607 in. W.C.
2025 in. w.C.
29 psi
58 Psi
102 psi

1219 in. W.C.
2410 in. W.C.
4017 in. W.C.
44 psi
87 psi
145 psi

159 Swanson Road, Boxborough, MA 01719/Telephone: 978-263-1400/Fax: 978-264-0292

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Superior Stability
Avoids Down Time
±0.25% FS High Accuracy
NEMA 4/ IP65and NEMA
6/IP68 Rated
3:1 Range Turndown
Fast 5ms Response
Long-Term Service
Exceeding 10 Million
Cycles.
Meets CE Conformance
Standards

When it comes to a product to
rely on - choose the Model 550 .
When it comes to a company to
trust - choose Setra.

ISO
9001:

2000

Certified

Visit Setra On-line:
http://www.setra.com

800-257-3872