Setra 270 Data sheet

Model 270

SETRACERAMTM for Barometric, Gauge or Absolute Pressure

Barometric Pressure: 600-1100 hPa/mb, 800-1100 hPa/mb

Absolute: 0 to 10, 20, 50, 100 psia / Gauge Pressure: 0 to 5, 10, 20, 50, 100 psig

Non-condensing Air or Gas

or many years, high accuracy environ­mental and test & measurement appli­cations around the world have relied on

F

the consistent performance of the Setra Model
270 pressure transducer. Applications range
from remote weather monitoring and
avionics systems, endorsed by government
agencies, to crucial compensation for
barometric pressure variations in laser
interferometers.

Long-term reliability and stability in such
demanding application environments are

achieved in the 270 with the combination of
the SETRACERAM™ capacitive sensor and
Setra’s proprietary custom IC analog circuit.

The fundamentally simple design and thermally
stable glass fused ceramic sensing capsule is
coupled with the sophisticated capacitance
charge-balance IC circuit where accurate signal
conditioning and environmental compensation
is performed. Standard accuracy is 0.05% Full
Scale, end point method. Higher accuracy and
thermal specifications are also available.

Type of Pressure Maximum

Pressure Range Pressure

Barometric 800 to 1100 hPa/mb 20 psia

600 to 1100 hPa/mb

Absolute 0 to 10, 20, 50, 1.5 x rated

100 psia

Gauge 0 to 5, 10, 20, 1.5 x rated

50, 100 psig

Applications

■ High Accuracy Barometric

Pressure Measurement

■ Weather and

Environmental Data

■ Data Buoys and Remote

Weather Stations

■ Engine Test Cells

■ High Accuracy Transfer

Standard for Calibration

■ CE Mark Compliance

Features

● SETRACERAM

● High Accuracy, ± 0.05% FS

● ±0.03% FS Optional

Accuracy

● Repeatability Within

0.01% FS

● Excellent Long-Term

Stability

● Low Power Consumption

● Instant Warm-Up

● Fast Response

When it comes to a product to rely
on - choose the Model 270. When it
comes to a company to trust ­choose Setra.

Visit Setra Online:

http://www.setra.com

TM

Sensor

ISO

900 1

✓

Certified

NOTE: Setra adheres to strict quality standards including
ISO 9001 and ANSI-Z540-1. The calibration of this product is
NIST traceable.

U.S. Patent nos. 4093915, 4168518

159 Swanson Rd., Boxborough, MA/Telephone: [phone]/Fax: [phone]

800-257-3872

Model 270 Specifications

Performance Data

Accuracy* <±0.05% FS
Non-Linearity

End Point ±0.05% FS
Best Fit Straight Line ±0.03% FS

Hysteresis 0.01% FS
Non-Repeatability 0.01% FS
Resolution Infinite, limited only by

output noise level
(0.005% FS)

Thermal Effects**
Compensated Range °F (°C) +30 to +120

(-1 to +49)

Thermal Zero Shift

Barometric <±0.2% FS/100°F

(±0.18% FS/50°C)

Other Ranges <±0.1% FS/100°F

(±0.09% FS/50°C)

Thermal Coefficient Sensitivity <±0.1% FS/100°F

(±0.09% FS/50°C)

Long Term Stability <± 0.1% FS over 6

months at 70°F
Static Acceleration Effect <±0.01% FS/G
Warm-up <±0.04% FS shift

after 20 minutes at

constant temperature

and pressure
Time Constant < 10 milliseconds to

reach 90% final output

with step function

pressure input

* RSS of Non-Linearity, Hysteresis, and Non-Repeatability.
Higher accuracy units available on special order.
** Units calibrated at nominal 70°F. Maximum thermal error computed from
this datum.

Environmental Data

Temperature
Operating °F (°C) 0 to +175 (-18 to +80)
Storage °F (°C) -65 to +250 (-54 to +120)
Vibration 2g from 5Hz to 500Hz
Acceleration 10g
Shock 50g Operating, 1/2 sine 10 ms
Pressure fitting 1/8" -27 NPT Internal
Electrical connection 2-foot Multi-conductor Cable
Weight (approx.) 9 ounces (0.25 Kgm)

Electrical Data

Electrical Circuit* 4-Wire ( +Exc, -Exc, +Out, -Out)
Excitation** 22 to 32 VDC

Fully protected against miswiring
Output*** 0 to 5 VDC****
Isolation The insulation resistance between

all signal leads tied together and

case ground is 100 megohms

minimum at 25 VDC.
Output Impedance <5 ohms
Output Noise <200 microvolts RMS

(0 Hz to 100 Hz).
Current Consumption 8 mA (0.2 Watts)

*For best performance, either negative excitation or negative output should
be connected to case (ground). Both leads cannot be connected to case
(ground). Units calibrated at the factory with negative excitation
connected to case.
**Internal regulation minimizes effect of excitation variation, with
< ± 0.005% FS output change. Will operate on 28 VDC aircraft power
per MIL-STD-704A and not be damaged by emergency power conditions.
*** Calibrated into a 50K ohm load, operable into a 5000 ohm load or greater.
**** Zero output factory set to within ±5 mV.
Span (Full Scale) output factory set to within ±5 mV.

Options

Electrical Options

623 12 VDC excitation (11 to 15 VDC)

Performance Options
703 Compensated temperature, -13°F to +150°F

(±0.13% FS/100°F zero and span effect).
Cannot be ordered with option 707.

707 ±0.03% FS (RSS) Accuracy with ±0.027% FS

Linearity (End Point Method). Cannot be
ordered with option 703.

Mechanical Options
803-825 Up to 25 ft. of cable can be supplied.

Please specify cable length when

ordering (i.e. 805 for 5 ft. cable).
865 NEMA 4 Weather Proof Enclosure
911 Etched Metal Stainless Steel Tag

Special Range
SR Special Range (Specify Range Required).

Pressure Media

Non-condensing air or gas compatible with hard anodized
aluminum, alumina ceramics, gold, fluorocarbon elastomer
sealant & Buna-N O-Ring.

Specifications subject to change without notice.

Outline Drawings

2.084

52.93

While we provide application assistance on all Setra products, both
personally and through our literature, it is the customer’s responsibility
to determine the suitability of the product in the application.

0.516

13.11

IN

MM

1.055

26.79

1.055

26.79

0.625

15.87

6-32UNC-2B
.180 MIN FULL THRD
(4 HOLES)

1/8-27NPT

PORT

0.188

4.77

0.312

7.92

1.093

27.76

2.00

50.8

CABLE

2’ LONG

0.312

7.92

1.500

38.1

0.125

3.175

0.875

22.23

0.156 MOUNTING HOLES
4 PLACES

2.720

69.08

159 Swanson Road, Boxborough, MA 01719/Tel: [phone];

Toll Free: 800-257-3872; Fax: [phone]; email: [e-mail]

3.000

76.2

SSP270 Rev.C 12/05/02

3.250

82.55