Stand Alone Inclinometer

SCA115T and SCA125T Series

FEATURES

• Silicon 3D MEMS sensor

• RS-485 serial interface

• 11 bit resolution

• Operating temperature range -40...+85°C

• Inclination and temperature output

• Long term stability < 0,02°

• Shock resistance >20 000g

• 30x30x13mm size, single or dual axis

• Horizontal or vertical mounting

BENEFITS

• Excellent long term stability

• Sensing element controlled frequency response

• Outstanding shock durability

• Harsh environment robustness

APPLICATIONS

• Platform tilt measurement

• Equipment and instrument condition monitoring

• Inclination based position measurement

• Rotational orientation measurement (dual axis)

For customised product please contact VTI Technologies

Figure 1. Positions

Notes:

• It is important that the part is parallel to the mounting plane, and that the output equals the zero value when sensor is in zero position.

• Zero position: Please note the picture above which provides information on how the output of the accelerometer behaves in different

circumstances when assembled. Please also note that you can rotate the part around the measuring plane for optimum mounting location

MEASURING DIRECTIONS

Negative incl.,

Zero position,

Positive incl.

X-axis

Y-axis

Positive incl.,

Zero position,

Negative incl.

Earth’s gravity

Mounting position 1

(Horizontal)

Mounting position 2

(Vertical)

Mounting position 1

Mounting position 2

Deviation

Deviation

Note 1.

The measuring range is limited by the sensitivity and offset.

Note 2.

Offset specified as Output @ 0°.

Note 3.

The frequency response is determined by the sensing element’s internal gas damping.

The output has true DC (0Hz) response.

Note 4.

The cross-axis sensitivity determines how much inclination, perpendicular to the measuring

axis, couples to the output.

Note 5.

Mounting position should be calibrated. See measuring positions.

ELECTRICAL CHARACTERISTICS

Parameter

Condition

Min.

Typ

Max.

Units

Supply voltage

7

16

35

V

Current consumption

20

mA

Output

RS-485, half-duplex

kΩ

Data transfer speed

11 bit word

10

Hz

PERFORMANCE CHARACTERISTICS

Parameter

Condition

SCA115T-D03

SCA125T-D06

SCA125T-D08

Units

°

Measuring axis

(see “Directions”)

X

X-Y

X-Y

Output at 0°, HEX 03FF

FS/2

FS/2

FS/2

Offset temperature error

0…70°C

°

-25...85°C

°

@ 0° (offset position)

0,035

0,07

0,035

°/LSB

11

11

11

Bit/FS

Sensitivity

Sine of inclination

30

90

30

°/FS

0…70°C

%

-25...85°C

%

Nonlinearity

Sinus output

0,1

N/A

0,1

°

18

18

18

Hz

4

4

4

%

Typical values @ ambient temperature unless otherwise specified.

Rev. 4 Jan 2005

VTI Technologies reserves the right to modify this specification without prior notice.

Single or dual axis RS-485 output