The Columbia Models SI-702AI and SI-702AIHP are biaxial force balance inclinometers with a 4–20 mA data transmission output circuit. The 4–20 mA system is widely used in industrial settings to send data over long distances in areas where interference from surrounding electrical power lines is a concern.
Both the sensor and the 4–20 mA line driver are powered by a single +15 volt supply. These devices can deliver reliable tilt data even in high-vibration conditions thanks to special desensitization circuitry. The SI-702BI and SI-702BIHP Biaxial Inclinometers have similar features and provide an output voltage as well as current.
- 4–20 mA output
- High performance and low cost
- Biaxial Tilt Sensor
Image Credit: Columbia Research Laboratories, Inc.
Specifications
Operational
Table 1. Source: Columbia Research Laboratories, Inc.
| Operational |
SI-702AI |
SI-702AIHP |
| Ranges Available |
±15º, ±30º, ±45º, ±90º |
±5º, ±15º, ±30º, ±45º, ±90º |
| Output Current |
4-20 mA |
| Output Function |
Io = 12 + K Sin θ (mA) ±0.5% of Normal
Into a Maximum Load of 600 Ohms |
| Excitation |
+15 ±1 VDC
<50 mA |
| Output Impedance |
50 Megohm Typical |
| Non-Linearity |
±0.2% F.R. |
±0.1% F.R. |
| Non-Repeatability |
±0.1% F.R. |
| Scale Factor Tolerance |
±1% |
| Scale Factor Temp Coefficient |
±0.02% / Deg C |
| Zero Bias |
12 ±0.02 mA |
| Zero Bias Temp. Coefficient |
±0.002% F.R. / Deg C |
| Resolution |
0.01% F.R. |
0.001% F.R. |
| Bandwidth |
0 to 3 Hz (-18 dB / Octave Rolloff) |
| Orthogonal Sensitivity |
<1% |
| Case Alignment |
±0.5 Deg |
| Vibration Overload vs. Frequency |
See Figure 1 |
See Figure 2 |
Environmental
Table 2. Source: Columbia Research Laboratories, Inc.
| Environmental |
SI-702AI |
SI-702AIHP |
| Temperature, Operating |
-40 to +85 Deg C |
| Temperature, Storage |
-40 to +85 Deg C |
| Random Vibration (2 to 2,000 Hz) |
5 G RMS, 0.25” Disp. D.A. |
15 G RMS, 0.25” Disp. D.A. |
| Shock Survival |
125 G, 5 mSec |
1000 G, 1 mSec |
| Humidity |
95% R.H. |
Physical
Table 3. Source: Columbia Research Laboratories, Inc.
| Physical |
SI-702AI |
SI-702AIHP |
| Weight |
12 Oz (340.2 Gm) |
| Size |
4.06 In L x 3.125 In W x 2.13 In H
(10.31 cm L x 7.94 cm W x 5.41 cm H) |
| Case Material |
Anodized Aluminum |
| Sealing |
Environmental |
| Electrical Interface |
Connector MS3443412-10P or Equiv. |
| Mating Connector (Optional) |
PT06A-12-10S(SR) or Equiv. |
Typical Frequency Response
SI-702AI & SI-702AIHP
Image Credit: Columbia Research Laboratories, Inc.
Vibration Overload vs. Frequency
Figure 1. Image Credit: Columbia Research Laboratories, Inc.
Figure 2. Image Credit: Columbia Research Laboratories, Inc.
Output Connector Pin Functions
Table 4. Source: Columbia Research Laboratories, Inc.
| SI-702AI and SI-702AIHP |
| Pin |
Function |
Pin |
Function |
| A |
+15 VDC Power |
F |
Spare |
| B |
Power Ground |
G |
Spare |
| C |
Current Return |
H |
Spare |
| D |
Io – X Axis |
J |
Spare |
| E |
Io – Y Axis |
K |
Spare |