3B20 AC Strain Gage, Torque Transducer Input
3B20 AC Strain Gage, Torque Transducer Input

3B Series Custom-Ranging Program
Externally-programmable Model 3B20-00, enables the user to configure a special input range, including tare weight suppression, by using the optional plug-on AC1310 ranging card, which houses user-supplied resistors to determine zero and span. To facilitate selecting resistors, a Windows® program, 3B-CUSTOM, calculates resistor values based on the user-desired input/output ranges.
Inside the 3B20 Series Module
The 3B20 input and AC bridge excitation output terminals are protected for up to 130 V rms. The excitation amplitude and frequency can be specified with the Model 3B20-CUSTOM or user configured with Model 3B20-00 and an optional plug-on Model AC1310 ranging card. Both the voltage and current outputs can be independently adjusted for a minimum of ±1 V for the zero and 25% of the span range with front-panel user-accessible potentiometers. In addition, phase shifts of up to 37.25° between excitation signal and the output signal from the strain gauge or torque transducer can be compensated via front-panel screw terminal adjustments.
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Figure 1. 3B20 Functional Block Diagram |
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Figure 2. 3B20 Input Field Connections |
Input Type |
Dual Outputs |
1.5 mV rms to 150 mV rms |
-10 V to +10 V |
Full 4-Arm AC Strain Gage |
4 mA to 20 mA or 0 to 20 mA |
AC Torque Transducer |
Model | Excitation Voltage |
Excitation Frequency |
Input Range | Sensitivity | Output Ranges1 |
|
Order Now | 3B20-00 |
Externally Programmable2 |
Externally Programmable2 |
Externally Programmable2 |
Externally Programmable2 |
-10 V to +10 V & 0 mA to 20 mA |
Order Now |
3B20-01 |
5 V rms |
3 kHz |
20 mV rms |
2 mV rms/V | -10 V to +10 V & 0 mA to 20 mA |
3B20-Custom |
* |
* |
* |
* | * |
1 Output current range may be user programmed to 4 mA to 20 mA using jumper supplied.
2 Requires AC1310 ranging card.
* Custom Input/Output ranges are available. Refer to configuration guide.
(typical @ +25°C and ±15 V dc, and +24 V dc Power)
Description | Model 3B20 |
Input Range |
|
Standard Range |
Refer to Model Table |
Custom Ranges |
Vin = 1.5 mV rms to 150 mV rms Vexc = 2 V rms to 10 V rms Vexc freq. = 1 kHz to 10 kHz |
Output Range |
|
Voltage (RL > 2 KΩ) |
-10 V to +10 V |
Current (RL = 0 to 850Ω)1 |
4 mA to 20 mA or 0 mA to 20 mA |
With Input Overload |
40 mA, maximum |
Accuracy2 | |
Initial @ +25°C |
±0.1% Span |
Nonlinearity2 |
±0.05% Span |
Stability vs. Temperature |
|
Voltage Output |
|
Zero | ±0.005% of Span/°C |
Span | ±0.01% of Span/°C |
Current Output3 |
|
Zero | ±25 ppm of Span/°C |
Span | ±25 ppm of Reading/°C |
Bridge Excitation |
|
Voltage4 |
2 V rms to 10 V rms |
Voltage, tolerance |
±2.5% |
Frequency4 | 1 kHz to 10 kHz, ±15% |
Drive |
Up to 20 mA rms, minimum |
Harmonic Distortion |
< 0.5% |
Span Calibration Adjustment Range4 |
±25% of span, minimum |
Zero Calibration Adjustment Range4 |
±1 V, minimum |
Phase Adjustment Range5 |
0 to 4.25° minimum @ 1 kHz 0 to 14° minimum @ 3.28 kHz 0 to 37.25° minimum @ 10 kHz |
Input Bias Current |
+10 nA |
Input Resistance |
100 MΩ |
Bandwidth, -3 dB |
100 Hz |
Output Rise Time, 10% to 90% Span |
200 ms |
Input Protection, Signal and Excitation Voltage |
|
Continuous |
130 V rms maximum |
Transient | ANSI/IEEE C37.90.1-1989 |
Voltage Output Protection | Continuous Short to Ground |
Current Output Protection |
130 V rms, continuous |
Power Supply Voltages5 |
|
±15 V dc Supplies |
|
Rated Operation | ±(13 V dc to 18 V dc) |
Current | ±65 mA |
Sensitivity | ±0.03% span/V |
+24 V dc Loop Supply |
|
Rated Operation | +13.5 V dc to +30 V dc |
Current | +27 mA @ lout = 20 mA |
Sensitivity | ±0.001% span/V |
Mechanical Dimensions |
3.15" x 3.395" x 0.775" (80.0 mm x 86.2 mm x 19.7 mm) |
Environmental |
|
Temperature Range |
|
Rated Performance | -25°C to +85°C |
Storage | -55°C to +85°C |
Relative Humidity, 24 hours |
0 to 95% @ +60°C noncondensing |
RFI Susceptibility |
±0.5% Span error @ 400 MHz, 5 Watt, 3 ft |
1 For a 0 mA to 20 mA range, a typical minimum output current is 10 µA.
2 Includes the combined effects of repeatability, hysteresis, and nonlinearity.
3 With respect to the voltage output.
4 A wide range of custom zero suppression and span is available with the 3B20-00 model, using the AC1310 ranging card.
5 +24 V dc loop power is required for driving the current output at loads up to 850Ω. If a current output load of 400Ω or less is applied, +15 V dc is sufficient for loop power. If only voltage output is used, loop power is not required.
Specifications subject to change without notice.