ETC 2B31

High Performance, Economy
Strain Gage/RTD Conditioners
Models 2B30 and 2B31
Low Cost
Complete Signal Conditioning Function
Low Drift: 0.5µ/°C max ("L"); Low Noise: 1µV p-p max
Wide Gain Range: 1 to 2000V/V
Low Nonlinearity: 0.0025% max ("L")
High CMR: 140dB min (60Hz, G =1000V/V)
Input Protected to 130V rms
Adjustable Low Pass Filter: 60dB/Decade Roll-Off (from 2Hz)
Programmable Transducer Excitation: Voltage (4V to 15V @
100mA) or Current (100µA to 10mA)
Measurement and Control of:
Pressure, Temperature, Strain/Stress, Force, Torque
Instrumentation: Indicators, Recorders, Controllers
Data Acquisition Systems
Microcomputer Analog I/O
Models 2B30 and 2B31 are high performance, low cost, com pact signal
conditioning modules designed specifically for high accuracy interface
to strain gage-type transducers and RTD’s (resistance temperature
detectors). The 2B31 consists of three basic sections: a high quality
instrumentation amplifier; a three-pole low pass filter, and an adjustable
transducer excitation. The 2 B30 has the same amplifier and filter as the
2B31, but no excitation capability.
Available with low offset drift of 0.5µV/°C max (RTI, G = 1000V/V)
and excellent linearity of 0.0025% max, both models feature guaranteed
low noise performance (1µV p-p max), and outstanding l40dB common
mode rejection (60Hz, CMV = ±10V, G = 1000V/V) enabling the
2B30/2B31 to maintain total amplifier errors below 0.1% over a 20°C
temperature range. The low pass filter offers 60dB/decade roll-off from
2Hz to reduce normal-mode noise bandwidth and improve system
signal-to-noise ratio. The 2B31's regulated transducer excitation stage
features a low output drift (0.01 5%/°C max) and a capability of either
constant voltage or constant current operation.
Gain, filter cutoff frequency, output offset level and bridge excitation
(2B31) are all adjustable, making the 2B30/2B31 the industry's most
versatile high-accuracy transducer-interface modules. Both models are
offered in three accuracy selections, J/K/L, differing only in maximum
nonlinearity and offset drift specifications.
in harsh industrial environments, such characteristics as high CMR,
input protection, low noise, and excellent temperature stability make
2B30/2B31 ideally suited for use in indicators, recorders, and
The combination of low cost, small size and high performance of the
2B30/2B31 offers also exceptional quality and value to the data
acquisition system designer, allowing him to assign a conditioner to
each transducer channel. The advantages of this approach over low
level multiplexers include significant improvements in system noise
and resolution, and elimination of crosstalk and aliasing errors.
High Noise Rejection: The true differential input circuitry with high
CMR (140dB) eliminating common-mode noise pickup errors, input
filtering minimizing RFI/EMI effects, output low pass filtering
(fc=2Hz) rejecting 50/60Hz line frequency pickup and series-mode
Input and Output Protection: input protected for shorts to power
lines (130V rms), output protected for shorts to ground and either
Ease of Use: Direct transducer interface with minimum external parts
required, convenient offset and span adjustment capability.
Programmable Transducer Excitation: User-programmable
adjustable excitation source-constant voltage (4V to 15V @ l00mA) or
constant current (100µA to l0mA) to optimize transducer performance.
Adjustable Low Pass Filter: The three-pole active filter (fc=2Hz)
reducing noise bandwidth and aliasing errors with provisions for
external adjustment of cutoff frequency.
The 2B30/2B31 may be easily and directly interfaced to a wide variety
of transducers for precise measurement and control of pressure,
temperature, stress, force and torque. For applications
Information furnished by Intronics is believed to be accurate and reliable. However, no
responsibility is assumed by Intronics for its use; nor for any infringements of patents or
other rights of third parties which may result from its use. No license is granted by
implication or otherwise under any patent or patent rights of Intronics.
1400 Providence Highway, Building #2
Norwood, MA 02062
Phone (781) 551-5500
FAX (781) 551-5555