7B41 ISOLATED, VOLTAGE OR CURRENT INPUT

Functional Description

The 7B41 is a single-channel signal conditioning module that interfaces, amplifies and filters unipolar and bipolar voltage inputs and provides a protected precision output of either +1 V to +5 V or 0 V to +10 V. Model 7B41 features a nonlinearity of ±0.02% maximum and an accuracy of ±0.1% maximum (±0.01% typical). To accurately measure low level signals in electrically noisy environments, 1500 V rms of galvanic transformer-based isolation with a common mode rejection (CMR) of 110 dB @ 50/60 Hz and a normal mode rejection (NMR) of 100 dB @ 50/60 Hz are provided. Rated to operate with a nominal +24 V DC supply, Model 7B41 is mix-and-match and hot-swappable with other 7B Series input modules, so it can be inserted or removed from any socket in the same backplane without disturbing system power.

Inside the 7B41 Series Module

The floating differential input of Model 7B41 is fully protected up to 240 V rms line voltage. A one-pole 10 KHz filter preconditions the input signal prior to amplification by a low drift input amplifier. Amplitude modulation is used to implement transformer isolation (1500 V rms input-to-output and power). Isolated front-end circuitry power is supplied by a DC/DC converter. The output section contains a four pole low pass filter (-3 dB @ 10KHz), a buffer amplifier and a power oscillator. The two-pole output filter and subsequent buffer ensures that a low noise, low impedance (<1Ω ) signal is available at the output to drive loads of 2 kΩ minimum.

Figure 1. 7B41 Functional Block Diagram

Input Types

±5V to ±50 V

Output Options

+1 V to +5 V
0 V to +10 V

Figure 2. 7B41
Input Field Connections

7B41 Models Available

	Model	Input Range	Output Range
Order Now	7B41-01-1	0-10V	1-5V
Order Now	7B41-01-2	0-10V	0-10V
Order Now	7B41-02-1	+/-5V	1-5V
Order Now	7B41-02-2	+/-5V	0-10V
Order Now	7B41-03-1	+/-10V	1-5V
Order Now	7B41-03-2	+/-10V	0-10V
Order Now	7B41-04-1	0-5V	1-5V
Order Now	7B41-04-2	0-5V	0-10V
Order Now	7B41-05-1	0-20V	1-5V
Order Now	7B41-05-2	0-20V	0-10V
Order Now	7B41-06-1	+/-20V	0-10V
Order Now	7B41-07-1	0-50V	1-5V
Order Now	7B41-07-2	0-50V	0-10V
Order Now	7B41-08-1	+/-50V	1-5V
Order Now	7B41-08-2	+/-50V	0-10V

7B41 Specifications
Wideband mV/V Isolated Input module (typical @ +25C and +24 Vdc)

Description	Model 7B41
Range¹
Standard Range	+/- 5V to +/- 50V
Custom Ranges	YES
Output Range Options (RL > 2 kΩ)	1-5V or 0-10V (1)
Accuracy²
Initial @25C	0.01% span (0.1% max)
Nonlinearity (BSL)	+/-0.02% max
Input Ofs vs. Temp	0.5uV/C
Zero Suppression vs. Temp	0.002%Vz/C
Span vs. Temp	+/-35ppm/C
Output Ofs vs. Temp	+/-0.001% span
Input Bias Current	+/- 100 pA
Input Resistance
Power On	>1M Ohm
Power Off	>1M Ohm
Overload	>1M Ohm
Output Noise
5MHz Bandwidth	2mV peak
10Hz-100KHz Bandwidth	1mV rms
0.1Hz-10Hz Bandwidth	0.5uV peak
Bandwidth, -3dB (7-pole Butterworth Filter)	10 KHz (2)
Output Rise Time, 10-90% span	40 us (2)
Common-Mode Voltage (CMV)
Input-to-Output and Power Continues	1500 Vrms min
Common Mode Rej. (CMR)	110 dB
Normal Mode Rej. (NMR) 50/60 Hz	100 dB/dec >10 Khz (2)
Input Protection	240 Vrms, +/-35Vdc continuous
Input Transient Protection	ANSI/IEEE C37.90.1-1989
Output Resistance	<1 Ohm
Output Voltage/ Current Limit	+/-12V, +/-14mA
Power Supply
Voltage, Rated Performance	14-35Vdc
Current	20mA max
Sensitivity	+/-0.0001%/%Vs
Mechanical Dimensions	1.663"x2.11"x0.563" (42.24mm x 53.6mm x 14.3mm)
Weight	60 gms
Environmental
Temperature Range, Operating	-40°C to +85°C
Temperature Range, Storage	-40°C to +85°C
Relative Humidity	0 to 90% @ +60°C non-condensing
ESD Sensitivity	IEC 801-2, Level 2
RFI Susceptibility	0.1% span max @ 158,440 MHz, 5W, 3 ft.

Warm-up time required to meet specifications is approximately 10 minutes.
(1) +/- 5V and +/- 10V output ranges are available as custom configurations.
(2) Custom Bandwidths available, Rise and Fall times, NMR frequency will vary accordingly
Specifications subject to change without notice.

7B41 ISOLATED, VOLTAGE OR CURRENT INPUT

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