Measurement Amplifier U (115 V, 50/60 Hz)

Description
Recommended
Experiments

Measurement amplifier U amplifies low-amplitude measurement signals from low-resistance signal sources for measurement with any chosen voltmeter or oscilloscope. By using an external shunt resistor it is also possible to measure small currents. Offset voltages can be compensated using coarse and fine offset adjustment knobs. Amplification (gain) can be selected in ranges from 0 to 5 powers of ten. High-frequency noise or other interference signals are filtered out by means of a low-pass filter with step-wise selectable time constants between 0 and 3 seconds. The output voltage has the same sign as the input voltage.

Input resistance:                             10 kohm
Output resistance:                          300 ohm
Offset voltage drift:                          < 2 μV/K (after 15 mins.
operation approx.)
Gain factors:                                    10⁰; 10¹; 10²; 10³; 10⁴; 10⁵
Tolerance for gain factors:            < 2.5 %
Input voltage:                                   max. ±12 V
(overload protected for
brief transients up to 100 V)
Output voltage:                                0 … ±12 V
(short-circuit protected)
Power supply (via
plug-in supply provided):               12 V AC
Ambient temperature:                     5°C ... 23°C … 40°C
Storage temperature:                      -20 … 70°C
Relative humidity:                           <85%
no condensation
Operational alignment:                  Horizontal
Contamination level:                      2
Protection class:                              IP20
Dimensions:                                    170x105x50 mm³ approx.
Weight:                                             335 g approx.

Measurement and frequency ranges (relative to 1 V output voltage)

Gain	Input voltage	Current through R_Shunt = 100 ohm	Frequency
10⁰	1 V	10 mA	0 … 25 kHz
10¹	100 mV	1 mA	0 … 25 kHz
10²	10 mV	100 µA	0 … 25 kHz
10³	1 mV	10 µA	0 … 20 kHz
10⁴	100 µV	1 µA	0 … 7 kHz
10⁵	10 µV	100 nA	0 … 7 kHz

Cut-off frequency for switchable low-pass filter

Time constant	Cut-off frequency
0.0 s	See Table 1
0.1 s	1.6 Hz
0.3 s	0.5 Hz
1.0 s	0.16 Hz
3.0 s	0.05 Hz