
MEATEST
M-140 Multifunction Calibrator
Operation manual v46
77
Current converter
The current converter and current amplifier form a separate design block based on a transconductivity converter
with 10
-5
S nominal conversion ratio.
A six-range switched current amplifier connects to the output of the current converter.
Its input is fitted with overload protection and a separate circuit which measures the shift between output voltage
and current in 2 and 20 A current ranges. The output stage is push-pull in B class.
Resistance and capacitance simulator
Resistance and capacitance are simulated using electronic simulator.
The Hi and Lo terminals are calibrator’s output terminals. The stage including U1 operating amplifier converts
voltage to current. U2 is a separation amplifier. R1 to R5 and C1 to C3 are range impedance. DA converter has 0
to +1 and 0 to -1 conversion ration and allows the simulation of resistance and capacitance values different from
the range impedances. The output stage increases the permitted current load of the output.
ATTENTION
The simulator’s output voltage (Hi - Lo terminals) is limited to 8 Vpk.
power stage
input
power stage
DA convertor