
M-140 Multifunction Calibrator
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Operation manual v46
Control sequence when output voltage over 100 V is selected
When output voltage over 100 V is selected, the information section of the display shows the symbol which
informs that a life-threatening voltage will be present at the output terminals. If the output terminals are currently
connected, they will be disconnected when output voltage over 100 V is selected. OUTPUT button must be pressed
to reconnect the output signal to the output terminals. After the OUTPUT button is pressed, an interrupted beep is
sound, OUTPUT LED is lit and the information section of the display shows the symbol notifying the user about
the connection of the dangerous output signal to the output terminals.
Voltage, polarity, frequency, absolute and relative deviation can be set without the outputs being disconnected.
The output terminals are automatically disconnected when changing between AC and DC ranges or when changing
the function mode.
Using AUTOCAL function
To remove the effect of short-term drift and temperature dependency of small DC voltages, AUTOCAL function
can be used. It can only be activated in the calibration mode. “Calibration mode” lists the respective procedure.
Overloading of terminals
If the output terminals are overloaded or short-circuited in the voltage mode, the calibrator disconnects the signal
from the output terminals and reports „Overload U output“ error.
ATTENTION DANGEROUS VOLTAGE
When the calibrator is controlled remotely, it is not possible to disconnect
the output voltage using the buttons located at the front panel!
The calibrator must be first switched to local control mode by pressing the
LOCAL button and then the output terminals can be disconnected or the
mains switch must be switched off !
ATTENTION DANGEROUS VOLTAGE
Never touch the measurement circuit when voltage over 50 V is set and
output terminals are connected!
When working with voltages over 50 V, rules for work with dangerous
voltage must be adhered to.