Iso-Tech IDM91E Instruction Manual page 11

(2) AC Volts
Range Resolution
200mV 100 µV
2V
20V 10mV
200V 100mV
600V
Input Impedance : 10MΩ, less than 100pF
Accuracy
1mV
±(1.25%reading + 4digit)
40Hz — 500Hz
1V
10
Over voltage
protection
600V d.c. or 600 V a.c. rms