Iso-Tech IDM93N Manuel D'instructions page 17

(9) Frequency Counter
Range Resolution Accuracy Sensitivity Min. Input Overload
2K Hz 1 Hz 20 Hz
200m Vrms 600V d.c. or
20K Hz 10 Hz 200 Hz
±(1.0%reading + 3digits)
min. 600V a.c. rms
200K Hz 100 Hz 20K Hz
17