Page 20 OM024-6 Model 240 Operating Manual
6 Symbols
The following symbols appear on the audiometer or mains adapter:
Definition: Refer to instruction manual (mandatory).
Definition: Type B applied part – an applied part
providing protection against electric shock, particularly
regarding allowable patient leakage current and patient
auxiliary current.
The applied parts are the left & right earphones, bone
vibrator, insert masker, patient response switch and the
associated cables.
Definition: The output from the mains AC adapter is
Direct Current.
Definition: Class II equipment – equipment in which
protection against electric shock does not rely on basic
insulation only, but in which additional safety precautions
such as double insulation or reinforced insulation are
provided, there being no provision for protective earthing
or reliance upon installation conditions.
7 Technical Information
Audiometer
Audiometer type: Type 3 (IEC 60645-1:2001)
Type 3 (ANSI S3.6:2004)
Battery function
Battery voltage range: 4.0 to 6.0V.
Low battery warning: approx 4.4V.
Expected battery life: 6 to 8 hours use from alkaline batteries.
Frequency Modulation
Carrier frequencies: 125Hz to 8kHz as per pure tones
Modulation waveform: Sinusoidal
Rising and falling symmetry: Symmetrical on linear frequency scale
Modulating frequency: 15.625Hz
Frequency deviation: +/-10%