Testboy TV 225, Operating Instructions Manual

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Operation
20 Testboy
®
TV 225
Switching on/off
Switching on: press and hold down the ON/OFF button [7] until you hear a beep.
Switching off: press the ON/OFF button [7]. You will hear a short beep and the display
will go off.
Automatic switch-off
When there is no signal to be measured and if no buttons are pressed, the instrument will
switch off automatically after five minutes.
Display backlight
Press the button with the sun symbol [5] to switch on the display backlight. Press the but-
ton again to switch the backlight off.
Lighting of the measurement location
Press the button with the torch symbol [6] to light up the measurement location. Press
the button again to switch off measurement location lighting.
Reading memory (HOLD)
To save the reading (e.g. if it is difficult to see the display at the measurement location),
press the HOLD button [8]. The symbol "H" appears on the display. The reading is re-
tained until you press the button again.
Voltage/resistance/continuity testing
Connect the red test lead to the "V, Ω, o)))" socket [10] and the black test lead to the
"COM" socket [9].
Use the measurement probes to carry out testing parallel to the voltage source or the re-
sistance. The instrument automatically detects whether DC or AC voltage is present, or
switches to resistance testing.
If the resistance values are lower than 50 Ω (continuity), you will hear a continuous beep.
The reading appears on the main display.
Where DC voltage is detected, "DC" is displayed. The polarity of the measured voltage in
relation to the reference point (black test lead) is also displayed. Negative polarity is indi-
cated by "-".
Where AC voltage is present, "AC" is displayed, and the frequency of the AC voltage is
shown in the auxiliary display.
The order of automatic detection is as follows:
AC voltage → DC voltage → AC, resistance/continuity