MODEL 110 AUTORANGING DIGITAL MULTIMETER
4.0Control Functions:
4.1Function Selector Rotary Switch
The rotary switch turns power on to the instrument and selects the function to be measured. The functions available and their specifications are detailed in Section 2.0.
4.2Range Selection
In all functions except 
(Diode Test) and A (AC or DC Current), the instrument powers on in the Autoranging mode and the AUTO symbol appears in the display. To select a range manually, press the ‘Range’ button. The Manual Range symbol will appear in the display, and the instrument will then be locked in the range selected. When in the Manual mode, each successive press of the ‘Range’ button increases the measurement range. Range selection loops back to the lowest range when advanced from the highest range. To exit the Manual mode, press and hold the ‘Range’ button for one second or rotate the Function Selector switch to a different measurement function, and the instrument returns to the Autoranging mode.
4.3Relative Operation
Pressing the UREL button zeroes the display and internally stores the present reading as a reference for subsequent measurements. The main display now shows the difference between the stored value and the new reading. Press and hold the UREL for one second to exit the Relative mode.
4.4MAX/MIN Operation
Press the MAX MIN button to enter the MAX/MIN mode. In this mode, both the maximum and minimum values are simultaneously retained in memory and updated with every new data sample. The instrument first enters the MAX mode, and the MAX symbol and value are both displayed. Pressing MAX MIN again advances the display to the MIN symbol and value. The next press of the MAX MIN button will cause both the MAX and MIN symbols to flash. This indicates that the maximum and minimum values have been updated in memory and the displayed
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MODEL 110 AUTORANGING DIGITAL MULTIMETER
5.6 Diode Tests
WARNING!
Before making any
1. | Connect the red test lead to the ‘ | ’ |
| jack and the black test lead to the ‘COM’ | |
| jack. |
|
2. | Set the Function Selector switch to the | |
| range. |
|
3. | Remove power from the circuit being | |
| tested and discharge all capacitors in | |
| the circuit. |
|
4. | Connect the red test lead to the anode | |
| side and the black test lead to the | |
| cathode side of the diode being tested. |
|
5. | Read the Forward Voltage (Vf) on the | |
| instrument display. |
|
Note: If the polarity of the test leads is reversed, the display will | ||
read ‘OL’. This can be used to determine the anode and | ||
cathode terminals of a diode. |
| |
5.7 Frequency Measurements |
| |
1. | Connect the red test lead to the ‘Hz’ jack | |
| and the black test lead to the ‘COM’ jack. |
|
2. | Set the Function Selector switch to the | |
| Hz range. |
|
3. | Connect the test leads in parallel with | |
| the circuit being measured. |
|
4. | Read the frequency on the instrument | |
| display. |
|
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