Fluke PM3082, Руководство по обслуживанию

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6 - 8
PERFORMANCE TEST
6.3.7 Vertical deflection; variable gain control range (continuation of 6.3.6)
This test checks the vertical VARiable gain control.
Settings/procedure:
1 - Apply a square-wave signal of 0.2V to input CH1 and press AUTOSET.
2 - Set CH1 to 50 mV/div and input coupling to DC. Using the CH1 POS control, center the
waveform in the screen.
3 - Select the VARiable mode by simultaneously pressing both AMPL keys. The readout changes
into 50.0 mV/div.
4 - Press the mV key to adjust an input sensitivity of 40.0 mV/div.
Requirements:
Verify that the displayed amplitude is between 4.86 and 5.14 divisions (+/- 2.8%).
Repeat the settings and procedure for CH2. For the PM3094 and PM3084 repeat the same steps for
CH3 and CH4.
6.3.8 Vertical deflection; input coupling (continuation of 6.3.7)
This test verifies the operation of the AC input coupling. Also, the operation of the ground (GND)
function is checked.
Settings/procedure:
1 - Switch the CH1 VARiable mode off by simultaneously pressing both AMPL7VAR keys. The
readout changes to 50 mV.
2 - CH1 sensitivity is 50 mV/div; the vertical deflection is now 4 divisions.
Requirements:
1 - Activate the CH1 GND function and verify that a horizontal line is displayed.
2 - Select the AC input coupling and verify that a 4 divisions square-wave signal is displayed.
Center this signal in the middle of the screen.
3 - Select the DC input coupling and verify that the 4 divisions square-wave signal moves up. This
shift is caused by the signal’s positive dc component: this component is not blocked in DC
coupled mode.
Repeat the settings and procedure for CH2, CH3, and CH4. In the PM3092 and PM3082, the test of
the GND function is skipped for CH3 and CH4.
6.3.9 Vertical cursor accuracy (continuation of 6.3.8.)
This test verifies the accuracy of the voltage cursors
Settings/procedure:
1 - Change the generator output voltage to 0.1V.
2 - Apply this voltage to CH1.
3 - Switch CH1 to ON and the other channels off.
4 - Select DC coupled input and 20 mV/div for CH1.
5 - Select CH1 as trigger source (TRIG 1).
6 - Center the 5 div square-wave (on the dotted horizontal lines of the graticule) with the POS rotary.
7 - Press the CURSORS menukey.
8 - Select ’on’ and volt cursors (=) in the CURSORS menu.
9 - Select A V in the READOUT menu.
Requirements:
Position the cursor lines exactly on top and bottom of the signal using the TRACK and A controls.
Check for a cursor readout between 98.4 and 101.6 mV.