Tonghui TH2840 Series - Deviation and Reference; Limit Setup

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3.4.12 Deviation and reference
3.4.12.1 Deviation mode
Parameter setting attributes: enumerated type.
The deviation test function can make the deviation value (instead of real test value) be directly
displayed on the screen. The deviation value is equivalent to the real test value subtracting the
pre-set reference value. This function brings great convenience to observe variations of component
parameters with temperature, frequency, bias.
The instrument provides two deviation test modes as below:
 Δ (Absolute Deviation mode)
The deviation currently displayed is the difference between the test value of the DUT and the
preset reference value. The formula of calculating ΔABS is as below:
Δ＝Ｘ－Ｙ
Where, X is the test value of DUT
Y is the preset reference value.
 Δ% (Percentage deviation mode)
The deviation currently displayed is the percentage of the difference between the test value of
DUT and the preset reference value divided by the reference value. Its calculating formula is as
below:
Δ%＝(Ｘ－Ｙ）/ Y ×100 [%]
Where, X is the test value of DUT.
Y is the preset reference value.
If the reference value is 0, the test result shows Inf;
3.4.12.2 Deviation reference value
Parameter setting attribute: numeric input type.
It is the reference value used to calculate the deviation of the test result;
Reference value setting method:
1) Regular numerical input;
2) Automatic recording after measurement: Select the measurement function in the corresponding
menu area of the reference, a test will be executed, and the test result will be recorded here as the
parameter value.
3.5 <Limit Setup>
Press the menu key [Setup], and then press the Limit Setup soft key to enter the <Limit Setup> page.
As shown in Figure 3-5-1: