Ametek 7280 Instruction Manual page 118

Chapter 5, FRONT PANEL OPERATION
5-72
LOG RATIO1
where X1 output is the X1 channel output as a percentage of the full-scale
sensitivity and ADC 1 is the voltage applied to the ADC1 input connector on the
rear panel expressed in volts. Hence, for example, if the instrument were
measuring a 100 mV signal when set to the 500 mV sensitivity setting, the X1
channel output were maximized and a 1 V signal were applied to the ADC1
input, then the value of LOG RATIO1 would be:-
LOG RATIO1
LOG RATIO1
The relationship between the voltage at the CH1/CH2 connector and the
LOG RATIO1 value is defined as follows:-
LOG RATIO1
+2.000
0
-3.000
Note: If RATIO1 < 0 then LOG RATIO1 = -3.000
EQUATION #1
When set to EQUATION #1 the corresponding CH1/CH2 connector on the rear
panel will output a voltage related to Equation 1, which is defined using the
Output Equations menu (see section 5.3.08), as follows:-
EQUATION #1
+10000
0
-10000
EQUATION #2
When set to EQUATION #2 the corresponding CH1/CH2 connector on the rear
panel will output a voltage related to Equation 2, which is defined using the User
Equation 2 menu (see section 5.3.08), as follows:-
EQUATION #2
+10000
0
-10000
10 X1 output
log
10
ADC1 input
0.1
10
0.5
log
10
1.000
= 0.301
CH1/2 Voltage
2.000 V
0.0 V
-3.000 V
CH1/2 Voltage
10.0 V
0.0 V
-10.0 V
CH1/2 Voltage
10.0 V
0.0 V
-10.0 V