Fluke 9190A - Uniformity Alignment 2 Nd Iteration; Uniformity Alignment 3 Rd Iteration

9190A
Operators Manual
4-10
8. Enter the New
GRAD 1
calibration parameter into the UUT from the front panel: MENU
> SYSTEM MENU > CALIB > CAL POINTS
or send the New
GRAD 1
calibration
parameter to the UUT with these serial commands:
SYST:PASS:CEN <password>
SOUR:SENS:CAL:GRAD1 <New_GRAD 1>
9. Let the UUT soak at the -90 °C SETPOINT for 45 minutes after the change to the
New
GRAD 1
parameter.
Uniformity Alignment 2nd Iteration
Perform the 2
nd
uniformity alignment as follows:
1. With the UUT still at -90 °C from the previous Uniformity Alignment 1
st
Iteration
procedure, measure the ACTUAL gradient, which is the temperature of the secondary
PRT (30 mm probe) minus the temperature of the primary PRT (0 mm probe). Take
the average of 40 samples for each of the probes. Calculate as follows:
ACTUAL grad = T
30
- T
0
2. Query the UUT gradient sensor reading with this serial command:
SOUR:SENS:GRAD:DATA?
3. Repeat this 40 times to get an average of the gradient sensor reading. This value is
called “UUT grad”. Calculate the Error with this formula:
ERROR
1
= UUT grad – ACTUAL grad
4. If the magnitude of ERROR
1
is less than 0.012, skip to the next Gradient calibration
temperature and repeat the Uniformity Alignment 1
st
Iteration procedure.
5. Query the UUT GRAD 1 calibration parameter with this command:
SOUR:SENS:CAL:GRAD1?
6. Grad 1 is associated with UUT block temperature -90 °C. Calculate the new Grad 1
calibration parameter as follows:
New
GRAD 1
= GRAD 1 – ERROR
1
7. Enter the New
GRAD 1
calibration parameter into the UUT from the front panel: MENU
> SYSTEM MENU > CALIB > CAL POINTS
or send the New
GRAD 1
calibration
parameter to the UUT with these serial commands:
SYST:PASS:CEN <password>
SOUR:SENS:CAL:GRAD1 <New_GRAD 1>
8. Let the UUT soak at the -90 °C SETPOINT for 45 minutes after the change to the
New
GRAD 1
parameter.
Uniformity Alignment 3rd Iteration
Perform the 3
rd
uniformity alignment as follows:
1. With the UUT still at -90 °C from the previous Uniformity Alignment 2
nd
Iteration
procedure, measure the ACTUAL gradient, which is the temperature of the secondary
PRT (30 mm probe) minus the temperature of the primary PRT (0 mm probe. Take
the average of 40 samples for each of the probes. Calculate as follows:
ACTUAL grad = T
30
- T
0
2. Query the UUT gradient sensor reading with this serial command: