 |
Laureate™ Calibration Software
For Thermocouple / RTD panel meters, plus DC, strain
& load cell meters used in ratiometric / bridge mode.
First calibration software screen for
Laureate digital panel meters.
Laureate DPM Calibration Fundamentals
As shipped by Laurel Electronics, all ranges
of Laureate digital panel meters are fully
calibrated, with calibration factors stored in EEPROM. This allows different
ranges to be selected via plug-in jumpers, with no need to recalibrate the
meter for each new range. The 0-200 mV scale serves as the reference scale. All other scales
apply multipliers to this scale.
This calibration page applies to the
following Laureate meters:
- Thermocouple / RTD meter / pyrometer
- DC / strain meter used in ratiometric /
bridge mode
- Load Cell meter used in ratiometric /
bridge mode
Calibration of these meters requires
a temporary serial data connection to a PC and use of special Laureate
Calibration software, which is downloadable at no charge by clicking on the
links below. Calibration entails the application of a known
reference signal to each scale and the automatic calculation of a multiplier
so that the reading corresponds to that signal. In case of a DC meter, the 200.00 mV
scale is calibrated first because it servers as a multiplier for the other
scales. When a 200.00 mV signal is applied, the meter will actually read
80000 during calibration. The reading is multiplied by a factor of 4 to
assure a more accurate calibration.
Computer-assisted calibration can be manual
or automatic. In manual calibration, the computer screen prompts the
operator step by step on which jumpers to set and reference signals to
apply, and then to press the Enter key on the computer keyboard. In automatic calibration, the computer controls both the Laureate
and the calibrator; however, a person still has
to position jumpers to select the various ranges.
|
Required Hardware &
Software
|
| 1. |
A Laureate DPM with an RS-232 or RS-485
serial communications board. If required, such a board can be installed
temporarily in the meter for the calibration, then be removed. |
| 2. |
A PC-compatible computer operating either
under MS DOS or Windows, with an available COM2 port. |
| 3. |
|
| 4. |
A certified external calibrator for
reference voltage, current or time base. In addition, an ice point cell
is required for thermocouple calibration. Automatic calibration of
meters with an analog input requires a Fluke Model 5100 calibrator or
equivalent with an IEEE-488 connection to the computer. |
| 5. |
Laureate calibration software, which can be
downloaded at no charge by clicking on the links below: |
| |
For temperature meter (119 kB) |
| |
For a load cell panel meter (124 kB) |
| |
Auxiliary data file for load cell meter (17
bytes). |
| |
For all ranges of a DC
meter (136 kB). |
| |
Auxiliary data file for DC meter used in
ratiometric mode for pot follower or strain gauge applications (17
bytes). |
Absolute Range Calibration
for Temperature, DC or Load
Connect the Laureate to the calibrator and computer,
double-click on the appropriate executable file (caldc4q.exe or
caltc4q.exe), and follow the prompts on the computer
screen. Following calibration, all calibration factors will be stored in EEPROM.
|
Ratiometric Calibration for
Load Cell or DC Ratio
|
| 1. |
Calibrate the absolute 200 mV range for the
DC signal conditioner or the absolute 250 mV range for the load cell
signal conditioner. |
| 2. |
Place the auxiliary file LOADCEL.FIL is in the same directory as
CALLC4Q.EXE (load cell meter), or the auxiliary file DCRATIO.FIL in the
same directory as CALDC4Q.EXE (DC meter used in strain or ratiometric
mode). |
| 3. |
Connect the Laureate to the calibrator and
computer, double-click on the appropriate executable file (CALLDC4Q.EXE
OR CALLC4Q.EXE), and follow the prompts. Your first step will be to
perform a calibration of any DC ranges that will be used for ratiometric
operation. |
| 4. |
Connect the calibrator via a voltage divider
circuit as illustrated below, using two 5 kΩ resistors and one 175 Ω
resistor (1% accuracy).
|
| 5. |
Set the DC signal conditioner to the 200
mVdc range or the load cell signal conditioner to the 250 mV DC range.
Set scale to 1 and zero offset to 0. Set the calibrator output to 10.000 V.
Read the voltage displayed on the meter for the signal applied across pins 3 and 4. |
| 6. |
Make the M2 selection on the computer
screen, and follow the prompts for ratiometric calibration. As part of
this process, you will
need to enter the voltage measured in step 5. |
| 7. |
Following ratiometric calibration, all
correction factors will be stored in EEPROM for 0.01% accuracy.
|
|
|
|
