Introduction
Welcome to Lives International – leading supplier of thermal validation equipment for over 18 years.
Lives International supplies both thermocouple based systems and wireless data loggers… nevertheless, there are more competitive advantages attached to Data Loggers that make them more attractive in terms of time savings and decreased downtime of production equipment.
In this video we show the simplicity and huge time savings of using data loggers rather than thermocouples for shelf mapping a freeze dryer.
It is important to understand why Data Loggers are such an interesting tool and how they work compared to Thermocouples.
As per industry good practice, 5 sensors per shelf are being used to cover the 4 corners and the center of each shelf. We are using a 16 shelves freeze dryer that requires a total of 80 temperature sensors.
The first obvious difference between the two systems is the hardware and man power needed… while two XpertVal-60 TC Systems are needed and 2 validation engineers for the TC System, only one engineer and 80 loggers are required for the data loggers system.
Step 1 - Module Connection
Thermocouples
In terms of installing the systems, the TC System requires the thermocouples to be connected to the modules. As each module may accomodate 20 thermocouples, 4 modules are needed to connect 80 thermocouples.Each thermocouple also needs to be labeled and all together these tasks take roughly 30 minutes for each module.
Data Loggers
This step is not needed for data loggers, as each data logger has the sensor attached and calibrated together wiith the electronics from factory with ID shown on the logger and in the software.
Total time to connect the thermmocouples: 2 hours vs 0 for data loggers. Obvious winner: data loggers!
Thermocouple Based Systems
XpertLog® Data Loggers
CONNECT TC’S
2 hours
0 hours
TOTAL TIME
2 hours
0 hours
Step 2 - Calibration
While the thermocouple is made of 2 different conductors welded on one side and connected to a module on the other side, generating a very low voltage corresponding to the temperature measured, thus very poor accuracy and stability, XpertLog Data Loggers use 4 wires PT-100 which provides state of the art accuracy and stability. As a consequence, the thermocouples MUST be calibrated before and verified after each test or succession of tests while the Data Loggers MAY be verified to prove they are within specs without needing to re-calibrate them. These accuracy measurements before and after the test is a safety feature to validate the test, not to mention to comply with the current regulations for autoclave validations.
Thermocouples
Data Loggers
Time needed to calibrate 80 thermocouples: 8 hours vs. 4 hours to verify the 80 data loggers. Again, we have a winner: Data loggers!
Thermocouple Based Systems
XpertLog® Data Loggers
CONNECT TC’S
2 hours
0 hours
CALIBRATION
8 hours
4 hours
TOTAL TIME
10 hours
4 hours
Step 3 - Pass the sensors inside
Oncee the calibration/verification of the sensors has been performed, the sensors have to be placed insidee the equipment to be validated. Several feedthrough are required to pass all the thermocouples inside the equipment.
Data loggers are easily placed on the selves without needing a feedthrough – using a special deviced called shelf mapping cap – remember they send the signal out from the equipment using radio frequency signal instead of wires!
Thermocouples
Data Loggers
The 2 hours needed to pass the thermocouples inside the freeze dryer are once again skipped when using data loggers.
Thermocouple Based Systems
XpertLog® Data Loggers
CONNECT TC’S
2 hours
0 hours
CALIBRATION
8 hours
4 hours
PASS TC’S INSIDE
2 hours
0 hours
TOTAL TIME
12 hours
4 hours
Step 4 - Place the sensors on the shelves
A time consuming operation is placing the temperature sensors on the shelves as previously described. The loggers are placed in a device called lyo-puck are pushed to the designated location – a 1.5 hours operation compared to a lenghty 6 hours to place 80 thermocouples!
Thermocouples
Data Loggers
Thermocouple Based Systems
XpertLog® Data Loggers
CONNECT TC’S
2 hours
0 hours
CALIBRATION
8 hours
4 hours
PASS TC’S INSIDE
2 hours
4 hours
PLACING THE SENSORS
2 hours
0 hours
TOTAL TIME
14 hours
4 hours
So far, a total of 5.5 hours for Data Loggers. vs 18 hours for thermocouples – gues who the winner is again?!
Not withstanding the time required to handle the thermocouples during the mapping, even bigger challenges are to be anticipated when using them – the wires may be accidentally cut, stripped, twisted – which increase the total time and cost of the mapping.
Start the Freze-Dryer Cycle
The freeze dryer cycle starts now; the signal is transmitted through radio frequency from Lives Data Loggers to the receiver which is USB connected to a computer and processed by the 21 CFR Part 11 Compliant software XpertLog®
Step 6 - post-test verification
A last step in this process is running the post-test verification. This is mandatory for autoclaves and recommended by the good industry practice for the other types of equipment. It proves that the sensors used for the mapping are within the specifications before and after the test.
Compare five hours post-test verification for thermocouples with two hours for data loggers.
Total time to run the freeze dryer shelves mapping using thermocouples: 25 hours and two validation engineers
Total time to run the freeze dryel shelves mapping using Data Loggers: 8 hours and only one validation engineer.
