The JOFRA DTI-1000 with an
STS-probe is a fully traceable thermometer recommended
as the reference instrument to verify the true
temperature in any type of temperature calibrator,
liquid bath, or dry-block calibrator.
Use the JOFRA DTI-1000 and the STS probes as your
working temperature reference in any calibration
application or use the set-up directly in custody
transfer applications where high accuracy (low
uncertainty) means money.
The superior specifications combined with a long history
of reliability and low drift have made the JOFRA
DTI-1000 and the STS probes the working standard in many
national laboratories worldwide.
True Ohm Measurement
The DTI-1000 has been designed to employ state-of-the-art DC measuring techniques in combination with powerful microprocessor technology. To achieve high accuracy, the measuring principle used by the DTI-1000 is True Ohm Measurement thus eliminating the EMF from cables, sockets, and sensors.
True Ohm Measurement is a proven method to achieve accurate compensation for errors induced by thermal effects.
The resistance is measured through the 4-wire system at 1 mA, after which the instrument takes a reading without any applied current; this second reading is the "error EMF".
Reference resistors
To minimize the effect of any drift caused by ambient temperature, humidity and /or aging, the DTI series is designed with built-in high precision and extremely stable reference resistors. This technique minimizes drift.
Linearity
To obtain high accuracy, it is necessary to know the characteristics of the Pt100 sensor to be used with the DTI-1000 e.g. one of the JOFRA STS probes.
The DTI-1000 provides 3 different linearity setups:
1. Certified data pairs of ohm and reference temperature. Use JOFRACAL for calculating and downloading of individual coefficients from a certified sensor e.g. a STS JOFRA probe based on "best curve fit"
2. Coefficients, according to IEC 751 (Callender van Dusen) coefficients according to ITS-90
3. Coefficients according to ITS-90
Conversion to temperature
DTI-1000 will accept Callendar van Dusen coefficients R0, A, B and C or ITS-90 coefficients for converting resistance to temperature. If you do not have these coefficients available from the certificate for the sensor, but have measurement data (temperature and resistance), JOFRACAL can help you calculate the coefficients required.
Combining a DTI-1000 and a STS reference sensor with the use of ITS-90 coefficients ensures the best overall accuracy.
JOFRACAL calibration software
The RS232 serial data communication interface allows the DTI-1000 to be serially connected to a personal computer for data storage and reporting. The JOFRACAL software package is included as a standard accessory. The software is menu-driven and easy to use:
- Storage of all sensor coefficients. Quick downloading to the DTI-1000 through the software. Facilitates the easy use of multiple sensors for various applications.
- Complete software controlled calibration procedure, which saves time.
STS Reference probes
To get an ideal reference system JOFRA offers a range of reference probes.
All sensors are supplied with an accredited and traceable certificate from National Accredited Laboratory, stating the sensor coefficients.When using JOFRA STS reference probes together with the DTI-1000, the system accuracy will typically be: ±0.030°C (0.054°F) |
