As an automatic test and control system composed of the computer, printer, high precision digital multimeter, the TZ SC-03 low potential scanner/controller, signal generator (optional) and the GP-IB(IEEE-488) interface, the ZRJ-03 intelligent thermal meter verification system is a new-type intelligent measurement standard device with the integration of the computer technology, micro-electrical measurement technology and the automatic test technology used for the automatic verification of the working thermocouple and resistance thermometer. With the appropriate software, it can verify the secondary temperature meter and expansion thermometer. And the S standard thermocouple verification (needs to be purchased separately) software is specially designed for this system. The verification procedure and result is in accordance with China’s current relevant measurement and verification regulation. The system has advantages of the advanced design, reasonable structure, complete software function, convenient operation, beautiful interface, accurate and reliable transfer of measurement value, high anti-interference ability and flexible configuration. The verification software and core hardware of the system are both independently developed by our company.
1.1 Main Technical Indicators
Parasitic EMF of scanning switch
Range of reference junction compensation of thermocouple
Control ability of thermocouple verification furnace
Temperature control stability
Better than 0.2℃/min (verification furnace)
1.2 Part of Implemented Verification Regulation and Specification
Code of Regulation
Name of Regulation
Verification Regulation of Working Noble Metal Thermocouple
Verification Regulation of Working Platinum-10% Rhodium/Platinum and Platinum-13% Rhodium/Platinum Thermocouple with Short Length
Verification Regulation of Working Base Metal Thermocouple
Verification Regulation of Industrial Platinum Copper Resistance Thermometers
Calibration Specification for Auto-measuring System of Thermocouples and Resistance Thermometers
1.3 Characteristics of System
Characteristics of TZ.SC-03 Low Potential Scanner/Controller
The main function of the TZ.SC-03 low potential scanner/controller is to provide the program-controlled low potential multi-channel switch, the temperature control channel of the thermostat (the verification furnace and oil bath) and the temperature measurement channel of the reference junction.
n Characteristics of Scanner
l Electromechanical integration structure. It not only absorbs the advantages of the traditional low potential switch but also realizes the programmed control and remote control functions.
l Low parasitic EMF. The large-area silver covered materials are used for the switch substrate and the parasitic EMF is guaranteed as not exceeding ±0.2μV for long time.
l The contact resistance of the switch is low and has high consistence.
l It has special low potential terminal block.
l The connecting wire compatible to the thermocouple and resistance thermometer. The external lead resistance is completely eliminated by the use of the 4-wire resistance measurement method
n Characteristics of Controller
l It has its own actuator. The large power solid state relay (SSR) with the optoelectrical isolation function is used to control the thermocouple verification furnace (or oil bath). The small volume, weight and heating value and simple structure greatly improves its working reliability.
l High precision AC zero crossing trigger. There is no high order harmonic. The relative resolution of the power output is better than 1/1024.
n Characteristics of Temperature Measurement of Reference Junction
l When verifying the base metal thermocouple (such as K, N, J, E types), the function of “reference junction temperature compensation” is allowed to be selected. Three methods of dealing of the reference junction can be selected.
1.3.2 Functions and Characteristics of System
n Complete Software Functions
l The verification system software can be run under the operating system including Windows 2000, Windows XP and Windows98 etc.
l The relevant parameters during the verification can be indicated in “the indicating meters” of “the simulation meter panel”. Being easy to use, it has the characteristics of the industrial control software.
l During the temperature control of the thermostat, the temperature curve (the temperature-time relationship curve) is automatically drawn. The power curve, rate in change of power curve can be observed simultaneously and can be enlarged or reduced.
l The verification data and record curve can be stored as files on the hard disk and into the database at the same time. It can be searched, calculated and printed at any time.
l It has the mode of the simulation running. The verification procedure can be simulated at high, medium and low speed on the computer without the external device.
l Power failure protection function. If there is sudden power failure or artificial quitting of the program during the verification, when the verification program is restarted, it will prompt whether to continue or restart verification. To continue verification can save time and improve efficiency.
n Main Characteristics of Verification Function
l The thermocouple of types of S, R, B, K, N, J, E, T, EA-2, short S and short R (ClassⅠ, ClassⅡ T Class Ⅲ) can be verified. For the verification temperature points, the default points can be automatically provided by the program, and they can also be set by customers. The range of setting is 1-8 verification points. When verifying the thermocouple at below 300℃, the grade 2 standard platinum resistance thermometer can be used to replace the grade 2 standard glass thermometer to realize the automatic verification.
l The integrated temperature measurement transmitter of 0-10mA, 4-20mA and 1-5V output can be verified.
l The Pt10, Pt100, Cu50 and Cu100 resistance thermometer (class A and B) including 2-wire, 3-wire and 4-wire resistance thermometer can be verified.
l The balanced, moving coil and digital temperature meter can be verified.
l Supports the choosing of the thermostat including up to 5 medium temperature thermocouple verification furnaces of different models, 1 high temperature verification furnace and 1 oil bath. One group of PID parameters can be set every 100℃ at the range of 300℃-1100℃，800℃-1600℃，and 100℃-300℃ to ensure the optimum temperature control results of each thermostat at different temperature zones.
l The verification of the resistance thermometer, low temperature thermocouple and low temperature integrated temperature transmitter can be performed in groups. The maximum 10 groups can be verified for one batch. (The maximum number in each group is related with the model of the supporting scanner, e.g. 6 for TZ.SC-03, 10 for TZ.SC-03B.) During verification, any group can be tested at any set verification point according to the situation to effectively improve the efficiency when there is too much verification work.
l The record table and certificate of the “verification” or “calibration” can be chosen. The standard or custom format can be chosen for the verification or calibration certificates.
l When the verification work is finished and the verification has not been quitted and the verification certificate is indicated, the verification conclusion can be adjusted for one time according to the verification results. For example, the verification result notice of “not in accordance with the working class Ⅰ” can be adjusted to the verification certificate of “in accordance with the working class Ⅱ” if the class Ⅱ precision requirements are met.