The intelligent digital display instrument adopts a dedicated integrated instrument chip, and the measurement input and transmission output adopt digital calibration and self calibration technology, which ensures stable measurement and eliminates measurement errors caused by temperature drift and time drift. The instrument adopts surface mount technology and is designed with multiple protection and isolation measures. It has strong resistance and high reliability through EMC electromagnetic compatibility, and has a high cost-effectiveness.

Intelligent digital display instruments have multi type input programmable functions. One instrument can be matched with different input signals (thermocouple/thermistor/linear voltage/linear current/linear resistance, etc.), and the display range, alarm control, etc. can be set by the user on site. It can be used in conjunction with various sensors and transmitters to achieve measurement, display, adjustment, alarm control, data acquisition and recording of physical quantities such as temperature, pressure, liquid level, capacity, force, etc. Its scope of application is very wide.

The intelligent digital display instrument displays the measured value (PV) and set value (SV) with dual row or single row four position LED, and simulates the percentage of measured value with single or dual color light column. It also has zero and full correction, cold end compensation, digital filtering, communication interface, four types of alarm, and can be equipped with 1-4 relay alarm outputs. It can also be equipped with transmission output or standard communication interface (RS485 or RS232C) output. Range: Temperature measurement ranges from 0 to 80 ℃; Humidity measurement ranges from 0 to RH, corresponding to an analog output of 4 to 20mA. Accuracy level: relative humidity range of 5% to 98% RH, compensation temperature range: 40 ℃, 2% RH; 50℃,3%RH; 80℃,5%RH; Temperature: 0-50 ℃ with an accuracy of 0.5%; The accuracy is 1% at 50-80 ℃. Temperature sensor applicable temperature range: -40~100 ℃ Load capacity: constant current load of 100-500 Ω (4-20mA), stability: humidity measurement drift of 1%~2% RH for 3 years under normal and low temperature conditions, humidity measurement drift of 1%~2% RH per year under high temperature and high humidity (40 ℃, above 80% RH), sensor non failure life of 5-8 years, response time: 1 second for humidity rise, 10 seconds~2 minutes for dehumidification, and 5 seconds for temperature rise.

Detailed Explanation on Transmission Output

Single channel instrument Out=0B0D

B: Transmission of output status when input fault occurs, D output signal type

Dual channel instrument Out=ABCD

B: When there is an input fault in the channel, the output status is transmitted

D channel output signal type

A: When there is an input fault in the second channel, the output status is transmitted,

C Second channel output signal type

A. Set the transmission output status for faults such as line input disconnection and exceeding the upper limit; A. B=0 follows the output. At this point, the output completely follows the input changes, but does not exceed 10% of the upper limit;

A. B=1 Over range output. When there is an input fault, the over range output is 105% of the original output upper limit,

When the output is 4-20mA, the over range is 21mA. The instrument alarm is set for 1~, and the instrument alarm point and alarm mode are set through the parameter setting menu. SP1, SP2, SP3, SP4 set alarm points, P1h, P2h, P3h, P4h set alarm return values. P1c, P2c, P3c, P4c are set with alarm formulas, and the alarm value setting must follow the range lower limit ≤ alarm lower limit ≤ alarm lower limit ≤ alarm upper limit ≤ alarm upper limit ≤ range upper limit. 1. The setting of alarm hysteresis. When the measurement signal fluctuates near the alarm point, the instrument continuously exits the alarm state, causing the output contacts to frequently jump, triggering an alarm and causing external interlocking devices to malfunction. This series of intelligent digital display devices has a hysteresis setting function, which can avoid this situation. The SP2 is 50. P2h is 2. P2c is 30.

At 5V and 0-5V, the over range output is 5.25V;

A. B=2 Under range output. When there is an input fault, the under range output is subtracted from the original output lower limit value

5% of the upper limit value, such as under load when outputting 4-20mA

Cheng is 3mA, and the under range output is 0.75V when it is 1-5V; C. D sets the type of transmission output signal;

C、D=00～10mA； C、D=14～20mA； C、D=20～20mA； C、D=31～

5V; C, D=40~5V;

Calibration of Intelligent Digital Instruments

Warning: The instrument has been strictly calibrated with precision instruments before leaving the factory. Generally, do not press any buttons to perform this operation, otherwise it will affect the accuracy of the instrument's operation and even cause instability. This operation can only be carried out when the instrument has been used for many years, and due to aging of parts, the indication value has irreversible drift and exceeds the accuracy range, or when the input signal type of the standard signal type instrument has been changed and the standard instrument meets the accuracy requirements of the verification specification. When the sound and light alarm function is effective, mute and start the mute time, and switch to the display mode of the analog bar when the single analog bar mode is pressed. Press the display mode switch key for the digital display section, and the manual/automatic key A/M for instruments with manual/automatic switching function. Press this key to manually operate the instrument. 2. The instrument is in manual operation mode. The SET key has no effect. The displacement key has no effect. The PID control quantity of the decrease key is reduced. Key PID control quantity. Press the manual/automatic key A/M to exit the manual mode and automatic operation mode. 3. Under the parameter setting mode. After setting the parameter setting mode with the SET key, the parameter modification confirmation key is used to control the next parameter setting of the instrument. When the end prompt appears after setting the next parameter, pressing this key again will exit the parameter setting mode, or pressing it together with the A/M key after setting any parameter will exit the parameter setting mode.

1. Set SEL to 159, press the SET key to enter the calibration menu, press the SET key according to the instructions in [Table 6], and use the MAN key to select the type of menu that needs to be calibrated.

2. According to the required calibration signal category, connect a signal source of no less than 0.05 level to the corresponding wiring terminal.

3. After the signal stabilizes, press the △ key once to start automatic calibration. When the displayed value stabilizes or the error is within 0.05%, press the SET key to automatically save the calibration data, and the displayed value is calibrated to the standard value of the current signal type. Afterwards, the signal source size can be adjusted to observe whether the displayed value synchronizes and changes linearly with the signal source size, in order to determine whether the calibration of the standard value is correct.

If calibration cannot be repeated, step 3 should be checked and the corresponding wiring and calibration steps should be checked. If calibration is required, press the SET button to access the menu for other calibration types and repeat step 2.

Note:

The above steps apply to the calibration of menu types E0, E2, E3, E5, E7, and E9. For the calibration of E1 menu, which is the cold end temperature, please note that after pressing the △ key once in step 3 to start calibration, wait for a few seconds, and the current temperature will start to be automatically detected and displayed. At this time, the room temperature value needs to be manually read from the standard thermometer. If there is an error in the value displayed on the instrument, manually enter the standard value, and then press the SET key to confirm.