WECON PLC Extend Module LX3V-4TC
8Pages

Wecon Technology Co.Ltd., SITE: http://en.we-con.com.cn Technical Support: liux@we-con.com.cn Skype: fcwkkj PHONE: 86-591-87868869

The LX3V-4TC analog block amplifies the signal from four thermocouple sensors (Type K or J) and converts the data into 16 bit reading's stored in the main unit. Both Centigrade (°C) and Fahrenheit(°F) can be Reading resolution is 0.4°C/0.72°F of Type Kand 0.3°C/0.54°F of Type J. The LX3V-4TC can connected to the LX3V series Programmable Logic Controllers (PLC). All data transfers and parameter settings are adjusted via software control of the LX3V-4TC; by use of the TO/FROM applied instructions in the PLC. LX3V-4TC consume 5V voltage from LX3V main unit or active extension unit,90mA current...

The compensating cables that can be used for connecting with the thermocouple are the following. Type K: KX-G, KX-GS, KX-H, KX-HS,WX-G,WX-H,VX-G For every 10Q of line resistance, the compensating cable will indicate a temperature 0.12°C higher than Check the line resistance before using. Long compensating cables are more prone to noise interference, therefore a short (less than 100m) compensating cable is recommended. Unused channels should have a wire link connected between the + and - terminals to prevent an errors being detected on that channel. Extension cable "k!:lf there is excessive...

Current input Current input Note: Preset ranges are selected by an appropriate setting in buffer memory of the analog block. Current/Voltage input selection must match the correct input terminal connections. The LX3V-4TC communicates with the PLC via buffer memories. All non reserved BFMs can be read by the PLC using the FROM instruction. BFM's (buffer memories) marked with an "*" can be written to, the special function block using the TO (1) Buffer Memory BFM #0: Thermocouple Type K or J selection mode BFM #0 is used to select Type K or J thermocouples for each channel. Each digit of a 4...

(1) A/D conversion time is 240ms per channel. When “3" (unused) is set for a channel, A/D conversion is not executed for that channel, therefore, the total conversion time is decreased. In the above example,the conversion time is as follows: 240ms (conversion time per channel) × 2channels (number of channels used) = 480ms (total conversion time) (2) Buffer Memory BFMs #1 to #4: Number of temperature readings to be averaged When the number of temperature readings to be averaged is specified for BFM’s #1 to #4, the averaged data is stored in BFMs #5 to #8 (°C) and #13 to #16 (°F). Only the...

5. System Block diagram data status Power Source Analog Input Cyclic switching In the program shown below, the LX3V-4TC occupies the position of special block number 2 (that is the third closest block to the PLC). A Type K thermocouple is used on CH1 and a Type J on CH2. CH3 and CH4 are not used. The averaging count is four. The averaged values in degrees C of input channels CH1 and CH2 are stored respectively in data registers DO and D1. Specify the type of thermocouples. Identification code i.e. When identification code is K2030, M1 This initial step checks that the special function block...

Number of samples is changed to four on both CH1 and Transfer the averaged temperature value in °C to the data registers. This step is the actual reading of the LX3V-4TC input channels. It is essentially the only program step which is needed. The "TO" instruction in this example, sets the input channels, CH1 and CH2, to take the average reading of four samples. The "FROM" instruction reads the average temperatures (BFM #5 and #6) for input channels CH1 and CH2 of the LX3V-4TC. If direct temperature readings are required BFM #9 and #10 should be read instead, block No.2 BFM number...

• Electromagnetic compatibility or EMC must be considered before using the LX3V-4TC. • We recommend that the thermocouple sensors used, should be fitted with a form of seild or screening as protection against EMC noise. • If some form of cable protection is used, the "Shield" must be terminated at the terminals as shown in • Because of the delicate nature of all analog signals, failure to take good EMC precautions could lead to • EMC noise induced errors; up to ±10% of actual values. This is an absolute worst case figure, users who do take good precautions can expect operation within normal...