Wiki source code of LX3V-4PT

Last modified by Wecon on 2025/09/03 21:02

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Wecon 1.1 1 = **1 Introduction** =
2
3 The LX3V-4PT V2 analog block amplifies the input from four platinum temperature sensors (PT 100, 3 wires, and 100 Ω) and converts the data into 12 bit reading’s stored in the Main Processing Unit (MPU). Both Centigrade (°C) and Fahrenheit (°F) can be read. Reading resolution is 0.2°C to 0.3°C / 0.36°F to 0.54°F.
4
5 All data transfer and parameter settings can be controlled and adjusted by the software of the LX3V-4PT V2, which is done by the TO/FROM application instructions of the LX3V main unit.
6
7 LX3V-4PT V2 consumes 5V voltage from LX3V main unit or active extension unit, 90ma current of power supply.
8
9 = **2 Dimensions** =
10
11 (% style="text-align:center" %)
12 [[image:LX3V-4PTv2_html_a6a53d0d23851698.png||height="412" width="1000" class="img-thumbnail"]]
13
14 1. Extension cable and connector
15 1. Com LED & 24V LED: Light when communicating& light when connect to 24V
16 1. PT LED: Channels indicator
17 1. LINK: Indicator between PLC and module
18 1. Module name
19 1. Analog signal output terminal
20 1. Extension module interface
21 1. DIN rail mounting slot
22 1. DIN rail hook
23 1. Mounting holes (φ4.5)
24
25 (% class="table-bordered" style="width:1079.5px" %)
26 |=(% rowspan="2" style="width: 100px;" %)**Name**|=(% rowspan="2" style="width: 269px;" %)**Description**|=(% colspan="3" style="width: 737px;" %)**States**
27 |(% style="width:74px" %)**Blink**|(% style="width:316px" %)**OFF**|(% style="width:300px" %)**ON**
28 |(% style="width:100px" %)COM|(% style="width:269px" %)Indicator of communication board and acquisition board|(% style="width:243px" %)Communicating|(% style="width:253px" %)Communication failed or abnormal|(% style="width:209px" %)~-~-
29 |(% style="width:100px" %)ERR|(% style="width:269px" %)Factory calibration lamp|(% style="width:243px" %)~-~-|(% style="width:253px" %)Calibrated|(% style="width:209px" %)Not calibrated
30 |(% style="width:100px" %)24V|(% style="width:269px" %)Power lamp|(% style="width:243px" %)~-~-|(% style="width:253px" %)Abnormal|(% style="width:209px" %)Normal
31 |(% style="width:100px" %)LINK|(% style="width:269px" %)Communication indicator between PLC and module|(% style="width:243px" %)Communicating|(% style="width:253px" %)Communication failed or abnormal|(% style="width:209px" %)Software failure or hardware failure
32 |(% style="width:100px" %)PT 1|(% style="width:269px" %)Channel 1 lamp|(% rowspan="4" style="width:243px" %)Temperature exceeds range or the channel is not connected|(% rowspan="4" style="width:253px" %)Channel is closed|(% rowspan="4" style="width:209px" %)Temperature is in normal range
33 |(% style="width:100px" %)PT 2|(% style="width:269px" %)Channel 2 lamp
34 |(% style="width:100px" %)PT 3|(% style="width:269px" %)Channel 3 lamp
35 |(% style="width:100px" %)PT 4|(% style="width:269px" %)Channel 4 lamp
36
37 **Using crimp terminations**
38
39 (((
40 * Be sure to use the crimp-style terminals that satisfy the dimensional requirements shows in the left figure.
41 * Apply 0.5 to 0.8 N.m (5 to 8 kgf.cm) torque to tighten the terminals to prevent abnormal operation.
42
43 (% style="text-align:center" %)
44 [[image:LX3V-4PTv2_html_67891e8f02a25438.png||height="199" width="300" class="img-thumbnail"]]
45 )))
46
47 = **3 Terminal Layouts** =
48
49 (((
50 (% style="text-align:center" %)
51 [[image:LX3V-4PTv2_html_f2b39d82729377d1.png||height="379" width="400" class="img-thumbnail"]]
52
53 * The cable of the PT100 sensor or a twisted shielded cable should be used for the analog input cable. This analog input cable should be wired separately from power lines or any other lines which may induce noise.The three wire method improves the accuracy of the sensor by compensating voltage drops.
54 * If there is electrical noise, connect the frame ground terminal (FG) with the ground terminal.
55 )))
56
57 * Connect the ground terminal on the LX3V-4PTV2 unit with the grounded terminal on the base unit. Use class 3 grounding on the base unit, if grounding is possible.
58 * Either an external or the 24V built-in supply in the programmable controller may be used.
59
60 (((
61 For example: the same color wire (red) is connected to I+ and L+ terminals, and the white wire is connected to L-
62
63 (% style="text-align:center" %)
64 [[image:LX3V-4PTv2_html_9ba5e6ed20b1760.jpg||height="933" width="700" class="img-thumbnail"]]
65 )))
66
67 For additional data regarding EMC considerations please see section 7.0
68
69 = **4 Installation instruction** =
70
71 **Environmental specification**
72
73 (% class="table-bordered" %)
74 |=**Item**|=**Specification**
75 |Environmental specifications (excluding following)|Same as those for the LX3V base unit
76 |Dielectric withstand voltage|500V AC, 1min (between all terminals and ground)
77
78 **Power supply specification**
79
80 (% class="table-bordered" %)
81 |=(% scope="row" style="width: 246px;" %)**Item**|=(% style="width: 835px;" %)**Description**
82 |=(% style="width: 246px;" %)Analog circuits|(% style="width:835px" %)±24V DC±10%,55ma
83 |=(% style="width: 246px;" %)Digital circuits|(% style="width:835px" %)5V DC,90ma(internal power supply from base unit)
84
85 **Performance specification**
86
87 (% class="table-bordered" %)
88 |=(% rowspan="2" scope="row" %)**Item**|**Centigrade**|**Fahrenheit**
89 |=(% colspan="2" %)**Both °C and °F readings are available by reading the appropriate buffer memory area.**
90 |=**Analog input signal**|(% colspan="2" %)Platinum temperature PT 100 sensors (100 Ω), 3-wire, 4-channel (CH1, CH2,CH3, CH4), 3850 PPM/°C
91 |=**Current to sensor**|(% colspan="2" %)1 ma. Sensor : 100 Ω PT 100
92 |=**Compensated range**|100°C to 600°C|-148°F to +1112°F
93 |=(% rowspan="2" %)**Digital output**|-1000 to 6000|-1480 to 11120
94 |=(% colspan="2" %)12-bit conversion 11 data bits +1 sign bit
95 |=**Minimum resolvable temp.**|0.2°C to 0.3°C|0.36°F to 0.54°F
96 |=**Overall accuracy**|(% colspan="2" %)(((
97 ±1% full scale (compensated range)
98
99 -see section 7.0 for special EMC considerations
100 )))
101 |=**Conversion speed**|(% colspan="2" %)4 channels 15ms
102
103 **Analog input**
104
105 (% class="table-bordered" %)
106 |=(% scope="row" %)**Feature Conversion**|(((
107 (% style="text-align:center" %)
108 [[image:LX3V-4PTv2_html_893a440b9a122014.gif||height="197" width="600" class="img-thumbnail"]]
109 )))
110
111 **Other**
112
113 (% class="table-bordered" %)
114 |=(% scope="row" %)**Item**|=**Description**
115 |=Isolation|Photo-coupler isolation between analog and digital circuits. DC/DC converter isolation of power from LX3V MPU. No isolation between analog channels.
116 |=Total points|8 points taken from the LX3V expansion bus (can be either inputs or outputs)
117
118 **Buffer memory**
119
120 (% class="table-bordered" %)
121 |=(% scope="row" style="width: 182px;" %)**BFM**|=(% style="width: 893px;" %)**Description**
122 |=(% style="width: 182px;" %)*#1→ #4|(% style="width:893px" %)CH1 to CH4 Averaged temperature reading to be averaged (1 to 4,096) Default = 8
123 |=(% style="width: 182px;" %)*#5→ #8|(% style="width:893px" %)CH1 to CH4 Averaged temperature in 0.1°C units
124 |=(% style="width: 182px;" %)*#9→ #12|(% style="width:893px" %)CH1 to CH4 Present temperature in 0.1°C units
125 |=(% style="width: 182px;" %)*#13→ #16|(% style="width:893px" %)CH1 to CH4 Averaged temperature in 0.1°F units
126 |=(% style="width: 182px;" %)*#17→ #20|(% style="width:893px" %)CH1 to CH4 Present temperature in 0.1°F units
127 |=(% style="width: 182px;" %)*#21→ #27|(% style="width:893px" %)Reserved
128 |=(% style="width: 182px;" %)*#28|(% style="width:893px" %)Digital range error latch
129 |=(% style="width: 182px;" %)#29|(% style="width:893px" %)Error status
130 |=(% style="width: 182px;" %)#30|(% style="width:893px" %)Identification code K2040
131 |=(% style="width: 182px;" %)#31|(% style="width:893px" %)Software version
132
133 1. The numbers of samples to be averaged are assigned in BFMs #1 to #4. Only the range 1 to 4096 is valid. Values outside this range are ignored. The default value of 8 is used.
134 1. A number of recently converted readings are averaged to give a smoother read out. The averaged data is stored in BFMs #5 to #8 and #13 to #16.
135 1. BFMs #9 to #12 and #17 to #20 store the current value of the input data. This value is in units of 0.1°C or 0.1°F, but the resolution is only 0.2°C to 0.3°C or 0.36°F to 0.54°F.
136
137 **States information**
138
139 **Buffer memory BFM#28: Digital range error latch**
140
141 * BFM #29 b10 (digital range error) is used to judge whether the measured temperature is within the unit’s range or not.
142 * BFM #28 latches the error status of each channel and can be used to check for thermocouple disconnection.
143
144 (% class="table-bordered" %)
145 |=**B15 or b8**|=**B7**|=**B6**|=**B5**|=**B4**|=**B3**|=**B2**|=**B1**|=**B0**
146 |(% rowspan="2" %)Not used|High|Low|High|Low|High|Low|High|Low
147 |(% colspan="2" %)CH4|(% colspan="2" %)CH3|(% colspan="2" %)CH2|(% colspan="2" %)CH1
148
149 * **Low: **Latches ON when temperature measurement data goes below the lowest temperature measurement limit.
150 * **High:** Turns ON when temperature measurement data goes above the highest temperature measurement limit, or when a thermocouple is disconnected.
151
152 When an error occur the temperature data before the error is latched. If the measured value returns to within valid limits the temperature data returns to normal operation. (Note: The error remains latched in (BFM #28))
153
154 An error can be cleared by writing K0 to BFM #28 using the TO instruction or turning off the power.
155
156 **Buffer memory BFM#29: Error states**
157
158 (% class="table-bordered" %)
159 |=(% scope="row" %)**BFM#29 Bit device**|=**ON**|=**OFF**
160 |=B0: Error|When any of b1 to b3 is ON A/D conversation is stopped for the error channel|No error
161 |=B1: Reserved|Reserved|Reserved
162 |=B2: Power source|24V DC power supply failure|Power supply normal
163 |=B3: Hardware error|A/D converter or other hardware failure|Hardware normal
164 |=B4 to b9: Reserved|Reserved|Reserved
165 |=B10: Digital range error|Digital output/analog input value is outside the specified range.|Digital output value is normal
166 |=B11: Averaging error|Selected number of averaged results is outside the available range. See BFM#1 to #4|Averaging is normal (between 1 to 4096)
167 |=B12 to b15: Reserved|Reserved|Reserved
168
169 **Identification Code Buffer Memory BFM #30**
170
171 The identification code or ID number for module is read from buffer memory BFM #30 using the FROM command.
172
173 This number for the LX3V-4PT V2 unit is K2040.
174
175 The programmable controller can use this facility in its program to identify the special block before commencing data transfer from and to the special block
176
177 **System diagram**
178
179 (% style="text-align:center" %)
180 [[image:LX3V-4PTv2_html_2fc59ad0f23cead5.png||height="322" width="600" class="img-thumbnail"]]
181
182 = **5 Example** =
183
184 In the program shown below, the LX3V-4PT V2 expansion module occupies the position of special block number 2 (that is the third closest block to the programmable controller). The averaging amount is four. The averaged values in degrees C of input channels CH1 to CH4 are stored respectively in data registers D0 to D3.
185
186 **Example 1**
187
188 This initial step checks that the expansion module placed at position 2 is actually an LX3V-4PT V2, i.e. Its unit identification number is 2040 (BFM #30). This step is optional, but it provides a software check that the system has been configured correctly.
189
190 (((
191 Block No.2 BFM #30→(D10)
192
193 When (K2040)= (D10), M1=ON. i.e. when identification code is K2030, M1=ON.
194
195 (% style="text-align:center" %)
196 [[image:LX3V-4PTv2_html_6ee9c1fce665d3a.png||height="215" width="600" class="img-thumbnail"]]
197 )))
198
199 **Example 2**
200
201 (((
202 Transfer the error status to (M25 to M10), when error is found, M10=ON
203
204 (% style="text-align:center" %)
205 [[image:LX3V-4PTv2_html_b279e0b0c3c02c1b.png||height="236" width="600" class="img-thumbnail"]]
206 )))
207
208 This step provides optional monitoring of the LX3V-4PT V2 Error Buffer Memory (#29). If there is an Error on the LX3V-4PT V2, bit b0 of BFM #29 will be set on. This can be read by this program step, and output as a bit device in the PLC (Y010 in this example). Additional Error devices can be output in a similar manner, e.g. B10 BFM #29 Digital range error. (See example 3)
209
210 **Example 3**
211
212 M10 represents b0 of BFM#29
213
214 M20 represents b10 of BFM#29
215
216 (% style="text-align:center" %)
217 [[image:LX3V-4PTv2_html_15bac225fffa5e5.png||height="129" width="500" class="img-thumbnail"]]
218
219 (% style="text-align:center" %)
220 [[image:LX3V-4PTv2_html_d59884b711c0f883.png||height="149" width="500" class="img-thumbnail"]]
221
222 * (K4)-> (BFM#1), (K4)-> (BFM#2). Number of samples is changed to 4 on both CH1 and CH2.
223 * (BFM#5)-> (D0), (BFM#6)-> (D1). Transfer the average temperature value in °C to the data registers.
224
225 This step is the actual reading of the LX3V-4PT V2 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.
226
227 The "FROM" instruction reads the average temperatures (BFM #5 to #8) for input channels CH1 and CH2 of the LX3V-4PT V2. If direct temperature readings are required BFM #9 and #10 should be read instead, e.g.
228
229 (% style="text-align:center" %)
230 [[image:LX3V-4PTv2_html_24b3ab2479ed3b38.png||height="126" width="500" class="img-thumbnail"]]
231
232 = **6 Diagnostics** =
233
234 **Preliminary checks**
235
236 1. Check whether the input wiring and/or extension cables are properly connected on LX3V-4PT V2 analog special function block.
237 1. Check that the LX3V system configuration rules have not been broken, i.e. The number of special function blocks does not exceed 16 and the total system I/O is equal or less than 256 I/O.
238 1. Ensure that the correct operating range has been selected for the application.
239 1. Check that there is no power overload on either the 5V or 24V power sources, remember the loading on a LX3V main unit or a powered extension unit varies according to the number of extension blocks or special function blocks connected.
240 1. Put the LX3V main unit into RUN.
241
242 **Error checking**
243
244 * If the LX3V-4PT V2 special function block does not seem to operate normally, check the following items.
245
246 Check the status of the POWER LED.
247
248 Lit: The extension cable is properly connected.
249
250 Otherwise: Check the connection of the extension cable.
251
252 * Check the external wiring.
253 * Check the status of the “24V” LED (top right corner of the LX3V-4PT V2 ).
254
255 Lit: LX3V-4PT V2 is OK; 24V DC power source is OK.
256
257 Otherwise: Possible 24VDC power failure, if OK possible LX3V-4PT V2 failure.
258
259 * Check the status of the “A/D” LED (top right corner of the LX3V-4PT V2).
260
261 Lit: A/D conversion is proceeding normally.
262
263 Otherwise: Check buffer memory #29 (error status). If any bits (b2 and b3) are ON, then this is why the A/D LED is OFF.
264
265 **Checking special function block numbers**
266
267 Other special units of blocks that use FROM/TO commands, such as analog input blocks, analog output blocks and high-speed counter blocks, can be directly connected to the base unit of the LX3V programmable controller or to the right side of other extension blocks or units. Each special block is consecutively numbered from 0 to 15 beginning from the one closest to the base unit. A maximum of 16 special blocks can be connected.
268
269 (% style="text-align:center" %)
270 [[image:LX3V-4PTv2_html_82dc23faccc052c2.png||height="349" width="1000" class="img-thumbnail"]]
271
272 = **7 EMC considerations** =
273
274 * Electromagnetic compatibility or EMC must be considered before using the LX3V-4PT V2.
275 * WECON recommends that the thermocouple sensors used, should be fitted with a form of seild or screening as protection against EMC noise.
276 * If some form of cable protection is used, the “Shield” must be terminated at the terminals as shown in chapter 3.
277 * 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 tolerances. EMC considerations should include selection of good quality cables, good routing of those cables away from potential noise sources.
278 * Additionally it is recommended that signal averaging is used as this will reduce the effects of random noise “spikes”