CM3 RTD Module Buffer Memory

To write to buffer memory, use the TO instruction.

To read from buffer memory, use the FROM instruction.

Please refer to the table below for writing to and reading from buffer memory.

CM3-SP04ERO Buffer Memory
Memory Address		Details	Read	Write	Link
Hexadecimal	Decimal
00H	0	RTD conversion Enable/Disable	✓	✓	RTD conversion Enable/Disable
01H	1	Channel 1 Temperature detection value (°C)	✓	-	Temperature detection value (°C)
02H	2	Channel 2 Temperature detection value (°C)	✓	-
03H	3	Channel 3 Temperature detection value (°C)	✓	-
04H	4	Channel 4 Temperature detection value (°C)	✓	-
05H	5	Reserved	-	-
06H	6	Reserved	-	-
07H	7	Reserved	-	-
08H	8	Reserved	-	-
09H	9	Designate RTD type	✓	✓	Designate RTD type
0AH	10	Digital output setting 1	✓	✓	Digital output setting
0CH	12	Channel 1 Temperature detection value (°F)	✓	-	Temperature detection value (°F)
0DH	13	Channel 2 Temperature detection value (°F)	✓	-
0EH	14	Channel 3 Temperature detection value (°F)	✓	-
0FH	15	Channel 4 Temperature detection value (°F)	✓	-
10H	16	Reserved	-	-
11H	17	Reserved	-	-
12H	18	Reserved	-	-
13H	19	Reserved	-	-
13H	19	Information for operation channel	✓	-	Information for operation channel
14H	20	Designate RTD type	✓	✓	Designate RTD type
15H	21	Channel 1 Digital conversion value	✓	-	Digital conversion value
16H	22	Channel 2 Digital conversion value	✓	-
17H	23	Channel 3 Digital conversion value	✓	-
18H	24	Channel 4 Digital conversion value	✓	-
19H	25	Reserved	-	-
1AH	26	Reserved	-	-
1BH	27	Reserved	-	-
1CH	28	Reserved	-	-
1DH	29	Digital output setting 2	✓	✓	Digital output setting
1EH	30	Designate Average Process	✓	✓	Designate Average Process
1FH	31	Channel 1 Error code	✓	-	Error code
20H	32	Channel 2 Error code	✓	-
21H	33	Channel 3 Error code	✓	-
22H	34	Channel 4 Error code	✓	-
23H	35	Reserved	-	-
24H	36	Reserved	-	-
25H	37	Reserved	-	-
26H	38	Reserved	-	-
27H	39	Reserved	-	-
28H	40	Requesting data for calibration	✓	✓
29H	41	Channel 1 Maximum temperature input value	✓	✓	Maximum temperature input value
2AH	42	Channel 2 Maximum temperature input value	✓	✓
2BH	43	Channel 3 Maximum temperature input value	✓	✓
2CH	44	Channel 4 Maximum temperature input value	✓	✓
2DH	45	Reserved	-	-
2EH	46	Reserved	-	-
2FH	47	Reserved	-	-
30H	48	Reserved	-	-
31H	49	Minimum and Maximum Scale setting data	✓	✓	Minimum and Maximum Scale setting data
32H	50	Minimum and Maximum set error	✓	-	Minimum and Maximum set error
33H	51	Channel 1 Minimum temperature input value	✓	✓	Minimum temperature input value
34H	52	Channel 2 Minimum temperature input value	✓	✓
35H	53	Channel 3 Minimum temperature input value	✓	✓
36H	54	Channel 4 Minimum temperature input value	✓	✓
37H	55	Reserved	-	-
38H	56	Reserved	-	-
39H	57	Reserved	-	-
3AH	58	Reserved	-	-
3BH	59	Channel 1 Average time/filter coefficient setting	✓	✓	Average time/filter coefficient setting
3CH	60	Channel 2 Average time/filter coefficient setting	✓	✓
3DH	61	Channel 3 Average time/filter coefficient setting	✓	✓
3EH	62	Channel 4 Average time/filter coefficient setting	✓	✓

RTD Conversion Enable/Disable

• Setup RTD conversion enable or disable for each channel.
• The initial value is thermocouple conversion disable.
• In order to save the set value to the RTD module, Requesting to save set value (Yn.2) must be ON/OFF.
• The set value is stored in EEPROM and is operated by the previous set value when the power is turned ON/OFF.

Channel Enable/Disable Mapping
Bit 15	Bit 14	Bit 13	Bit 12	Bit 11	Bit 10	Bit 9	Bit 8	Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
0	0	0	0	0	0	0	0	0	0	0	0	Channel 4	Channel 3	Channel 2	Channel 1

• Bit 4 ~ Bit 15 are fixed to 0 by default.

• Channel 1 ~ 4 (bits 0 ~ 3) have RTD conversion disabled if the bit is 0.

• Channel 1 ~ 4 (bits 0 ~ 3) have RTD conversion enabled if the bit is 1.

Temperature Detection Value (°C)

• The temperature detection value stores the temperature value detected by RTD conversion.
• The temperature conversion value range is -200°C ~ 600°C.
  • If the value is out of the range, -250°C ~ 650°C is measured.
    • If the value is out of this range, -250°C ~ 650°C is fixed.

Designate RTD Type

• The initial value is PT100.
• In order to save the set value to the RTD module, Requesting to save set value (Yn.2) must be ON/OFF.
• The set value is stored in EEPROM and is operated by the previous set value when the power is turned ON/OFF.

Bit Mapping
Most Significant Bit								Least Significant Bit
Channel 4				Channel 3				Channel 2				Channel 1
0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

The PLC-S only uses buffer memory address 9 (09H). RTD will be used as below:

RTD Type Setup
Memory Address 9 (09H)	RTD Type
0 (0000)	PT100
1 (0001)	JPT100
2 (0010)	PT1000
3 (0011)	Ni1000 (DIN43760)
4 (0100)	Ni1000 (TCR5000)

Temperature Detection Value (°F)

• The temperature detection value stores the temperature value detected by RTD conversion.
  • The temperature, in Fahrenheit, converted by the RTD module is stored.
  • The actual temperature (the first decimal digit × 10) is stored into memory.
• The temperature conversion value range is -392°F ~ 1,112°F.
  • If the value is out of the range, -482°F ~ 1,202°F is measured.
    • If the value is out of this range, -482°F ~ 1,202°F is fixed.

Information for Operation Channel

• The information for a channel under normal conversion among conversion-enabled channels is displayed.
• The bit for disconnected channel among conversion-enabled channels is 0 while the bit for channels under normal conversion is 1.
• The bit for conversion-disabled channels store 0.

Digital Conversion Value

• If the temperature measured by the RTD module is -200°C (-328°F), it is stored as the digital value 0 (-8,000).
• If the temperature measured by the RTD module is 600°C* (1,112°F), it is stored as the digital value 16,000 (8,000).
• If the user input minimum and maximum values:
  • If the minimum temperature is measured, 0 (-8,000) is stored.
  • If the maximum temperature is measured, 16,000 (8,000) is stored.

Digital Output Setting

• Select the following ranges as a digital output value:
  • 0 ~ 16,000
  • -8,000 ~ 8,000
  • -192 ~ 16,191
  • -8,192 ~ 8,191
• If the range -192 ~ 16,191 or -8,192 ~ 8,191 is selected, the RTD module displays the minimum and maximum measured temperature for each thermocouple by 0 ~ 16,000 or -8,000 ~ 8,000.
  • If the input value exceeds either range, the RTD module displays -192 ~ 16,191 or -8,192 ~ 8,191.
• The initial value is set to -192 ~ 16,191.
• In order to save the set value to the RTD module, Requesting to save set value (Yn.2) must be ON/OFF.
• The set value is stored in EEPROM and is operated by the previous set value when the power is turned ON/OFF.

Bit Mapping
Bit 15	Bit 14	Bit 13	Bit 12	Bit 11	Bit 10	Bit 9	Bit 8	Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 9	Bit 0
0	0	0	0	0	0	0	0	0	0	0	0	Channel 4	Channel 3	Channel 2	Channel 1

Digital Output Value
Buffer Memory 10 (0AH)	Buffer Memory 29 (1DH)	Digital Output Type
0	0	-192 ~ 16,191
0	1	-8,192 ~ 8,191
1	0	0 ~ 16,000
1	1	-8,000 ~ 8,000

Designate Average Process

• Set the average process of the RTD module to enable/disable.
• The initial value for the average process of all channels is disabled.
• In order to save the set value to the RTD module, Requesting to save set value (Yn.2) must be ON/OFF.
• The set value is stored in EEPROM and is operated by the previous set value when the power is turned ON/OFF.

Average Process Enable/Disable Mapping
Bit 15	Bit 14	Bit 13	Bit 12	Bit 11	Bit 10	Bit 9	Bit 8	Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
0	0	0	0	0	0	0	0	0	0	0	0	Channel 4	Channel 3	Channel 2	Channel 1

• Channel 1 ~ 4 (bits 0 ~ 3) have average process disabled if the bit is 0.
• Channel 1 ~ 4 (bits 0 ~ 3) have average process enabled if the bit is 1.

Error Code

• The error code detected by the RTD module is stored.
• The error is maintained before it is cleared or the power is turned OFF.
  • If another error occurs before the previous error is not cleared, the newly generated error is ignored.
• The error code is a decimal number.

Error Code
Value	Description
01	Disconnection (A or B)
02	Disconnection (b or both A and B)
04	If the measured value exceeds the minimum or maximum range
100	System error Contact the CIMON warranty team

Minimum and Maximum Temperature Input Value

• In order for the minimum or maximum set value to be effective, make sure the corresponding bit for temperature set data (Buffer Memory Address 49 (31H)) is set to 1 and the Requesting to save set value (Yn.2) is ON/OFF.
• For the minimum and maximum setting, if the minimum value input by the user is larger than the maximum value, the bit for the corresponding channel becomes 1.
• The set value stored in EEPROM and is operated by the previous set value when the power is turned ON/OFF.
• If the maximum value is smaller than the minimum value, an error occurs.

Minimum and Maximum Scale Setting Data

Minimum and Maximum Scale Setting Data Enable/Disable Mapping
Bit 15	Bit 14	Bit 13	Bit 12	Bit 11	Bit 10	Bit 9	Bit 8	Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
0	0	0	0	0	0	0	0	0	0	0	0	Channel 4	Channel 3	Channel 2	Channel 1

• Channel 1 ~ 4 (bits 0 ~ 3) have the setting disabled if the bit is 0.
  • The scale values of PT100, JPT100, and PT1000 are -200°C ~ 600°C (-328°F ~ 1,112°F).
  • The scale values of Ni1000_DIN and Ni1000_TCR are -50°C ~ 160°C (-58°F ~ 320°F)
• Channel 1 ~ 4 (bits 0 ~ 3) have the setting enabled if the bit is 1.

Minimum and Maximum Set Error

Minimum and Maximum Set Error Mapping
Bit 15	Bit 14	Bit 13	Bit 12	Bit 11	Bit 10	Bit 9	Bit 8	Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
0	0	0	0	0	0	0	0	0	0	0	0	Channel 4	Channel 3	Channel 2	Channel 1

• Channel 1 ~ 4 (bits 0 ~ 3) have no errors if the bit is 0.
• Channel 1 ~ 4 (bits 0 ~ 3) have errors enabled if the bit is 1.
  • If the maximum value is smaller than the minimum value, an error occurs.
  • If PT100, JPT100, or PT1000:
    • Errors occur if the minimum value is less than -200 or the maximum value is greater than 600.
  • If Ni1000_DIN or Ni1000_TCR:
    • Errors occur if the minimum value is less than -50 or the maximum value is greater than 160.

Average Time/Filter Coefficient Setting

• The average time/filter coefficient setting stores the set filter coefficient value and the average time set value.
• The average time set value for 1 BYTE (lower WORD) is 1 ~ 255 seconds.
• The filter coefficient set value for 1 BYTE (upper WORD) is 0% ~ 70%.
• When the filter function is not used, the value is 0.

Average Time/Filter Coefficient Setting Example

• Example: if the average time for channel 1 is 2 seconds amd the filter coefficient is 50:
  • H3202 (12,802) is stored into the buffer memory address 59 (3BH).

Average Time/Filter Coefficient Example
Filter Coefficient								Average Time
Bit 15	Bit 14	Bit 13	Bit 12	Bit 11	Bit 10	Bit 9	Bit 8	Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0	Value
0	0	1	1	0	0	1	0	0	0	0	0	0	0	1	0	H3202 12,802

• If the converted temperature has severe variations due to external noise, follow below:
  • The width for variations for the converted temperature is limited before it is stored in buffer memory.
  • The range of the setting value is 0% ~ 70%.

Example: If the temperature changes as shown in the table below: it is a value that is stored in buffer memory.

Example
Conversion temperature value Digital filter value	10	15	13	9	14	12	9	5	15
10%	-	14.5	13.2	9.4	13.5	12.2	9.3	5.4	14.0
70%	-	11.5	12.0	11.1	12.0	12.0	11.1	9.3	11.0

Current value = current value + (previous value - current value) × filter coefficient (%) ÷ 100