Page top

# Temperature Controllers

These Controllers receive sensor signals and control heaters or other devices to maintain a preset temperature. They can also be used for humidity, pressure, and flowrate control. OMRON also provides temperature and humidity sensors.

 Introduction Features Principles Classifications Engineering Data Further Information Explanation of Terms Troubleshooting
﻿

[[Connection Examples between Temperature Controllers and SSRs]]

Calculating the Number of Connectable SSRs in Parallel
(A): The maximum load current for the voltage output (for driving SSR) of each Temperature Controller.
(B): SSR input current
(A) ÷ (B) = Number of connectable SSRs

*1. Two G3PE-BL SSRs can be connected.
*2. One G3PE-BL SSR can be connected.
*3. Two G3PA-BL SSRs can be connected.
*4. One G3PA-BL SSR can be connected.
*5. Two of the -UTU models of the G3NA SSRs can be connected.
*6. One of the -UTU model of the G3NA SSRs can be connected.
Four of the 480-VAC models of the G3NA SSRs can be connected.

Thermocouple Standard Potential Difference

Thermocouples generate voltage according to the temperature difference. The potential difference is prescribed by Japanese Industrial Standards (JIS).
The following chart gives the potential difference for R, S, K, and J thermocouples when the temperature of the reference junction is 0°C.

(Standards Published in 2015)

JIS C 1602-2015 (Unit: μV)

 Category Temperature(°C) 0 10 20 30 40 50 60 70 80 90 R standardpotentialdifference 0 0 54 111 171 232 296 363 431 501 573 100 647 723 800 879 959 1,041 1,124 1,208 1,294 1,381 200 1,469 1,558 1,648 1,739 1,831 1,923 2,017 2,112 2,207 2,304 300 2,401 2,498 2,597 2,696 2,796 2,896 2,997 3,099 3,201 3,304 400 3,408 3,512 3,616 3,721 3,827 3,933 4,040 4,147 4,255 4,363 500 4,471 4,580 4,690 4,800 4,910 5,021 5,133 5,245 5,357 5,470 600 5,583 5,697 5,812 5,926 6,041 6,157 6,273 6,390 6,507 6,625 700 6,743 6,861 6,980 7,100 7,220 7,340 7,461 7,583 7,705 7,827 800 7,950 8,073 8,197 8,321 8,446 8,571 8,697 8,823 8,950 9,077 900 9,205 9,333 9,461 9,590 9,720 9,850 9,980 10,111 10,242 10,374 1,000 10,506 10,638 10,771 10,905 11,039 11,173 11,307 11,442 11,578 11,714 1,100 11,850 11,986 12,123 12,260 12,397 12,535 12,673 12,812 12,950 13,089 1,200 13,228 13,367 13,507 13,646 13,786 13,926 14,066 14,207 14,347 14,488 1,300 14,629 14,770 14,911 15,052 15,193 15,334 15,475 15,616 15,758 15,899 1,400 16,040 16,181 16,323 16,464 16,605 16,746 16,887 17,028 17,169 17,310 1,500 17,451 17,591 17,732 17,872 18,012 18,152 18,292 18,431 18,571 18,710 1,600 18,849 18,988 19,126 19,264 19,402 19,540 19,677 19,814 19,951 20,087 1,700 20,222 20,356 20,488 20,620 20,749 20,877 21,003 --- --- --- S standardpotentialdifference 0 0 55 113 173 235 299 365 433 502 573 100 646 720 795 872 950 1,029 1,110 1,191 1,273 1,357 200 1,441 1,526 1,612 1,698 1,786 1,874 1,962 2,052 2,141 2,232 300 2,323 2,415 2,507 2,599 2,692 2,786 2,880 2,974 3,069 3,164 400 3,259 3,355 3,451 3,548 3,645 3,742 3,840 3,938 4,036 4,134 500 4,233 4,332 4,432 4,532 4,632 4,732 4,833 4,934 5,035 5,137 600 5,239 5,341 5,443 5,546 5,649 5,753 5,857 5,961 6,065 6,170 700 6,275 6,381 6,486 6,593 6,699 6,806 6,913 7,020 7,128 7,236 800 7,345 7,454 7,563 7,673 7,783 7,893 8,003 8,114 8,226 8,337 900 8,449 8,562 8,674 8,787 8,900 9,014 9,128 9,242 9,357 9,472 1,000 9,587 9,703 9,819 9,935 10,051 10,168 10,285 10,403 10,520 10,638 1,100 10,757 10,875 10,994 11,113 11,232 11,351 11,471 11,590 11,710 11,830 1,200 11,951 12,071 12,191 12,312 12,433 12,554 12,675 12,796 12,917 13,038 1,300 13,159 13,280 13,402 13,523 13,644 13,766 13,887 14,009 14,130 14,251 1,400 14,373 14,494 14,615 14,736 14,857 14,978 15,099 15,220 15,341 15,461 1,500 15,582 15,702 15,822 15,942 16,062 16,182 16,301 16,420 16,539 16,658 1,600 16,777 16,895 17,013 17,131 17,249 17,366 17,483 17,600 17,717 17,832 1,700 17,947 18,061 18,174 18,285 18,395 18,503 18,609 --- --- --- K standardpotentialdifference 0 0 397 798 1,203 1,612 2,023 2,436 2,851 3,267 3,682 100 4,096 4,509 4,920 5,328 5,735 6,138 6,540 6,941 7,340 7,739 200 8,138 8,539 8,940 9,343 9,747 10,153 10,561 10,971 11,382 11,795 300 12,209 12,624 13,040 13,457 13,874 14,293 14,713 15,133 15,554 15,975 400 16,397 16,820 17,243 17,667 18,091 18,516 18,941 19,366 19,792 20,218 500 20,644 21,071 21,497 21,924 22,350 22,776 23,203 23,629 24,055 24,480 600 24,905 25,330 25,755 26,179 26,602 27,025 27,447 27,869 28,289 28,710 700 29,129 29,548 29,965 30,382 30,798 31,213 31,628 32,041 32,453 32,865 800 33,275 33,685 34,093 34,501 34,908 35,313 35,718 36,121 36,524 36,925 900 37,326 37,725 38,124 38,522 38,918 39,314 39,708 40,101 40,494 40,885 1,000 41,276 41,665 42,053 42,440 42,826 43,211 43,595 43,978 44,359 44,740 1,100 45,119 45,497 45,873 46,249 46,623 46,995 47,367 47,737 48,105 48,473 1,200 48,838 49,202 49,565 49,926 50,286 50,644 51,000 51,355 51,708 52,060 1,300 52,410 52,759 53,106 53,451 53,795 54,138 54,479 54,819 --- --- J standardpotentialdifference 0 0 507 1,019 1,537 2,059 2,585 3,116 3,650 4,187 4,726 100 5,269 5,814 6,360 6,909 7,459 8,010 8,562 9,115 9,669 10,224 200 10,779 11,334 11,889 12,445 13,000 13,555 14,110 14,665 15,219 15,773 300 16,327 16,881 17,434 17,986 18,538 19,090 19,642 20,194 20,745 21,297 400 21,848 22,400 22,952 23,504 24,057 24,610 25,164 25,720 26,276 26,834 500 27,393 27,953 28,516 29,080 29,647 30,216 30,788 31,362 31,939 32,519 600 33,102 33,689 34,279 34,873 35,470 36,071 36,675 37,284 37,896 38,512 700 39,132 39,755 40,382 41,012 41,645 42,281 42,919 43,559 44,203 44,848 800 45,494 46,141 46,786 47,431 48,074 48,715 49,353 49,989 50,622 51,251 900 51,877 52,500 53,119 53,735 54,347 54,956 55,561 56,164 56,763 57,360 1,000 57,953 58,545 59,134 59,721 60,307 60,890 61,473 62,054 62,634 63,214 1,100 63,792 64,370 64,948 65,525 66,102 66,679 67,255 67,831 68,406 68,980 1,200 69,553 --- --- --- --- --- --- --- --- ---

Reference Temperature Characteristics for Platinum Resistance Thermometers (Ω)

JIS C 1604-2013

 Temperature(°C) -100 -0 Temperature(°C) 0 100 200 300 400 500 600 700 800 0 60.26 100 0 100 138.51 175.86 212.05 247.09 280.98 313.71 345.28 375.70 -10 56.19 96.09 10 103.9 142.29 179.53 215.61 250.53 284.3 316.92 348.38 378.68 -20 52.11 92.16 20 107.79 146.07 183.19 219.15 253.96 287.62 320.12 351.46 381.65 -30 48 88.22 30 111.67 149.83 186.84 222.68 257.38 290.92 323.3 354.53 384.60 -40 43.88 84.27 40 115.54 153.58 190.47 226.21 260.78 294.21 326.48 357.59 387.55 -50 39.72 80.31 50 119.4 157.33 194.1 229.72 264.18 297.49 329.64 360.64 390.48 -60 35.54 76.33 60 123.24 161.05 197.71 233.21 267.56 300.75 332.79 363.67 --- -70 31.34 72.33 70 127.08 164.77 201.31 236.7 270.93 304.01 335.93 366.7 --- -80 27.1 68.33 80 130.9 168.48 204.9 240.18 274.29 307.25 339.06 369.71 --- -90 22.83 64.3 90 134.71 172.17 208.48 243.64 277.64 310.49 342.18 372.71 --- -100 18.52 60.26 100 138.51 175.86 212.05 247.09 280.98 313.71 345.28 375.7 ---

JIS C 1604-1997

 Temperature(°C) -100 -0 Temperature(°C) 0 100 200 300 400 500 0 59.57 100 0 100 139.16 177.13 213.93 249.56 284.02 -10 55.44 96.02 10 103.97 143.01 180.86 217.54 253.06 --- -20 51.29 92.02 20 107.93 146.85 184.58 221.15 256.55 --- -30 47.11 88.01 30 111.88 150.67 188.29 224.74 260.02 --- -40 42.91 83.99 40 115.81 154.49 191.99 228.32 263.49 --- -50 38.68 79.96 50 119.73 158.29 195.67 231.89 266.94 --- -60 34.42 75.91 60 123.64 162.08 199.35 235.45 270.38 --- -70 30.12 71.85 70 127.54 165.86 203.01 238.99 273.8 --- -80 25.8 67.77 80 131.42 169.63 206.66 242.53 277.22 --- -90 21.46 63.68 90 135.3 173.38 210.3 246.05 280.63 --- -100 17.14 59.57 100 139.16 177.13 213.93 249.56 284.02 ---

Standard Temperature Characteristics for Element-interchangeable Thermistors

The thermistor can be used with E5C2, E5L and E5CS. Refer to the applicable thermistor in each datasheet.

JIS C 1611-1995

Note: Amount of change in resistance per degree C in the resistance deviation and specified temperature.

FAQs

The temperature error of the Temperature Controller seems large. What is the cause of this?

The following are possible causes.

The input type of the temperature sensor is incorrect (temperature sensor type setting).

Temperature sensor lead wires and power lines are in the same conduit, causing noise from the power lines (generally, display values will be unstable).
Countermeasures
Wire the lead wires and power lines in separate conduits, or wire them using a more direct path.

Connection between the Temperature Controller and thermocouple is using copper wires.
Countermeasures
Connect the thermocouple’s lead wires directly, or connect a compensating conductor that is suitable for the thermocouple.

The measurement location of the temperature sensor is not suitable.

The incorrect input shift value has been set.

Why does overshooting or undershooting occur?

The following are possible causes.

Narrow proportional band or small P constant

Short integral time or small I constant

Long derivative time or large D constant

ON/OFF control is enabled.

Control period is long for a control system with a fast thermal response.

Setting the overlap band in the heating and cooling control to a dead band by mistake.

Why are process values not being displayed correctly? And why is S.Err displayed?

The following are possible causes.

The input type in the Initial Setting Level is set incorrectly.

The temperature unit in the Initial Setting Level is set incorrectly.

The input shift value in the Adjustment Level is set incorrectly.

The data setting unit is incorrect.

The temperature sensor polarity or connected terminals are incorrect.

A temperature sensor has been connected that cannot be used with the installed Temperature Controller.

The temperature sensor has burnt out, shortcircuited, or deteriorated.

The temperature sensor has not been connected.

The thermocouple and compensating conductor types are incorrect.

A device using metal other than a thermocouple or compensating conductor has been connected between the thermocouple and Temperature Controller.

The connection terminal screws are loose and a contact failure occurs.

The thermocouple lead wires or compensating conductors are too long and the conductor resistance is affecting the Temperature Controller.

The resistance of the three conductors connected between the platinum resistance thermometer and the Temperature Controller terminals is different.

Noise emitted by devices around the Temperature Controller is affecting the Temperature Controller.

The temperature sensor lead wires and power lines are close, causing inductive noise from the power lines.

The thermal response is slow because the installation location of the temperature sensor is far from the control point.

The ambient operating temperature of the Temperature Controller exceeds the rating.

A wireless device is used around the Temperature Controller.

The temperature of the thermocouple-input-type terminal block varies due to heat radiated from peripheral devices.

Wind is blowing on the thermocouple-input-type terminal block.

Why does the process value exceeds the set point?

The following are possible causes.

The contacts for the relay driven by control outputs are welded.

The SSR has a short-circuit fault.

The PID constants are not suitable.

Restricted MV limit values are set.

The controlled object is heating by itself.

Why does the process value oscillate around the set point and not stabilize at the set point?

The following are possible causes.

Narrow proportional band or small P constant

Short integral time or small I constant

Long derivative time or large D constant

ON/OFF control is enabled.

Control period is long for a control system with a fast thermal response.

Setting the overlap band in the heating and cooling control to a dead band by mistake.

The heating capacity of the heater is too large for the heating capacity of the controlled object.

There is periodic external disturbance, which changes the heating capacity of the controlled object.

AT execution is in progress.

Why are communications not possible or why are there communications errors?

The following are possible causes.

The communications wiring is not correct.

The communications line has become disconnected.

The communications cable is broken.

The communications cable is too long.

The wrong communications cable has been used.

More than the specified number of communications devices are connected to the same communications path. (RS-422/RS-485 only)

Terminating resistance has not been connected at each end of the communications line. (RS-422/RS-485 only)

The specified power supply voltage is not being supplied to the Temperature Controller.

The specified power supply voltage is not being supplied to an Interface Converter.

The same baud rate and communications method are not being used by all of the Temperature Controllers, host devices, and other devices on the same communications line.

The unit number specified in the command frame is different from the unit number set by the Temperature Controller.

The same unit number as the Temperature Controller is being used for another node on the same communications line. (RS-422/RS-485 only)

There is a mistake in programming the host device.

The host device detects an error before it receives a response from the Temperature Controller.

The host device detects the absence of a response as an error after a broadcast command or a software reset command (except for SYSWAY).

The host device sent another command before receiving a response from the Temperature Controller.

The host device sent the next command too soon after receiving a response from the Temperature Controller.

The communications line became unstable when the Temperature Controller power was turned ON or interrupted, and the host device read the unstable status as data.

The communications data was corrupted by noise from the environment.

What precautions should be taken when extending the temperature sensor lead wires?

Platinum Resistance Thermometer: Pt and JPt
Make sure the three lead wires to be used for extension have the same resistance and are the same length.
Extending the lead wires will cause their resistance to influence the displayed temperature. Therefore, use wire with a thick conductor. (Extension lead wires are not available from OMRON. Use commercially available lead wires.)

Thermocouple: K, J, and R
Always use compensating lead wires for extension.
Use a compensating conductor designed for the connected thermocouple.
If you use a different type of compensating conductor from the thermocouple or if you use normal copper wires to extend, correct temperature measurement will not be possible.
Also, do not connect positive and negative incorrectly.

Thermistor
Use wire with a thick conductor for the lead-wire extensions. There is no polarity.

Common Precautions
The lead wires will be easily influenced by noise when they are extended. Be careful when performing wiring.

How much of an insertion length does the temperature sensor require?

Make sure the protective tube has sufficient length to touch the object to be measured, or to insert it into the object.
A length of at least 20 times the diameter of the protective tube is required for metal protective tubes. A length of at least 15 times the diameter of the protective tube is required for non-metal protective tubes.

Can the temperature sensor be used when it is bent?

Sheathed temperature sensors can be bent. The following precautions, however, should be taken.

The minimum permissible bend radius of a sheathed temperature sensor is five times the diameter of the protective tube. Do not bend the temperature sensor repeatedly in the same place.

Internal wiring may become disconnected or warped if the temperature sensor is bent to an acute angle and then stretched out again. Also, do not bend the welded section.

The protective tube is brittle when low temperatures are being measured. Do not bend the tube when it is cold.

To protect the measuring part of the sheathed temperature sensor, do not bend the sensor within 100 mm of the tip.