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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

Related Contents

Primary Contents



[[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)

CategoryTemperature(°C)0102030405060708090
R standard
potential
difference
0054111171232296363431501573
1006477238008799591,0411,1241,2081,2941,381
2001,4691,5581,6481,7391,8311,9232,0172,1122,2072,304
3002,4012,4982,5972,6962,7962,8962,9973,0993,2013,304
4003,4083,5123,6163,7213,8273,9334,0404,1474,2554,363
5004,4714,5804,6904,8004,9105,0215,1335,2455,3575,470
6005,5835,6975,8125,9266,0416,1576,2736,3906,5076,625
7006,7436,8616,9807,1007,2207,3407,4617,5837,7057,827
8007,9508,0738,1978,3218,4468,5718,6978,8238,9509,077
9009,2059,3339,4619,5909,7209,8509,98010,11110,24210,374
1,00010,50610,63810,77110,90511,03911,17311,30711,44211,57811,714
1,10011,85011,98612,12312,26012,39712,53512,67312,81212,95013,089
1,20013,22813,36713,50713,64613,78613,92614,06614,20714,34714,488
1,30014,62914,77014,91115,05215,19315,33415,47515,61615,75815,899
1,40016,04016,18116,32316,46416,60516,74616,88717,02817,16917,310
1,50017,45117,59117,73217,87218,01218,15218,29218,43118,57118,710
1,60018,84918,98819,12619,26419,40219,54019,67719,81419,95120,087
1,70020,22220,35620,48820,62020,74920,87721,003---------
S standard
potential
difference
0055113173235299365433502573
1006467207958729501,0291,1101,1911,2731,357
2001,4411,5261,6121,6981,7861,8741,9622,0522,1412,232
3002,3232,4152,5072,5992,6922,7862,8802,9743,0693,164
4003,2593,3553,4513,5483,6453,7423,8403,9384,0364,134
5004,2334,3324,4324,5324,6324,7324,8334,9345,0355,137
6005,2395,3415,4435,5465,6495,7535,8575,9616,0656,170
7006,2756,3816,4866,5936,6996,8066,9137,0207,1287,236
8007,3457,4547,5637,6737,7837,8938,0038,1148,2268,337
9008,4498,5628,6748,7878,9009,0149,1289,2429,3579,472
1,0009,5879,7039,8199,93510,05110,16810,28510,40310,52010,638
1,10010,75710,87510,99411,11311,23211,35111,47111,59011,71011,830
1,20011,95112,07112,19112,31212,43312,55412,67512,79612,91713,038
1,30013,15913,28013,40213,52313,64413,76613,88714,00914,13014,251
1,40014,37314,49414,61514,73614,85714,97815,09915,22015,34115,461
1,50015,58215,70215,82215,94216,06216,18216,30116,42016,53916,658
1,60016,77716,89517,01317,13117,24917,36617,48317,60017,71717,832
1,70017,94718,06118,17418,28518,39518,50318,609---------
K standard
potential
difference
003977981,2031,6122,0232,4362,8513,2673,682
1004,0964,5094,9205,3285,7356,1386,5406,9417,3407,739
2008,1388,5398,9409,3439,74710,15310,56110,97111,38211,795
30012,20912,62413,04013,45713,87414,29314,71315,13315,55415,975
40016,39716,82017,24317,66718,09118,51618,94119,36619,79220,218
50020,64421,07121,49721,92422,35022,77623,20323,62924,05524,480
60024,90525,33025,75526,17926,60227,02527,44727,86928,28928,710
70029,12929,54829,96530,38230,79831,21331,62832,04132,45332,865
80033,27533,68534,09334,50134,90835,31335,71836,12136,52436,925
90037,32637,72538,12438,52238,91839,31439,70840,10140,49440,885
1,00041,27641,66542,05342,44042,82643,21143,59543,97844,35944,740
1,10045,11945,49745,87346,24946,62346,99547,36747,73748,10548,473
1,20048,83849,20249,56549,92650,28650,64451,00051,35551,70852,060
1,30052,41052,75953,10653,45153,79554,13854,47954,819------
J standard
potential
difference
005071,0191,5372,0592,5853,1163,6504,1874,726
1005,2695,8146,3606,9097,4598,0108,5629,1159,66910,224
20010,77911,33411,88912,44513,00013,55514,11014,66515,21915,773
30016,32716,88117,43417,98618,53819,09019,64220,19420,74521,297
40021,84822,40022,95223,50424,05724,61025,16425,72026,27626,834
50027,39327,95328,51629,08029,64730,21630,78831,36231,93932,519
60033,10233,68934,27934,87335,47036,07136,67537,28437,89638,512
70039,13239,75540,38241,01241,64542,28142,91943,55944,20344,848
80045,49446,14146,78647,43148,07448,71549,35349,98950,62251,251
90051,87752,50053,11953,73554,34754,95655,56156,16456,76357,360
1,00057,95358,54559,13459,72160,30760,89061,47362,05462,63463,214
1,10063,79264,37064,94865,52566,10266,67967,25567,83168,40668,980
1,20069,553---------------------------

Reference Temperature Characteristics for Platinum Resistance Thermometers (Ω)

Pt100

JIS C 1604-2013

Temperature
(°C)
-100-0Temperature
(°C)
0100200300400500600700800
060.26100.000100.00138.51175.86212.05247.09280.98313.71345.28375.70
-1056.1996.0910103.90142.29179.53215.61250.53284.30316.92348.38378.68
-2052.1192.1620107.79146.07183.19219.15253.96287.62320.12351.46381.65
-3048.0088.2230111.67149.83186.84222.68257.38290.92323.30354.53384.60
-4043.8884.2740115.54153.58190.47226.21260.78294.21326.48357.59387.55
-5039.7280.3150119.40157.33194.10229.72264.18297.49329.64360.64390.48
-6035.5476.3360123.24161.05197.71233.21267.56300.75332.79363.67---
-7031.3472.3370127.08164.77201.31236.70270.93304.01335.93366.70---
-8027.1068.3380130.90168.48204.90240.18274.29307.25339.06369.71---
-9022.8364.3090134.71172.17208.48243.64277.64310.49342.18372.71---
-10018.5260.26100138.51175.86212.05247.09280.98313.71345.28375.70---

JPt100

JIS C 1604-1997

Temperature
(°C)
-100-0Temperature
(°C)
0100200300400500
059.57100.000100.00139.16177.13213.93249.56284.02
-1055.4496.0210103.97143.01180.86217.54253.06---
-2051.2992.0220107.93146.85184.58221.15256.55---
-3047.1188.0130111.88150.67188.29224.74260.02---
-4042.9183.9940115.81154.49191.99228.32263.49---
-5038.6879.9650119.73158.29195.67231.89266.94---
-6034.4275.9160123.64162.08199.35235.45270.38---
-7030.1271.8570127.54165.86203.01238.99273.80---
-8025.8067.7780131.42169.63206.66242.53277.22---
-9021.4663.6890135.30173.38210.30246.05280.63---
-10017.1459.57100139.16177.13213.93249.56284.02---

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 (such as the K3SC).

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.