FX Series Programmable Controllers jy992d85801a

FX Series Programmable Controllers

USER’S MANUAL

FX2N-2LC Temperature Control Block

• If in doubt about the operation or use of the communication facilities of FX series pleaseconsult the nearest Mitsubisi Electric distributor.

• This manual is subject to change without notice

FX2N-2LC Temperature Control Block

ii

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FX2N-2LC Tempereture Control Block

iv

FX2N-2LC Tempereture Control Block

Guidelines for the Safety of the User and Protection of the Temperature control block FX2N-2LC.

This manual provides information for the use of the Temperature control block FX2N-2LC Themanual has been written to be used by trained and competent personnel The definition ofsuch a person or persons is as follows;

a) Any engineer who is responsible for the planning, design and construction of automaticequipment using the product associated with this manual should be of a competentnature, trained and qualified to the local and national standards required to fulfill thatrole These engineers should be fully aware of all aspects of safety with regards to auto-mated equipment

b) Any commissioning or service engineer must be of a competent nature, trained and ified to the local and national standards required to fulfill that job These engineersshould also be trained in the use and maintenance of the completed product Thisincludes being completely familiar with all associated documentation for the said product.All maintenance should be carried out in accordance with established safety practices.c) All operators of the completed equipment should be trained to use that product in a safeand coordinated manner in compliance to established safety practices The operatorsshould also be familiar with documentation which is connected with the actual operation

qual-of the completed equipment

Note : Note: the term ‘completed equipment’ refers to a third party constructed device which

contains or uses the product associated with this manual

Notes on the Symbols Used in this Manual

At various times through out this manual certain symbols will be used to highlight points ofinformation which are intended to ensure the users personal safety and protect the integrity ofequipment Whenever any of the following symbols are encountered its associated note must

be read and understood Each of the symbols used will now be listed with a brief description ofits meaning

Hardware Warnings

1) Indicates that the identified danger WILL cause physical and property damage.

2) Indicates that the identified danger could POSSIBLY cause physical and property

FX2N-2LC Tempereture Control Block

understand-• Owing to the very great variety in possible application of this equipment, you must satisfyyourself as to its suitability for your specific application

FX2N-2LC Temperature Control Block Contents

4 Wiring 4-1

4.1 Wiring 4-2

5 Introduction of Functions 5-1

5.1 PID control 5-1

5.1.1 Easy PID control with two degrees of freedom 5-1

5.1.2 Overshoot prevention function 5-2

5.4.1 Auto mode and manual mode 5-6

5.4.2 Balance-less, bump-less function 5-7

5.5 Heater disconnection detection function 5-8

5.6 Loop breaking alarm function (LBA) 5-9

6 Alarm 6-1

7 Buffer Memory (BFM) 7-1

7.1 Buffer memory list 7-1

7.2 Details of buffer memories 7-4

7.2.1 BFM #0: Flag 7-4

7.2.2 BFM #1 (CH1) and BFM #2 (CH2): Event 7-5

7.2.3 BFM #3 (CH1) and BFM #4 (CH2): Measured value (PV) 7-7

FX2N-2LC Temperature Control Block Contents

viii

7.2.10 BFM #13 to BFM #16 (CH1) and BFM #22 to BFM #25 (CH2):

Alarm 1/2/3/4 set value 7-8 7.2.11 BFM #17 (CH1) and BFM #26 (CH2): Heater disconnection alarm set value 7-8

7.2.12 BFM #18 (CH1) and BFM #27 (CH2) : Auto/manual mode changeover 7-8

7.2.13 BFM #19 (CH1) and BFM #28 (CH2): Manual output set value 7-9

7.2.14 BFM #20 (CH1) and BFM #29 (CH2): Auto tuning execution command 7-9

7.2.15 BCM#30: Unit type code 7-9

7.2.16 BFM #32 (CH1) and BFM #51 (CH2): Operation mode 7-9

7.2.17 BFM #33 (CH1) and BFM #52 (CH2): Proportional band (P) 7-9

7.2.18 BFM #34 (CH1) and BFM #53 (CH2): Integral time (I) 7-10

7.2.19 BFM #35 (CH1) and BFM #54 (CH2): Derivative time (D) 7-10

7.2.20 BFM #36 (CH1) and BFM #55 (CH2): Control response parameter 7-11

7.2.21 BFM #37 (CH1) and BFM #56 (CH2): Output limiter upper limit

BFM #38 (CH1) and BFM #57 (CH2): Output limiter lower limit 7-12 7.2.22 BFM #39 (CH1) and BFM #58 (CH2): Output change ratio limiter 7-13

7.2.23 BFM #40 (CH1) and BFM #59 (CH2): Sensor correction value setting (PV bias) 7-14

7.2.24 BFM #41 (CH1) and BFM #60 (CH2): Adjustment sensitivity (dead zone) setting 7-15

7.2.25 BFM #42 (CH1) and BFM #61 (CH2): Control output cycle setting 7-15

7.2.26 BFM #43 (CH1) and BFM #62 (CH2): Primary delay digital filter setting 7-16

7.2.27 BFM #44 (CH1) and BFM #63 (CH2): Setting change ratio limiter 7-17

7.2.28 BFM #45 (CH1) and BFM #64 (CH2): AT (auto tuning) bias 7-18

7.2.29 BFM #46 (CH1) and BFM #65 (CH2): Normal/reverse operation selection 7-18

7.2.30 BFM #47 (CH1) and BFM #66 (CH2): Setting limiter upper limit

BFM #48 (CH1) and BFM #67 (CH2): Setting limiter lower limit 7-19 7.2.31 BFM #49 (CH1) and BFM #68 (CH2): Loop breaking alarm judgement time 7-20

7.2.32 In BFM #50, set the loop breaking alarm dead zone of CH1.

In BFM #69, set the loop breaking alarm dead zone of CH2 7-21 7.2.33 BFM #70 (CH1) and BFM #71 (CH2): Input type selection 7-22

7.2.34 BFM #72 to BFM #75: Alarm mode setting 7-23

7.2.35 BFM #76: Alarm 1/2/3/4 dead zone setting 7-25

7.2.36 BFM #77: Number of times of alarm 1/2/3/4 delay 7-26

7.2.37 BFM #78: Number of times of heater disconnection alarm delay 7-26

7.2.38 BFM #79: Temperature rise completion range setting 7-27

7.2.39 BFM #80: Temperature rise completion soak time 7-27

7.2.40 BFM #81: CT monitor method changeover 7-28

7.2.41 BFM #82: Set value range error address 7-28

7.2.42 BFM #83: Set value backup command 7-29

8 Program Example 8-1

8.1 Program example 8-2

9 Diagnostic 9-1

FX2N-2LC Temperature Control Block Introduction 1

FX2N-2LC Temperature Control Block Introduction 1

If a safety circuit is installed inside the PLC, malfunction and erroneous output may cause accidents.

1) Make sure to construct an emergency stop circuit, protection circuit or interlock circuit to prevent damages of a machine, etc outside the PLC or the FX2N-2LC

2) If the PLC or the FX2N-2LC detects an abnormality such as a watch dog timer error or

input value error by the self-diagnosis function or when an abnormality occurs in the I/O control area, etc which cannot be detected by the CPU in the PLC, output control may

be disabled

Design external circuits and structure so that the entire system conservatively operates

in such cases

3) If a failure occurs in a relay, transistor, TRIAC, etc in an output unit of the FX2N-2LC or

the PLC, outputs may keep ON or OFF

For output signals which may lead to severe accidents, design external circuits and ture so that the entire system conservatively operates

struc-Cautions on installation

• Use the unit in the environment for the general specifications described in the manual

Never use the unit in a place with dusts, soot, conductive dusts, corrosive gas or ble gas, place exposed to high temperature, dew condensation or rain and wind or place exposed to vibration or impact

flamma-If the unit is used in such a place, electrical shock, fire, malfunction, damages in the unit

or deterioration of the unit may be caused

• Never drop cutting chips or electric wire chips into the ventilation window of the FX2N

-2LC while drilling screw holes or wiring cables

Such chips may cause fire, failure or malfunction

• After finishing installation, remove a dust preventing sheet adhered on the ventilation

window of the PC and the FX2N-2LC

If the sheet remains attached, fire, failure or malfunction may be caused

• Securely connect cables such as extension cables and memory cassettes to specified

Introduction 1

1-2

1.1 Outline of product

The temperature control block FX2N-2LC (hereafter referred to as "temperature control block"

or "FX2N-2LC") equipped with two temperature input points and two transistor (open collector)output points is a special block to read temperature signals from thermocouples and platinumresistance thermometer bulbs, and perform PID output control

Connect the FX2N-2LC to the FX2N/2NC Series PC

1) As input sensors, two thermocouples, two platinum resistance thermometer bulbs or onethermocouple and one platinum resistance thermometer bulb are available

2) Data can be written and read using FROM/TO instructions when the FX2N-2LC is connected

to the FX2N/2NC Series PC

(The FX2N-2LC performs arithmetic operation for PID control and output control You do nothave to create sequence programs for PID operation.)

3) Disconnection of heaters can be detected by current detection (CT)

4) The proportional band, the integral time and the derivative time can be easily set by autotuning

5) Channels are isolated against each other

FX2N-2LC Temperature Control Block Product Configuration 2

FX2N-2LC Temperature Control Block Product Configuration 2

35 mm)mountinggroove

Connector for next stepextension cable

4

OUT2

24V OUT1

OUT2

24V OUT1

Product Configuration 2

2-2

2.3 Status indication

Table 2.1:

POWER Lit (green) 5 V power is supplied from PC main unit.

Extinguished 5 V power is not supplied from PC main unit.

24V Lit (red) 24 V power is supplied from outside.

Extinguished 24 V power is not supplied from outside.

OUT1 Lit (red) OUT1 output is ON.

Extinguished OUT1 output is OFF.

OUT2 Lit (red) OUT2 output is ON.

Extinguished OUT2 output is OFF.

FX2N-2LC Temperature Control Block Product Configuration 2

2

2.4 Installation method

The FX2N-2LC can be installed on the right side of an FX2N/2NC Series PLC basic unit, FX2N/

2NC Series extension unit or another extension block

The FX2N-2LC can be attached with a DIN rail DIN46277 (width: 35 mm) or directly attached to

a panel surface with screws (M4)

• Installation on DIN rail

Align the upper side of the DIN rail mounting groove of the FX2N-2LC with a DIN railDIN46277 (width: 35 mm) (①), and push the FX2N-2LC on the DIN rail (②)

When removing the FX2N-2LC, pull out downward the DIN rail mounting hook (③), thenremove the FX2N-2LC (④)

• Direct installation on panel surface

Screw-tighten the FX2N-2LC with M4 screws to a panel surface using two (upper and lower)mounting holes provided on the left side of the FX2N-2LC

Assure the interval of 1 to 2 mm between a unit or block installed on the left side of the

FX2N-2LC

Cautions on installation

• Use the unit in the environment for the general specifications described in the manual

Never use the unit in a place with dusts, soot, conductive dusts, corrosive gas or ble gas, place exposed to high temperature, dew condensation or rain and wind or place exposed to vibration or impact

flamma-If the unit is used in such a place, electrical shock, fire, malfunction, damages in the unit

or deterioration of the unit may be caused

• Never drop cutting chips or electric wire chips into the ventilation window of the FX2N

-2LC while drilling screw holes or wiring cables

Such chips may cause fire, failure or malfunction

FX2N-2LC Temperature Control Block Product Configuration 2

2-4

2.5 Connection to PC Main Unit

Connect the FX2N-2LC to the PC main unit with an extension cable

FX2N-2LC units are treated as special blocks of the PLC, and the special block No 0 to 7 isautomatically assigned to each FX2N-2LC unit from the one nearest to the PLC basic unit.(These unit Nos are used in FROM/TO instructions.)

One FX2N-2LC unit occupies eight I/O points in the PC main unit

For the details of I/O assignment in the PC, refer to the manual of the FX2N/2NC Series PC

• Up to eight FX2N-2LC units can be connected to the FX2N Series PC Up to four FX2N-2LCunits can be connected to the FX2NC Series PC

• When connecting the FX2N-2LC unit to the FX2NC Series PC, the interface FX2NC-CNV-IF isrequired

(When connecting the FX2N-2LC unit to the FX2N Series PC, the interface FX2NC-CNV-IF isnot required.)

• For extension, an extension cable FX0N-65EC (650 mm) and the FX2NC-CNV-BC sold rately are required

sepa-Only one FX0N-65EC can be used per system

OUT IN

L N COM24+ X4 X7X10 X13X14X15X16

Y4 Y6 COM3Y10Y12Y1 Y3 Y14

X3 X1

POWER BATT.V RUN

CPU.E PROG.E

POWER

A/D

X0 X5

POWER

0 1 2 3 4 5 6 7

7 4 1

POWER

OUT1 24V OUT2

POWER

OUT1 24V OUT2

FX 2N -32MR

(X020 to X037)

SpecialblockNo.2

( ) indicates the I/O No assignment in the PC main unit

FX2N-2LC Temperature Control Block Specifications 3

FX2N-2LC Temperature Control Block Specifications 3

Driving power supply 24 VDC (-15% to +10%), input from driving power supply terminal

Power supply for

communi-cation 5 VDC (supplied from inside of PC main unit)

Current consumption 24 VDC, 55 mA and 5 VDC, 70 mA

Insulation method

Analog input area and PC are insulated by photocoupler.

Power supply and analog input are insulated by DC/DC converter.

(Channels are not insulated each other.) Number of occupied I/O

points 8 points in total (including input points and output points)

FX2N-2LC Temperature Control Block

Set temperature range Equivalent to input range (Refer to 7.2.33)

Heater disconnection detection Alarm is detected in accordance with setting of buffer memory.

(Variable within range from 0.0 to 100.0 A.).

Operation mode

0: Measured value monitor 1: Measured value monitor + Temperature alarm 2: Measured value monitor + Temperature alarm + Control (Selected by buffer memory)

Self-diagnosis function Adjustment data and input value are checked by watch dog timer.

When abnormality is detected, transistor output turns off.

Memory Built-in EEPROM (Number of times of overwrite: 100,000 times)

Status

indication

POWER Lit (green) 5 V power is supplied from PC main unit.

Extinguished 5 V power is not supplied from PC main unit.

24V Lit (red) 24 V power is supplied from outside.

Extinguished 24 V power is not supplied from outside.

OUT1 Lit (red) OUT1 output is ON.

Extinguished OUT1 output is OFF.

OUT2 Lit (red) OUT2 output is ON.

Extinguished OUT2 output is OFF.

FX2N-2LC Temperature Control Block Specifications 3

Thermocou- ter bulb

32 °F in PLII and WRe5-26 inputs are outside precision antee range.

guar-Cold contact ture compensation error

tempera-Within ± 1.0 °C However, within ± 2.0 °C while input value is -100 to -150 °C within ± 3.0 °C while input value is -150 to -200 °C

resistance 10 Ω or less Operation when input is

disconnected UpscaleOperation when input is

When

CTL-12 is used 0.0 to 100.0 AWhen CTL-

6 is used 0.0 to 30.0 AMeasurement precision Larger one between ± 5 % of input value and 2 A

(excluding precision of current detector) Sampling period 1 second

FX2N-2LC Temperature Control Block Specifications 3

3-4

3.5 Input range

• When B is used, 0 to 399 °C (0 to 799 °F) is outside the precision compensation range

• When PLII is used, 0 to 32 °F is outside the precision compensation range

• When WRe5 to WRe26 are used, 0 to 32 °F is outside the precision compensation range

Table 3.5:

Input range

-200.0 to 200.0 °C -100.0 to 400.0 °C -100 to 1300 °C -100 to 800 °F -100 to 2400 °F

-200.0 to 200.0 °C -100.0 to 400.0 °C -100.0 to 800.0 °C -100 to 1200 °C -100 to 1600 °F -100 to 2100 °F

0 to 400.0 °C -300.0 to 400.0 °F -300.0 to 700.0 °F 0.0 to 700.0 °F

-50.0 to 150.0 °C -200.0 to 600.0 °C -300.0 to 300.0°F -300 to 1100 °F

FX2N-2LC Temperature Control Block Specifications 3

3

3.6 Output specifications

Table 3.6:

Number of output points 2 points

Output method NPN open collector transistor output

Rated load voltage 5 to 24 VDC

Maximum load voltage 30 VDC or less

Maximum load current 100 mA

Leak current in OFF status 0.1 mA or less

Maximum voltage drop in ON status 2.5 V (maximum) or 1.0 V (typical) at 100 mA

Control output cycle 30 seconds (Variable within range from 1 to 100 seconds)

FX2N-2LC Temperature Control Block Specifications 3

3-6

FX2N-2LC Temperature Control Block Wiring 4

FX2N-2LC Temperature Control Block Wiring 4

• As to loads which are dangerous when turning on at the same time, make sure to

inter-lock them outside the PLC and the FX2N-2LC in addition to interlocking of them in a gram in the PLC

pro-• Correctly connect the power cable of the FX2N-2LC and the PLC as described in this

manual

If the AC power supply is connected to a DC I/O terminal or DC power terminal, the PLC may be burnt

• Never perform external wiring to unused terminals in the FX2N-2LC and the PLC

Such wiring may damage the units

• Perform Class 3 grounding with an electric wire of 2 mm2 or more to the grounding nal in the FX2N-2LC and the PLC

termi-However, never perform common grounding with a strong power system

FX2N-2LC Temperature Control Block

Wiring 4

4-2

When a temperature sensor is a thermocouple (TC)

When a temperature sensor is a resistance thermometer bulb (RTD)

*1 Connect the terminal in the FX2N-2LC to the terminal in the PLC to which Class

3 grounding is performed

• When using a thermocouple, use specified compensating lead wires

• When using a resistance thermometer bulb, use the three-wire type, and perform wiringwith lead wires having small resistance and no difference in the resistance among the threewires

• Terminal tightening torque: 0.5 to 0.8 N·m

24+

OUT1 COM OUT2 CT CT PTA / • FG PTB / TC+

24-PTB / CT CT PTA / • FG PTB / TC+

PTB /

TC-SSR SSR

DC24V + -

CT

CT Heater

Heater

Shielded cable

Shielded cable Thermocouple Thermocouple

FX2N-2LC Temperature Control Block Introduction of Functions 5

FX2N-2LC Temperature Control Block Introduction of Functions 5

Introduction of Functions 5

This section introduces the functions of the FX2N-2LC

For setting of each function, refer to the description on buffer memories (BFM) later

5.1 PID control

5.1.1 Easy PID control with two degrees of freedom

PID control is a control method to obtain stable control result by setting each of the constants

"P (proportional band)", "I (integral time)" and "D (derivative time)"

However, if each PID constant is so set that the "response to setting" becomes good, the

"response to disturbance" becomes deteriorated in PID control On the contrary, if each PIDconstant is so set that the "response to disturbance" becomes good, the "response to setting"becomes deteriorated

The FX2N-2LC performs easy PID control with two degrees of freedom in which PID constantsrealizing good response to disturbance are adopted and the shape of the "response to setting"can be selected as either "fast", "medium" or "slow"

Setting of PID constants and selection of the "response to setting" can be performed usingbuffer memories

Conventional PID control

When PID constants are set so that the response to changes in set value becomes good

Response to changes in set value Response to disturbance

Set value

(SV)

Set value (SV)

When PID constants are so set that the response to disturbance becomes good

Response to changes in set value Response to disturbance

Set value

Easy PID control with two degrees of freedom

Response to changes in set value Response to disturbance

Fast Medium FX2N-2LC Temperature Control Block

Introduction of Functions 5

5-2

5.1.2 Overshoot prevention function

Generally in PID control, when a deviation continues for a long time, the PID arithmetic tion result exceeds the effective range (from 0 to 100%) of the operation quantity At this time,even if the deviation becomes smaller, it takes some time until the output comes within theeffective range because of the integral operation As a result, execution of an actual correctionoperation is delayed, and overshoot/undershoot occurs

opera-In order to prevent overshoot, the FX2N-2LC is equipped with the RFB (reset-feedback) limiterfunction The RFB limiter function feeds back the excessive quantity to the integral value andmakes the arithmetic operation result be held at the limit point when the PID arithmetic opera-tion result exceeds the limit point (upper/lower limit of the output limiter) so that the PID arith-metic operation result always remains inside the effective range Accordingly, when a deviationbecomes small, the correction operation is immediately performed

<When the RFB limiter function is not provided>

Operation

quantity (%)

<When the RFB limiter function is provided>

Output limiter upper limit

Output limiter lower limit

Output limiter upper limit

Output limiter lower limit

The excessive quantity above the output limiter upper limit is fed back to the integral value, and the arithmetic operation result is held at the upper limit value.

Temperature

Target value

FX2N-2LC Temperature Control Block Introduction of Functions 5

When the adjustment sensitivity (dead zone) is set, repetitious turning ON/OFF of the outputaround the temperature set value (SV) can be prevented

However, if the adjustment sensitivity (dead zone) is set to a large value, upward/downwardfluctuation becomes large accordingly If the adjustment sensitivity (dead zone) is set to asmall value, chattering (drastic repetitious turning ON/OFF) may be caused by small oscilla-tions of measured values

* The adjustment sensitivity is equally given

to the upper portion and the lower portion

of the temperature set value (SV).

FX2N-2LC Temperature Control Block Introduction of Functions 5

When auto tuning starts, position control is performed using the set value (SV) By position control, the output is forcedly hunted and its amplitude and oscillation cycle are mea-sured PID constants are calculated based on the measured values, and stored in eachparameter When auto tuning normally finishes, control continues with new calculated PIDconstants

two-While auto tuning is performed, b14 of the event (CH1: BFM #1, CH2: BFM #2) is set to "1".For auto tuning, the AT bias can be set

(In order to calculate proper PID constants by auto tuning, set the upper limit of the output iter to 100%, the lower limit of the output limiter to 0%, and the output change ratio limiter func-tion to OFF.)

lim-1) Auto tuning can be performed when the following conditions are satisfied

- The control start/stop status shall be set to "control start"

- The operation mode shall be set to the control "mode 2"

- The auto/manual mode shall be set to "auto"

- The input value (PV) shall be normal

- The upper limit and the lower limit of the output limiter shall not be set to a same value

- The proportional band shall not be set to "0 (two-position operation)"

FX2N-2LC Temperature Control Block Introduction of Functions 5

5

2) When either of the following conditions are given during auto tuning, the operation isaborted

- When the input value (PV) becomes abnormal caused by disconnection, etc

- When the set value (SV) is changed

- When control is stopped, when the operation mode is changed or when the auto/manualmode is set to "manual"

- When the AT bias setting is changed

- When the PV bias setting is changed

- When the digital filter setting is changed

- When the output limiter setting is changed

- When the power is interrupted

- When the AT execution command (CH1: BFM #20, CH2: BFM #29) is set to "0 (AT stop)"

Temperature set value (SV)

FX2N-2LC Temperature Control Block Introduction of Functions 5

5-6

5.4 Auto / manual

5.4.1 Auto mode and manual mode

The mode can be changed over between "auto" and "manual" In the auto mode, the controloutput value (MV) is set to the output quantity automatically calculated in accordance with thetemperature set value (SV) In the manual mode, the control output value (MV) is set to theoutput quantity set arbitrarily and manually

In the manual mode, b13 (manual mode transition completion) of the event (CH1: BFM #1,CH2: BFM #2) becomes "1" to notify the manual mode

0.5 second is required to change over the mode During changeover, the balance-less, less function is actuated

bump-Auto mode

In the auto mode, the measured value (PV) is compared with the temperature set value (SV),and the control output (MV) is given by PID arithmetic operation

This mode is selected when the FX2N-2LC is shipped

In the auto mode, the manual output value is always set to the output value (MV)

Manual mode

In the manual mode, the output (MV) value is fixed to a certain value

By changing the manual output setting (BFM #19, BFM #28), the output value can be fixed to

an arbitrary value

The manual output value can be changed while b13 of the event (CH1: BFM #1, CH2: BFM #2)

is "1" (that is, when the manual mode is selected)

Even in the manual mode, the temperature alarm function is effective