Hitachi EH-150 User Manual 2

HITACHI PROGRAMMABLE CONTROLLER



RESISTANCE TEMPERATURE DETECTIVE

INPUT MODULE(EH-PT4)

APPLICATION MANUAL

NJI-324(X)

WARNING

To ensure that the equipment described by this manual. As well as all equipment connected
to and used with it, operate satisfactorily and safety, all applicable local and national codes
that apply to installing and operating the equipment must be followed. Since codes can vary
geographically and can change with time, it is the user’s responsibility to determine which
standard and codes apply, and to comply with them.

FAILURE TO COMPLY WITH APPLICABLE CODES AND STANDARDS CAN RESULT IN
DAMAGE TO EQUIPMENT AND/OR SERIOUS INJURY TO PERSONNEL.

INSTALL EMARGENCY POWER STOP SWITCH, WHICH OPERATES INDEPENDENTLY OF
THE PROGRAMMABLE CONTROLLER TO PROTECT THE EQUIPMENT AND/OR
PERSONNEL IN CASE OF THE CONTROLLER MALFUNCTION.

Personnel who are to install and operate the equipment should carefully study this manual
and any other referred to by it prior to installation and/or operation of the equipment. Hitachi
Industrial Equipment Systems Co., Ltd. constantly strives to improve its products, and the
equipment and the manual(s) that describe it may be different from those already in your
possession.

If you have any questions regarding the installation and operation of the equipment, or if
more information is desired, contact your local Authorized Distributor or Hitachi Industrial
Equipment Systems Co., Ltd.

IMPORTANT

THIS EQUIPMENT GENERATES, USES, AND CAN RADIATE RADIO FREQUENCY
ENERGY AND, IF NOT INSTALLED AND USED IN ACCORDANCE WITH THE
INSTRUCTION MANUAL, MAY CAUSE INTERFERENCE TO RADIO COMMUNICATIONS.
AS TEMPORARILY PERMITTED BY REGULATION, IT HAS NOT BEEN TESTED FOR
COMPLIANCE WITH THE LIMITS FOR CLASS A COMPUTING DEVICES PURSUANT TO
SUBPART J OF PART 15 OF FCC ROULES, WHICH ARE DESIGNED TO PROVIDE
PEASONABLE PROTECTION AGAINST SUCH INTERFERENCE.

OPERATION OF THIS EQUIPMENT IN A RESIDENTIAL AREA IS LIKELY TO CAUSE
INTERFERENCE IN WHICH CASE THE USER, AT HIS OWN EXPENSE, WILL BE
REQUIRED TO TAKE WHATEVER MEASURES MAY BE REQUIRED TO CORRECT THE
INTERFERENCE.

LIMITED WARRANTY AND IMITATION OF LIABILITY

Hitachi Industrial Equipment Systems Co., Ltd. (Hitachi) warrants to the original purchaser
that the programmable logic controller (PLC) manufactured by Hitachi is free from defects in
material and workmanship under normal use and service. The obligation of Hitachi under this
warranty shall be limited to the repair or exchange of any part or parts which may prove
defective under normal use and service within eighteen (18) months from the date of
manufacture or twelve (12) months from the date of installation by the original purchaser
which ever occurs first, such defect to be disclosed to the satisfaction of Hitachi after
examination by Hitachi of the allegedly defective part or parts. This warranty in expressly in
lieu of all other warranties expressed or implied including the warranties of merchantability
and fitness for use and of all other obligations or liabilities and Hitachi neither assumes, nor
authorizes any other person to assume for Hitachi, any other liability in connection with the
sale of this PLC. This warranty shall not apply to this PLC or any part hereof which has been
subject to accident, negligence, alternation, abuse, or misuse. Hitachi makes no warranty
whatsoever in respect to accessories or parts not supplied by Hitachi. The term “original
purchaser”, as used in this warranty, shall be deemed to mean that person for whom the
PLC in originally installed.

In no event, whether as a result of breach of contract, warranty, tort (including negligence) or
otherwise, shall Hitachi or its suppliers be liable for any special, consequential, incidental or
penal damages including but not limited to, loss or profit or revenues, loss of use of the
products or any associated equipment, damage to associated equipment, cost of capital,
cost of substitute products, facilities, services or replacement power, down time costs, or
claims of original purchaser’s customers for such damages.

To obtain warranty service, return the product to your distributor, or send it with a description
of the problem, proof of purchase, post paid, insured, and in a suitable package to:

Quality Assurance Dept.
Hitachi Industrial Equipment Systems Co., Ltd.
46-1 Ooaza-Tomioka Nakajo-machi
Kitakanbara-gun, Niigata-ken
959-2608 JAPAN

Copyright 2002 by Hitachi Industrial Equipment Systems Co., Ltd.

All Right Reserved – Printed in Japan

The Information and/or drawing set forth in this document and all right in and to
inventions disclosed herein and patent which might be granted thereon disclosing or
employing and the materials, methods, techniques or apparatus described herein
are the exclusive property of Hitachi Industrial Equipment Systems Co., Ltd .

No copies of the information or drawings shall be made without the prior constant of
Hitachi Industrial Equipment Systems Co., Ltd.

Hitachi Industrial Equipment Systems Co., Ltd. provides customer assistance in
varied technical areas. Since Hitachi does not possess full access to data
concerning all of the uses and applications of customer’s products, responsibility is
assumed by Hitachi neither for customer product design nor for any infringement of
patents or rights of others, which may result from Hitachi assistance.

The specifications and descriptions contained in this manual were accurate at the
time they were approved for printing. Since Hitachi Industrial Equipment Systems
Co., Ltd. Incorporated constantly strives to improve all its products, we reserve the
right to make changes to equipment and/or manual at any time without notice and
without incurring any obligation other than as noted in this manual.

Hitachi Industrial Equipment Systems Co., Ltd. assumes no responsibility for errors
that may appear in this manual.

As the product works with user program, and Hitachi Industrial Equipment Systems
Co., Ltd. cannot test all combination of user program components, it is assumed
that a bug or bugs may happen unintentionally. If it is happened: please inform the
fact to Hitachi Industrial Equipment Systems Co., Ltd. or its representative. Hitachi
will try to find the reason as much as possible and inform the countermeasure when
obtained.

Nevertheless Hitachi Industrial Equipment Systems Co., Ltd. intends to make
products with enough reliability, the product has possibility to be damaged at any
time. Therefore personnel who are to install and operate the equipment have to
prepare with the countermeasure such as power off switch can be operated
independently of the controller. Otherwise, it can result in damage to equipment
and/or serious injury to personnel.

Safety Precautions

Read this manual and related documents thoroughly before installing, operating, performing
preventive maintenance or performing inspection, and be sure to use the unit correctly. Use this
product after acquiring adequate knowledge of the unit, all safety information, and all cautionary
information. Also, make sure this manual enters the possession of the chief person in charge of
safety maintenance.
Safety caution items are classified as "Danger" and "Caution" in this document.

DANGER

: Cases where if handled incorrectly a dangerous circumstance may be created, resulting in

possible death or severe injury.

: Cases where if handled incorrectly a dangerous circumstance may be created, resulting

CAUTION

in possible minor to medium injury to the body, or only mechanical damage.

However, depending on the circumstances, items marked with may result in
major
accidents.
In any case, they both contain important information, so please follow them closely.
Icons for prohibited items and required items are shown below:

: Indicates prohibited items (items that may not be performed). For example, when open flames

are prohibited, is shown.

: Indicates required items (items that must be performed). For example, when grounding must

CAUTION

be performed,

is shown.

1. About installation

CAUTION

l Use this product in an environment as described in the catalogue and this document.

If this product is used in an environment subject to high temperature, high humidity, excessive
dust, corrosive gases, vibration or shock, it may result in electric shock, fire or malfunction.

l Perform installation according to this manual.

If installation is not performed adequately, it may result in dropping, malfunction or an
operational error in the unit.

l Do not allow foreign objects such as wire chips to enter the unit.

They may become the cause of fire, malfunction or failure.

2. About wiring

REQUIRED

l Always perform grounding (FE terminal).

If grounding is not performed, there is a risk of electric shocks and malfunctions.

CAUTION

l Connect power supply that meets rating.

If a power supply that does not meet rating is connected, fire may be caused.

l The wiring operation should be performed by a qualified personnel.

If wiring is performed incorrectly, it may result in fire, damage, or electric shock.

3. Precautions when using the unit

DANGER

l Do not touch the terminals while the power is on.

There is risk of electric shock.

l Structure the emergency stop circuit, interlock circuit, etc. outside the programmable controller

(hereinafter referred to as PC).
Damage to the equipment or accidents may occur due to failure of the PC.
However, do not interlock the unit to external load via relay drive power supply of the relay
output module.

CAUTION

l When performing program change, forced output, RUN, STOP, etc., while the unit is running,

be sure to verify safety.
Damage to the equipment or accidents may occur due to operation error.

l Supply power according to the power-up order.

Damage to the equipment or accidents may occur due to malfunctions.

4. About preventive maintenance

DANGER

l Do not connect the , of the battery in reverse. Also, do not charge, disassemble, heat,

place in fire, or short circuit the battery.
There is a risk of explosion or fire.

PROHIBITED

l Do not disassemble or modify the unit.

These actions may result in fire or malfunction.

CAUTION

l Turn off the power supply before removing or attaching module/unit.

Electric shock, malfunction or failure may result.

Revision

No. Content Date ManualNo.

Table of contents

1. Introduction 1-1 to 1-4

1.1 Before Use ･･････････････････････････････････････････････････････････････ 1-2

1.2 Precaution on Use ･･･････････････････････････････････････････････････････1-3

1.3 Features ････････････････････････････････････････････････････････････････ 1-3

1.4 Principle of Operation ･･･････････････････････････････････････････････････1-4

2. Structure and Nameplate 2-1

2.1 Structure and Name of Each Part ･･････････････････････････････････････････2-1

3. Specification 3-1 to 3-2

3.1 Specification list ････････････････････････････････････････････････････････3-1

3.2 Terminal layout and internal circuit･･･････････････････････････････････････ 3-2

4. Block Diagram 4-1

4.1 Internal Block Diagram ･･････････････････････････････････････････････････ 4-1

5. External Wiring 5-1

5.1 Resistance Temperature Detective Connection Method and External Wiring
･････････････････････････････････････････････････････････････････････････5-1

6. Setting 6-1

6.1 Setting of Temperature Range ･･･････････････････････････････････････････ 6-1

7. Collection of Temperature Data 7-1 to 7-7

7.1 I/O Allocation ･･････････････････････････････････････････････････････････7-1

7.2 Temperature Data ･･････････････････････････････････････････････････････ 7-2

7.3 Example of Calculation･･････････････････････････････････････････････････7-4

7.4 Correspondence Table between Temperature and Temperature Data ････････ 7-5

8. Error Detection Processing 8-1 to 8-2

8.1 Measured Temperature Range Over ･･････････････････････････････････････8-1

8.2 Treatment for Sudden Change of Temperature Conversion Data ････････････ 8-2

9. Mounting 9-1 to 9-2

9.1 Installation･････････････････････････････････････････････････････････････9-1

9.2 Mounting Method･･･････････････････････････････････････････････････････9-1

9.3 Maintenance and Inspection ･････････････････････････････････････････････ 9-1

9.4 Precautions on External Wiring･･････････････････････････････････････････9-2

10. Example of Programming 10-1 to 10-4

10.1 Example of Programming 1 ････････････････････････････････････････････10-1

10.2 Example of Programming 2 (Offset adjustment) ･････････････････････････10-4

11. Troubleshooting 11-1

11.1 The Allocation Error “41” is indicated in CPU ･･･････････････････････････11-1

11.2 Data Error in a Specific Channel ･･･････････････････････････････････････11-1

11.3 Data Error in All Channels ････････････････････････････････････････････11-1

12. Appendix 12-1

12.1 Calculation of External Wiring Resistance ･･････････････････････････････12-1

1.Introduction

1. Introduction

This manual describes how to operate the EH-PT4 (Resistance Temperature Detective input
module) properly, which is one of the special function module of EH-150 Programmable Logic
controller(PLC). Carefully read this manual to familiarize yourself with the procedures respectively
of installation, operation, and maintenance and inspection.
Please be sure to read the related application manuals, too.

Table 1.1 Reference Manual list

No. Document Manual No.

1 About the detailed operation method of the programming unit

1) Instruction word programmer (PGM-CHH)
Instruction word programmer manual

2) Portable indication programmer (PGM-GPH)
Portable indication programmer manual

3) LADDER EDITOR FOR WINDOWS (HLW-PC3)
Programming manual

4) LADDER EDITOR FOR DOS (HL-AT3E)
Programming manual

NB981X

NB982X

NJI-206X*

NB335X

*

*

*

2 EH-150 APPLICATION MANUAL NJI-280X*

“*” means revision of manual and up to A, B, C in order.

Reference

What is Resistance Temperature Detective(RTD)?

This is also called as “Resistance Thermometer Sensor”.
Refers to the device measuring the temperature by using the metal’s property that its
electric resistance changes with the temperature and is often made of Pt 100 ohm (platinum
with a resistance of 100 ohm at 0 °C.

As for the principle of the measurement, by feeding a constant current of 1 through 5 mA ( 2
mA in this module) to a resistance temperature detective, the change of resistance due to
that of temperature is measured as the change of voltage.
Use a resistance temperature detective complying with IEC 751 for this module.

1-1

1.Introduction

1.1 Before Use

The resistance temperature detective input module (hear after EH-PT4) has been carefully
manufactured, but you are kindly advised to make the following checks on receipt of it.
(1) The type and specification of the module are as specified by the order.
(2) No damage is caused to the equipment during transport. If any failures is found, contact the sales

office.

(3) The accessories listed in Table 1.2 are supplied.

Table 1.2 Package contents list of resistance temperature detective input module

No. Contents Quantity Remarks

1 Resistance temperature detective input

module body

2 I/O cover 1

3 Operation manual 1

1

1-2

1.Introduction

1.2 Precautions on Use

(1) Before the installation and removal of the module, turn off the power.
(2) Before the connection of the external wiring and removal of the terminal board, turn off the

power.

(3) The terminal board handles fine signals. Therefore upon handling the module or wiring, be

careful not to apply a voltage on it by mistake or leave it under the influence by excessive static
electricity.

(4) Upon the connection of external wiring, before work, eliminate static electricity by touching a

grounded metal bar to prevent it from being damaged by excessive static electricity charged on
the human body. To prevent a malfunction due to static electricity do not touch the terminal
during power feeding.

(5) When the connection cable to a resistance temperature detective is cut, the temperature

conversion data becomes abnormal. If the temperature data exceeds the normal range to protect
the external devices, adjust the control system so that the external devices operate with safety.

(6) If the resistance of a resistance temperature detective (RTD) exceeds 250 ohm (corresponding to

about 410 °C ) at PT100, or 2500 ohm(corresponding to about 410 ºC ) at PT1000, except when
the line is broken, the temperature conversion data is unstable.

1.3 Features

(1) EH-PT4 applies for two kinds of platinum resistance temperature detectives:
Pt100(IEC 751) and Pt1000.
(2) Temperature measurement range: Three kinds of ranges(selected by switch)

Resistance temperature

detectives

Pt100 -50 to + 400 ± 3
Pt100 -20 to + 40 ± 0.5

Pt1000 -50 to + 400 ± 6

(3) Because the accuracy of the temperature measurement range -20 to +40ºC is ± 0.5 ºC, EH-PT4 is

suitable for exact measurement.
(4) Temperature conversion data: signed 15 bits.
(5) Number of Inputs: 4 channels, 3-wire system.

Temperature measurement

range(ºC)

Accuracy(°C)

1-3

2. Structure and Nameplate

4) Setting Switch

3) Terminal Block

単位

：mm

Unit: mm

2. Structure and Nameplate

2.1 Structure and Name of Each Part

Name and function of
each part

1) LockButton



I/Ocover

2)

Type EH-PT4

Weight
Dimensions(mm)

Approx. 180 g

30 95

100

No.

Name

Function Remarks

1) Lock button This is used when removing the module from the
base unit. After it is installed to the base unit, the
fixation can be reinforced using screws. In this
case, use M4x10mm screws.

2) I/O cover This is the cover attached to the terminal block
area.

3) Terminal block

This is the terminal block for connecting input
signals. The terminal block can be connected or
disconnected.

4) Setting Switch This is used for setting of temperature range. Refer chapter 6.

Item Detailed explanation Remarks

Operation explanation

The module receives input signals from outside.
While the module energized,
The CPU module recognizes the status of the loaded
module and when it matches the I/O assignment
information included in the user program. Input
information is received according to the contents of
the user program.

Terminal block The screws for the terminal block are M3 screws.

Use a crimp terminal that fits the screw diameter.
The maximum thickness of the cable should be only
up to 0.75 SQ.
The recommended crimp terminal is indicated
below.

6

2-1

3.Specification

3. Specification

3.1 Specification list

Table 3.1 shows the specifications of EH-PT4.

Table 3.1 Specification

Item Specification

Type EH-PT4
Resistance temperature detective Platinum resistance temperature detective Pt100

(IEC 751)

Platinum resistance temperature detective Pt1000
Temperature conversion data Signed 15 bits (In normal state the lowest bit is always “0”.)
Accuracy -20 to + 40 °C (Pt100) ± 0.5 °C
(Note 1) -50 to + 400 °C (Pt100) ± 3 °C

-50 to + 400 °C (Pt1000) ± 6 °C

Temperature measurement range -20 to +40 °C / -50 to +400 °C

(2mA constant current method)
Number of channels 4 channels
Conversion time About 1s / 4 channels
Insulation Between channel and PC Photocoupler insulation

Between channels Non-insulation
External power supply 24V DC ±10% 100mA max.
Internal current consumption
(5 V DC)
External wiring resistance 400 ohm max. / channel
External wiring Shielded wire
Additional function Linearization
Error detection

-20 to +40 °C (Pt100)

-50 to +400 °C (Pt100/ Pt1000)
Processing for disconnection (Note 2) H7FFF is outputted to channel.

Note 1: The accuracy is the value when 10 minutes pass after the start of power feeding. Just after

power is fed, the value may increase slightly. Because a resistance temperature detective
has an error, confirm it beforehand.

Note 2: This is the case when the current terminal wiring is broken. In case the voltage terminal

wiring is broken, the data becomes unspecified. (“H” of “H7FFF” means the following data is
hexadecimal.)

H7FFF is outputted at –25 °C or less, or at +45 °C or higher

H7FFF is outputted at –60 °C or less, or at +410 °C or higher

200mA max.

3-1

3.Specification

Internal

3.2 Terminal layout and internal circuit

Terminal layout Internal circuit

No. Signal name

1)

2)

3)

4)

5)

6)

7)

8)

9)

10)

11)

12)

13)

14)

15)

16)

17)

18)

1) b0

2) B0

3) b1

4) B1

5) b2

6) B2

7) b3

8) B3

9) 24V DC+

10) A0

11) NC

12) A1

13) NC

14) A2

15) NC

RTD

RTD

A0

B0

b0

A3

B3

b3

24VDC+

24VDC‑

+

Internal current

+

power

circuit

16) A3

17) NC

18) 24V DC-

Note 1) Current terminals and a voltage terminals of unused channels should be wired. By this

wiring read data becomes H7FFF.

3-2

4. Block Diagram

External power

24 V DC+

V/F

Constant

Each

Internal

4. Block Diagram

4.1 Internal Block Diagram

Figure 4.1 shows the internal block diagram.

CPU Bus

Line-

arize

Timing

control

Counter

EH-PT4

conversion

(Note)

Input conversion circuit

Switch circuit

Photocoupler insulation

current

circuit

part

Power

Supply

circuit

External wiring

A0

b0

B0

A3

b3

B3

Shielded
wire

24V DC

24 V DC −

RTD

･･･

RTD

External grounding

Figure 4.1 Internal Block Diagram

Note: V/F conversion refers to the conversion of voltage(V) to frequency(F).

4-1

5. External Wiring

A0

A1NCA2NCA3

24VDC

External wiring(Note1)

A0 to 3 : Current terminal

5. External Wiring

5.1 Resistance Temperature Detective Connection Method and External Wiring

b0

×

RTD

RTD

RTD

Use a shielded cable

×

×

×

×

×

×

×

×

×

B0

×

b1

×

B1

×

b2

×

B2

×

b3

×

B3

×

+24V

×

B0 to 3: Current terminal
b0 to 3: Voltage terminal

NC

Make a short-circuit on
unused channel shown as
the figure.
The temperature data
becomes H7FFF.

NC

-24V

Grounding (Note2)

External power supply

Figure 5.1 External Wiring

Note 1: The external wire length shall be less than 200 m for each channel. In addition, the total

resistance of the wires of each channels to be connected to the current terminals (A0 to A3,
B0 to B3) shall be less than 400 ohm.

Note 2: Use shielded cable and connect shielded to functional earth on the both sides or one side,

which depends on the noise environment.

Note 3: The earth terminal on the power supply module and External power supply 24 VDC must be

connected to the functional earth. When functional earth area doesn't do, temperature data
sometimes become unstable. The data becomes unspecified.

5-1

6. Setting

6. Setting

6.1 Setting of temperature range

This module can be set to three temperature ranges by the dip switch shown in below.

Table 6.1 Temperature rage setting

Temperature

measurement range

Pt100

-20 to +40 °C

Pt100

-50 to +400 °C

Pt1000

-50 to +400 °C

ON

OFF

ON

OFF

ON

OFF

Setting switch

1,2,5 ON

1 2 3 4 5 6 7 8

3,6 ON

1 2 3 4 5 6 7 8

4,7 ON

1 2 3 4 5 6 7 8

Note: Do not use the setting which is not written in the table, because the temperature data

becomes undefined.

Setting switch

(Switch 1)

6-1

7. Collection of Temperature Data

Channel 1 temperature

Channel 2 temperature

Channel 3 temperature

Channel 4 temperature

Slot number

EH-PT4

0 • • • • • • • • • • n

7. Collection of Temperate Data

7. 1 I/O Allocation

The temperature data of each channel is collected in the CPU as the temperature conversion data
corresponding to the temperature.

(1) I/O assignment
The I/O assignment shall be set as “WX4W" by your programming software or the peripheral
equipment.

(2) I/O allocation
Depending on the module installation position, the temperature conversion data is stored in the
word input number shown below.

WX□□n0

1

2
3

conversion data

conversion data

conversion data
conversion data

Figure 7.1

The setting of □□n is determined by the module installation position, as shown below.

AVR CPU

Allocation address WX□n□
Word number (0 to 3)
Slot number (0 to 7)
Unit number (0 to 1)

Figure 7.2

7-1

7. Collection of Temperate Data

b15

b14

b13

b12

b11

b10b9b8b7b5

b6b4b3

b2

b1

b0

-800

400

200

1005025

12.5

6.25

0.781

0.0977

0.0488

7.2 Temperature Data

(1) Content of temperature conversion data [range : -50 to +400 °C] (Pt100/ Pt1000)
The meaning of the each bit( b0 to b15) of temperature conversion data (in WX**) is as shown
below.
The sum of the bit “1” is the measured temperature.

(°C)

0.0244
Note)

<For example>

3.125

1.563

0.195

0.391

(1) HF800 =1111 1000 0000 0000"

(HF) (H8) (H0) (H0)

-800 + 400 + 200 + 100 + 50 = -50 °C
(2) H0600 =0000 0110 0000 0000"

(H0) (H6) (H0) (H0)
25 + 12.5 = 37.5 °C

When an input error occurs( below -51°C and over 410 °C), the temperature conversion data is
H7FFF.
The following relation exits between temperature conversion data and actual temperature.

Temperature (℃) =

Temperature conversion data(signed decimal data)

40.96

Note) “b0” is always “0” in normal time.

Relation between the temperature and temperature conversion data

ａ)Temperature conversion data(hexadecimal) -50 to +400 °C

H4000

H3000
H2000

H1000

H0800

-50
0

50

HF800

100 200

300

400

Temperate(°C)

Figure 7.3

7-2

7. Collection of Temperate

10

(2) Content of temperature conversion data [range : -20 to +40 °C] (Pt100)
The meaning of the each bit( b0 to b15) of temperature conversion data (in WX**) is as shown
below.
The sum of the bit “1” is the measured temperature.

b15 b14 b13 b12 b11 b10 b9 b8 b7 b5b6 b4

-80

40

20

10

5

2.5

1.25

0.3125

0.625

0.78125

0.15625

0.390625

b3 b2

0.1953125

0.0976562

b1 b0

0.0488281

0.024414
Note)

(°C)

<For example>

(1) HE000 = 1110 0000 0000 0000"

(HE) (H0) (H0) (H0)

-800 + 40 + 20 = - 20 °C

(2) H0600 =0000 0110 0000 0000"
(H0) (H6) (H0) (H0)

2.5 + 1.25 = 3.75 ℃
When an input error occurs( below -25°C and over 45°C), the temperature conversion data is
H7FFF.
The following relation exits between temperature conversion data and actual temperature.

Temperature (°C) =

Temperature conversion data(signed decimal data)

409.6

Note) “b0” is always “0” in normal time.

Relation between the temperature and temperature conversion data

b)Temperature conversion data(hexadecimal) -20 to +40 °C

H4000

H3000

H2000

H1000

H0800

-20
0

5

HE000

20

30

40

Temperate (°C)

Figure 7.4

7-3

7. Collection of Temperate Data

7.3 Example of Calculation

The program shown below as an example converts the temperature conversion data in WR0 to
BCD 4 digit data in WM6.
In case the temperature is minus, the bit internal output R0 will be turned on.

EXT (DM000,WR0000) (1)
DM000 = DM000 S* 100 (2)
DM002 = DM000 S/ 4096 (3)
R0 = DM002 S< 0 (4)
ABS (WM004,WM002) (5)
BCD (WM006,WM004) (6)

(1) Because the calculation with sign is that by double words, extend the word temperature

conversion data(WR0) to double word data(stored in DM0).

(2) (3) Calculate by the expression mentioned on previous page. Because the calculation with

decimal point (dividing by 40.96) is not possible, multiply the numerator with 100 (2) and then

divide by 4,096(3).
(4) When the temperature data (result of calculation) is minus, the R0 is turned on.
(5) Turn to an absolute variable (for plus temperature data, use as it is and for minus temperature

data remove the sign to turn it to a plus value.) (Use WM0 because the result of calculation can

be incorporated in a word (less than 16 bits).
(6) WM 4 is converted to BCD 4 digits vaule(WM6).

7-4

7.Collection of Temperature Data

7.4 Correspondence Table between Temperature and Temperature Data

(1)Pt100/Pt1000 -50 to +400 ºC range

Table 7.4.1 Pt100 -50 to +400 ºC range Temperature conversion data

Temperature

( ºC)

Note1)

Decimal

data

Hexadecimal

data

Pt100

resistance

Note 2)

(Ω)

Temperature

( ºC)

Note1)

Decimal

data

Hexadecimal

data

Pt100

resistance

Note 2)

(Ω)

-60 63078 F666 72.33 110 4506 1199 142.29

-55 63283 F733 78.32 120 4915 1333 146.06

-50 63488 F800 80.31 130 5325 14CC 149.82

-45 63693 F8CC 82.29 140 5734 1666 153.58

-40 63898 F999 84.27 150 6144 1800 157.31

-35 64102 FA66 86.25 160 6554 1999 161.04

-30 64307 FB33 88.22 170 6963 1B33 164.76

-25 64512 FC00 90.19 180 7373 1CCC 168.46

-20 64717 FCCC 92.16 190 7782 1E66 172.16

-15 64922 FD99 94.12 200 8192 2000 175.84

-10 65126 FE66 96.09 210 8602 2199 179.51

-5 65331 FF33 98.04 220 9011 2333 183.17
0 0 0000 100.00 230 9421 24CC 186.82
5 205 00CC 101.95 240 9830 2666 190.45

10 410 0199 103.90 250 10240 2800 194.07
15 614 0266 105.85 260 10650 2999 197.69
20 819 0333 107.79 270 11059 2B33 201.29
25 1024 0400 109.73 280 11469 2CCC 204.88
30 1229 04CC 111.67 290 11878 2E66 208.45
35 1434 0599 113.61 300 12288 3000 212.02
40 1638 0666 115.54 310 12698 3199 215.57
45 1843 0733 117.47 320 13107 3333 219.12
50 2048 0800 119.40 330 13517 34CC 222.65
55 2253 08CC 121.32 340 13926 3666 226.17
60 2458 0999 123.24 350 14336 3800 229.67
65 2662 0A66 125.16 360 14746 3999 233.17
70 2867 0B33 127.07 370 15155 3B33 236.65
75 3072 0C00 128.98 380 15565 3CCC 240.13
80 3277 0CCC 130.89 390 15974 3E66 243.59
85 3482 0D99 132.80 400 16384 4000 247.04
90 3686 0E66 134.70 410 16794 4199 250.48
95 3891 0F33 136.60

100 4096 1000 138.50

Note 1) At the range from -50 to +400 ºC of Pt100, the input temperature range is from -50 to +400

ºC. But the temperature data output is from -60 to + 410º C.

Note 2) In case of Pt1000, the resistance is 10 times of PT100.

7-5

7.Collection of Temperature Data
(1)Pt100 -20 to +40℃ range

Table 7.4.2 Pt100 -50 to +40 ºC range Temperature conversion data

Temperature

Note1)

( ºC)

Decimal

data

Hexadecimal

data

Pt100

resistance (Ω)

-25 55296 D800 90.19

-20 57344 E000 92.16

-15 59392 E800 94.12

-10 61440 F000 96.09

-5 63488 F800 98.04
0 0 0000 100.00
5 2048 0800 101.95

10 4096 1000 103.90
15 6144 1800 105.85
20 8192 2000 107.79
25 10240 2800 109.73
30 12288 3000 111.67
35 14336 3800 113.61
40 16384 4000 115.54
45 18432 4800 117.47

Note 1) At the range from -20 to +40 ºC of Pt100, the input temperature input range is from -20 to +40

ºC. But the temperature data output is from -25 to +45 ℃.

7-6

8. Error Deception Processing

M0008 = WM000 <> H0000

8. Error Detection Processing

8.1 Measured Temperature Range over

(1)Interlock
If temperate conversion data is over the measuring range or current terminal wiring is disconnected,
the temperature conversion data becomes H7FFF.
After this data is read, it is necessary to make a program externally for the treatment for an error.
Example of an error detection program

WM000 = H0000

M0008

Yb

M0000 = WX000 == H7FFF
M0001 = WX001 == H7FFF
M0002 = WX002 == H7FFF
M0003 = WX003 == H7FFF

Xa

Yb

The program checks
for error data.

When one error data
is found, M8 is turned
on.

For error data, Yb is
turned on.
Xa is for reset.

Please take a proper countermeasure by using the coil Yb at error detection (M8 ON).
Set the numbers of the sections “a” and “b” corresponding to the actual system.

8-1

8. Error Detection Processing

8.2 Treatment for a Sudden Change of Temperature Conversion Data

When the temperature conversion data is changed suddenly due to the disconnection of external
wiring or influence of noise, the system judges it to be an abnormal condition.
In the example shown below, every scanned data is read in. If a change of 5ºC(Note) or more from the
previously read data is found, the condition is judged to be abnormal and data is aborted.

Note: Change each value to your system.

Example of program

1)

2)

3)

4)

R7E3

WR0008
<
H00CC

WR0009
<
H00CC

WR000A
<
H00CC

DR000 == DX000

DR002 == DX002

DR008 == DR000

DR00A == DR002

WR0008 == WR0008 - WR0000

ABS (WR0008 , WR0008)

WR0009 == WR0009 - WR0001

ABS (WR0009 , WR0009)

WR000A == WR000A - WR0002

ABS (WR000A , WR000A)

WR000B == WR000B - WR0003

ABS (WR000B , WR000B)

WR0010 == WR0000

WR0011 == WR0001

WR0012 == WR0002

Every scanned data is read in and
the data is stored in DR0 and DR2.

For only the initial scanned data,
put the read into the previous
data(DR8 to DRA).

The absolute value of the difference
between the previous data and read
data is calculated.

If the difference between the
previous data and read data is less
than 5ºC, put the read data into
WR10 to WR13. In the following
program, the values of WR10 to
WR13 are treaded a s normal value.

WR000B
<
H00CC

5)

WR0013 == WR0003

DR0008 == DR0010

DR000A == DR0012

Updates the previous data.
When an error occurred, the data is
not updated and instead the previous
data is held.

In the example of this program, no protective action or warning against abnormal data is performed.
Make additional circuits depending on the situation.

8-2

9. Mounting

9. Mounting

9.1 Installation

(1) EH-PT4 module can be installed on both the basic base and expansion base.
(2) Precaution on installation

Upon the installation of the EH-150 series, consider the operability, maintainability and
environment.

(a) For use at proper ambient temperature range

• Secure a sufficient space allowing a good ventilation.

• Do not install the module just over a device generating a great amount of heat(such as heater,
transformer and large capacity resistor).

• If the ambient temperature around the module exceeds 55 °C, set a fan or air conditioner to keep
the temperature below 55 °C.

(b) Do not install the module in panel provided with a high-voltage device.
(c) Keep more than 300 mm away from a high-voltage line and power line.
(d) Installing the basic base 1,000 mm through 1,600 mm from the floor improves the operability.
(e) Secure a clearance of more than 50 mm between the upper and lower sections of the module for

ventilation and maintenance. For the right and left directions, secure a clearance of more than 10
mm.

(f) Never pull out or insert a alive line of the module.

9.2 Mounting Method

(1)Checking a connector
Before and after the installation, check the following two points.
(a) Is there an abnormality on the connector of the basic base or extensive base?
(b) Is there an abnormality in the connector or the module side?
(2)Confirming the external wiring
Before running, confirm the following items:
(a) Check that the connection of the external wiring is proper.
(b) Check that the external wiring terminal board and the module are fastened securely with

screws.

9.3 Maintenance and Inspection

Perform periodic inspection every six months according to the procedure mentioned below.
(1) Remove dust and dirt off the terminal board.
(2) Confirm that the fixing screws of the external wiring terminal board and module are tightened

firmly.

9-1

9. Mounting

9.4 Precautions on External Wiring

Because the external wiring of the EH-PT4 handles fine signals, be sure to use a shielded wire to
suppress the influence of external noise and place the wire separately from the power line and
signal line of different voltage.

Wiring cable (shielded wire) of

300 mm or more

Other signal cables

Other signal cables

Power cable

Note) Weld joints of metallic conduits and ground the welded metallic conduits. (Grounding in accordance with local

legal requirements)

Wiring cable (shielded wire) of

Metallic conduit

Figure. 9.1 Wire Separation by Conduits or Ducts

Caution

Use an external power supply which the over current protection character is as below

Output voltage

Figure. 9.2 Over current protection character

Over current detection

Load current

9-2

10. Example of Programming

12345678ON

OFF

SW1

Temperature at the upper

Temperature at the lower
part of the liquid

Tempera

- Platinum resistance

10. Example of Programming

10.1 Example of Programming 1

(1)Control contents
(a) The program keeps the temperature of a liquid in a bath 10 to 12ºC higher than that of ambient

air temperature.

(b) When the temperature difference between the upper part and the lower part of the liquid is 3ºC

or higher, the program turns a stirrer on.

(c) When the temperature of the liquid exceeds 50 ºC or the temperature difference between the

upper part and the lower part of the liquid exceeds 8 ºC, the program turns a temperature error

lamp on to indicate an error and starts a cooler.
(d) When error data is found, the program turns a data error lamp on and starts the cooler.
(e) When error data is found, the program turns a data error lamp on and starts cooler.
(f) When an error occurs, the program stops a heater.

Air temperature

Motor temperature

part of the liquid

(2) Configuration and allocation

0 1 2 3 4

CPU

AVR

Y16

Motor

Stirrer

Cooler

Heater

Lamp indication

Motor

error

temperature detective
PT100

Figure 10.1 External device

DUM16

DUM16

DUM16

EH-PT4

Install EH-PT4 on the fourth slot.
Use the relay output module installed on
the slot 0 to output to the external device.

-ture

error

Data

error

Y0: Motor
Y1: Cooler
Y2: Heater
Y3: Motor error lamp
Y4: Temperature error lamp
Y5: Data error lamp
WX40: Air temperature
WX41: Temperature at the upper part of the liquid
WX42: Temperature at the lower part of the liquid
WX43: Motor temperature

Basic base

Figure 10.2 PLC configuration

Setting of temperature range
Pt100 , -50 to +400 ºC

10-1

10. Example of Programming

If R0 or R1 turns on, turn the motor for a

The program stores the difference between the

When the temperature at the upper part of

ºC

When the temperature difference is 8ºC

The program stores the absolute

When an error is found, the program

The program stores the temperature

(3)Program

(1)

(2)

(3)

(4)

SS0

DR0000 = DX0040

DR0002 = DX0042

WM0000 = H00000

M0000 = WR0000 == H7FFF

M0001 = WR0001 == H7FFF

M0002 = WR0002 == H7FFF

M0003 = WR0003 == H7FFF

M0004 = WM0000 <> H0000

WR0004 = WR0001 - WR0002

ABS (WR0004 , WR0004)

R0000 = H007C <= WR0004

R0001 = H0148 <= WR0004

data for 4 channels in the internal
output.

Data check

turns M4 on.

value of the temperature difference
between the upper part and the lower

part of the liquid in WR4.

or higher, the program turns R0 on.

(5)

R003 R004

(6)

(7)

(8)

R0001

R002

R0000

R0002 = H1000 <= WR0003

When the motor temperature is 100
or higher, the program turns R2. on

R0003 = H0800 <= WR0001

R0004 = H0800 <= WR0001

the liquid is 50ºC or higher, the program
turns R3 on. When the temperature at the
lower part of the liquid is 50ºC or higher,
the program turns R4 on.

WR0005 = WR0001 - WR0000

R0005 = WR0001 <= WR0000

R0006 = WR0005 <= H0198

R0007 = H01EC <= WR0005

temperature at the upper part of the liquid
and the air temperature in WR5.
When the air temperature is higher than the
temperature at the upper part of the liquid,
the program turns R5 on. When the

temperature difference is 10ºC or lower, the
program turns R6 on. When the temperature

SS0

difference is 10ºC or higher, the program
turns R7 on.

minute.
However, if Y3 turns on, do not turn the

Y0003SS0

Y0000

motor.

(9)

10-2

10.Program

Turn on either R5 or R6 to turn on the

Turn on M4 to light the data

Turn on any one of R1, R3 and R4 to
light the temperature abnormality

Turn on any one of R1, R3, R4, R7 and

When R2 is turned on, the program

R002

(10)

R001

(11)

R003

R004

R007

M004

R001

(12)

R003

R004

Y0003 = 1

Y0004 = 1

Y0002 = 0

Y0001 = 1

turns the motor error lamp on.

M4 to turn on the cooler and turn off
the heater.

lamp.

(13)

(14)

M004

R005

R006

Y0005 = 1

Y0002 = 1

Y0004 = 0

abnormality lamp.

heater and turn off the cooler.

10-3

10. Program

Reference

- side offset

+ side

EH-150

Note: Measure a reference value using a

accuracy than EH-PT4. Or connect a

and obtain a direct offset error. For the

10.2 Example of Programming 2 (Offset adjustment)

The resistance temperature detective itself has an built-in error, therefore an offset error may occur
in temperature conversion data. An offset error occurs due to the change with the passage of time
also. An example of correction by programming in this case is shown below.
However, because an actual offset value is not always a specified value, it cannot be corrected
completely. The offset error refers to the deviation of any temperature conversion data from the
reference value(Note) in a specified rate. (The offset error means the constant deviation from the
reference value.)

Example of offset

Temperature conversion data

offset

A

A

value

temperature
conversion data

measuring device with a higher
resistor with a high accuracy instead

of the resistance temperature device
relationship between the temperature

and resistance, see Table 7.2.

A: Offset error

Temperature(ºC)

(1) Adjustment procedure
(a) Decide whether an offset error is on + or – side toward a reference value.
(b) Obtain a temperature conversion data corresponding to offset error.

Offset error Temperature conversion data

1 ºC H0028 or H002C
2 ºC H0050 or H0054
3 °C H0078 or H007C
4 °C H00A0 or H00A4
5 °C H00CC or H00D0

(c) If offset error is on + side toward the reference value, subtract the value obtained in (b) from

the temperature conversion data. If it is on – side, add the value obtained in (b) to the
temperature conversion data.

(2) Example of programming (The configuration is the same as the example of programming 1)
If the channel 2 has + 2 °C offset, subtract H0050 from the temperature conversion data WX0042.

WR0000 = WX0040
WR0001 = WX0041
WR0002 = WX0042 - H0050
WR0003 = WX0043

10-4

11. Troubleshooting

11 Troubleshooting

If you have some problems, please find the cause according to the following countermeasures. If the
problem is not solved despite this countermeasures, contact the sales office.
If a spare unit is available, replace and see the condition.

11.1 The Allocation Error “41” is indicated in CPU.

Error code “41” is “I/O information verify error”. I/O assignment information and actual loading of
module do not much. (Error codes are output as a hexadecimal to the WRF000.)
(1) Check the I/O assignment in CPU.
(2) Check the connection between the module and base.
(3) A defect may occur from the other modules. Check the other modules. too

11.2 Data Error in a Specific Channel

The type of data errors are (a) unstable data, (b) loss of accuracy and (c) that data is H7FFF.
(1) Check if the wire for the data undergoing an error in its amount is connected properly.
(2) Check if the wiring is placed on the same route as the power line (if so, noise is induced.)
(3) Check if the terminal board screws are tightened securely.
(4) Check if the resistance temperature detective is the PT100/PT1000 complying with IEC 751.
(5) Check if the external wiring resistance (current terminal wiring ) is less than 400 ohm.
(6) Check if a measured temperature is out of the specification rage of EH-PT4.

11.3 Data Error in All Channels

The data of all channels may become H7FFF.
(1) If there is an unused channel, check if its current terminal is correct.
(2) Check the output voltage of external power supply. Check if the wiring of the current terminal is

disconnected.

(3) Check the capacity of the external power supply.(Output current 1A or more)

[Precautions]

(1) Before replacing the module, be certain to turn off the power.
(2) Upon returning a module for a repair, notify us of the details of the abnormal condition.
(3) For troubleshooting, the following tools are necessary.
(a) Phillips screwdriver and slotted screwdriver (+ / -)
(b) Digital multi-meter, circuit tester
(c) Oscilloscope (necessary depending on the case)

11-1

12. Appendix

12. Appendix

12.1 Calculation of External Wiring Resistance

Assuming that the cross section and length of tinned annealed copper wire are S(mm2), and L(m),
the resistance R(Ω) of the wire is
R ≒0.01854×L / S

For example, for a cable whose cross section is 0.18 mm2 and length is 200 m, the resistance is
R ≒0.01854×200 / 0.18 = 20.6 Ω

Because the current terminal of EH-PT4 doubles in both ways, the resistance also doubles

20.6 Ω × 2 = 41.2 Ω.

Because this resistance is the value when the ambient temperature around the wire is 20 °C, if the
ambient temperature is over 20 °C, the resistance rises. The rise per 1 °C is about 0.4%.

In case the ambient temperature is 40 °C, the resistance is
R = 41.2 × (1 + 0.004 × (40 - 20))
≒44.5 Ω

Concerning the details of resistance, investigate individually for each wire. It may be slightly
different from the calculated value.

Reference



In the case of Hitachi twisted shielded cable (CO-DS-IREVV-SX,(10 pairs to 52)), the
maximum conductor resistance in the cross section of 0.18mm2 under the temperature 20 °C is

121.5 ohm/km (according to Hitachi’s Guide Book).

12-1