YOKOGAWA CM6G User Manual

User ’s Manual

Model CM6G Gas Calorimeter

IM 11R02A01-02E

6th Edition

u Introduction

Thank you for purchasing Model CM6G Gas Calorimeter.

In order to have the product deliver its full capabilities, read this instruction manual thoroughly before you use it.

On how to use the Gas density meter, read the instruction manual which comes with the product.

WARNING

Since the ignition starts until it completes, or right after the ame is extinguished, sample gas mixed with the air will be released from the top of the equipment into the installation space. Even though the sample gas will be diluted su󰀩ciently by the air, great attention should be paid to the

following points if the sample gas contains harmful gases such as CO.

• Conrm that the air is supplied before introducing the sample gas.

• Use the equipment in a well-ventilated environment equipped with a ventilation system.

• Do not expose your face above the top of the calorie detector.

n About This Manual

• This manual should be passed on to the end user so that the user can refer to the manual whenever they need.

• If the product is not used in a manner specied in this manual, the safety of this product may

be impaired.

• The contents of this manual are subject to change without prior notice.

• The contents of this manual shall not be reproduced or copied, in part or in whole,without permission.

• This manual explains the functions contained in this product, but does not warrant that they

are suitable for the particular purpose of the user.

• Every e󰀨ort has been made to ensure accuracy in the preparation of this manual. However, when you realize mistaken expressions or omissions, please contact the nearest Yokogawa Electric representative or sales o󰀩ce.

n Drawing Conventions

Some drawings may be partially emphasized, simplied, or omitted, for the convenience of

description.

n Inspection on delivery

After the delivery, open the product package carefully and inspect for damages caused during the transport. Should there be any damage or breakage on the product, please contact YOKOGAWA

immediately. Retain all the packing materials, containers and boxes that came with the product. After unpacking, make sure the delivered products include all of the component equipment you ordered. When conrming the specications, refer to the model and su󰀩x codes indicated on the

nameplate on the product. The models are indicated on the name plates. Check also those of accessories. For further information, please read subsection 1.2 of this document.

IM 11R02A01-02E 6th Edition :May 10, 2019-00

u Safety Precautions

n Safety,Protection,ModicationoftheProduct

• In order to protect the system controlled by the product and the product itself and ensure safe operation, observe the safety precautions described in this user’s manual. We assume no liability for safety if users fail to observe these instructions when operating the product.

• If this instrument is used in a manner not specied in this user’s manual, the protection

provided by this instrument may be impaired.

• If any protection or safety circuit is required for the system controlled by the product or for

the product itself, prepare it separately.

• Be sure to use the spare parts approved by Yokogawa Electric Corporation (hereafter simply referred to as YOKOGAWA) when replacing parts or consumables.

• Modication of the product is strictly prohibited.

• The following safety symbols are used on the product as well as in this manual.

WARNING

This symbol indicates that an operator must follow the instructions laid out in this manual in order to avoid the risks for the human body and health including risk of injury, electric shock, or fatalities. or the damages to instruments. The manual describes what special care the operator must take to avoid such risks.

CAUTION

This symbol indicates that the operator must refer to the instructions in this manual in order to prevent the operator or instrument from being injured, or damaged.

The following are signal words to be found only in our instruction manuals.

CAUTION

This symbol gives essential information to avoid damages of soft or hardware, or system failure.

NOTE

This symbol indicates information that complements the present topic.

n Warning and Disclaimer

• The product is provided on an “as is” basis. YOKOGAWA shall have neither liability nor responsibility to any person or entity with respect to any direct or indirect loss or damage arising from using the product or any defect of the product that YOKOGAWA can not predict in advance.

n Trademark policy

All company or product and product names mentioned in this document are trade names, trademarks or registered trademarks of their representative companies. In this document, trademarks or trade names are not indicated with TM or ® as trademark symbols.

IM 11R02A01-02E 6th Edition :May 10, 2019-00

u After-sales Warranty

n Do not modify the product.

n Yokogawa warrants the product for the period stated in the pre-purchase quotation Yokogawa

shall conduct dened warranty service based on its standard. When the customer site is located

outside of the service area, a fee for dispatching the maintenance engineer will be charged to the customer.

n During the warranty period, for repair under warranty, carry or send the product to the local

sales representative or service o󰀩ce. Yokogawa will replace or repair any damaged parts and

return the product to you.

• Before returning a product for repair under warranty, provide us with the model name

and serial number and a description of the problem. Any diagrams or data explaining the

problem would also be appreciated.

• If we replace the product with a new one, we won’t provide you with a repair report.

n In the following cases, customer will be charged repair fee regardless of warranty period.

• Failure of components which are out of scope of warranty stated in instruction manual.

• Failure caused by usage of software, hardware or auxiliary equipment, which Yokogawa

Electric did not supply.

• Failure due to improper or insu󰀩cient maintenance by user.

• Failure due to modication, misuse or outside-of-specications operation which Yokogawa

does not authorize.

• Failure or damage caused by relocation of the instrument.

• Failure due to power supply (voltage, frequency) being outside specications or abnormal.

• Failure caused by any usage at location or its maintenance that Yokogawa does not authorize.

• Any damage from re, earthquake, storms and oods, lightning, disturbances, riots, warfare,

radiation and other natural changes.

n Yokogawa does not warrant conformance with the specic application at the user site.

Yokogawa will not bear direct / indirect responsibility for damage due to a specic application.

iii

n Yokogawa Electric will not bear direct / indirect responsibility for any damage an end user might

incur, when the user congures the product into systems or resells the product.

n Maintenance service and supplying repair parts will be covered for ve years after the

production ends. For repair for the product, please contact the nearest sales o󰀩ce described in

this instruction manual.

IM 11R02A01-02E 6th Edition :May 10, 2019-00

Blank Page

Model CM6G Gas Calorimeter

IM 11R02A01-02E 6th Edition

CONTENTS

u Introduction ....................................................................................................i

u Safety Precautions .......................................................................................ii

1. Outline ....................................................................................................... 1-1

1.1 StandardSpecications ................................................................................... 1-1

1.2 ModelandSu󰀩xCodes ...................................................................................1-3

1.3 ..............................................................Standard Systems for Each Application

1-4

1.4 ExternalDimensions ........................................................................................ 1-6

1.5 ....................................................................................Principle of Measurements

1-10

Toc-1

2. Installation, Piping, Wiring ...................................................................... 2-1

2.1 Installations .......................................................................................................2-1

2.2 Externalpiping .................................................................................................. 2-1

2.3 ExternalWirings ................................................................................................ 2-4

3. Construction and Function ..................................................................... 3-1

3.1 Air Pressure Regulating System ..................................................................... 3-1

3.2 Gas Pressure Control Section ......................................................................... 3-1

3.3 Di󰀨erentialPressureDetectionPart ............................................................... 3-4

3.4 Calorie Detector ................................................................................................ 3-5

3.4.1 Burner Unit ......................................................................................... 3-8

3.4.2 High/Low Alarm Action ....................................................................... 3-9

3.4.3 Ignition ............................................................................................... 3-9

3.5 Computing Station .......................................................................................... 3-10

3.5.1 Display ............................................................................................. 3-10

3.5.2 Contents of the Data Display ........................................................... 3-13

3.5.3 Correcting Computation ................................................................... 3-14

3.6 Density Meter ................................................................................................... 3-16

4. Preparation of Operation ......................................................................... 4-1

4.1 Sampling Section (Outside panel) .................................................................. 4-1

4.2 Status of Valves ................................................................................................. 4-1

4.3 Water Supply (For Steel Mill Use) .................................................................... 4-1

4.4 Supply of the Air ................................................................................................ 4-2

4.5 Supply of Power ................................................................................................ 4-2

4.6 TheZeroAdjustmentoftheDi󰀨erentialPressureTransmitter .................... 4-2

4.7 AirDi󰀨erentialPressureAdjustment .............................................................. 4-3

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4.8 Pressure Adjustment of the Gas Line .............................................................4-3

5. Operation ................................................................................................... 5-1

5.1 Start Operation .................................................................................................. 5-1

5.2 Stopping Operations ........................................................................................ 5-2

6. Calibration ................................................................................................. 6-1

6.1 Supply of the Calibration Gas .......................................................................... 6-1

6.1.1 For Town Gas Use .............................................................................6-1

6.1.2 For Steel Mill Use ............................................................................... 6-2

6.2 Span Adjustment of the Calorie Detector.......................................................6-2

6.3 Calibration of the Computing Station ............................................................. 6-4

6.4 Calibration of the Density Meter ...................................................................... 6-4

7. Maintenance .............................................................................................. 7-1

7.1 Daily Check ........................................................................................................ 7-1

7.1.1 Air, Gas Di󰀨erential Pressure Adjustment ......................................... 7-1

7.1.2 Take Out the Water Out of the Drain Pot (Pump for Steel Mill Use) .. 7-1

7.1.3 Take Out the Drain from the Air Set ................................................... 7-1

7.2 Regular Check ................................................................................................... 7-2

7.2.1 Cleaning of the Orice Plate and Replacement of O-ring .................7-2

7.2.2 Fulo Filter (For Steel Mill Use)..........................................................7-3

7.2.3 Line Filter (For Town Gas Use) .......................................................... 7-3

7.2.4 Washing Bubbler or Pressure Regulating Pot ................................... 7-4

7.2.5 Dehumidier (For Steel Mill Use) ....................................................... 7-4

7.2.6 Density Meter ..................................................................................... 7-4

7.3 Check at the Regular Service .......................................................................... 7-5

7.3.1 Check the Burner Flame .................................................................... 7-5

7.3.2 Zero Adjustment of the Di󰀨erential Pressure Transmitter .................. 7-6

7.3.3 Others ................................................................................................ 7-6

8. Troubleshooting ....................................................................................... 8-1

8.1 Gas Sampling Pressure Regulating Section ................................................. 8-1

8.2 Air Pressure Adjustment Section ....................................................................8-2

8.3 Di󰀨erentialPressureTransmitterSection ...................................................... 8-2

8.4 Signal Section ................................................................................................... 8-3

8.5 Computing Station ............................................................................................ 8-5

8.6 Other Troubleshooting ..................................................................................... 8-5

Revision Information ...............................................................................................i

IM 11R02A01-02E 6th Edition :May 10, 2019-00

<1. Outline>

1. Outline

Model CM6G Gas calorimeter measures and controls a caloric value of gases, Wobbe-Index (hereinafter referred to as WI), a theoretical air requirement, and a heat input for various kind of

gas burning furnaces.

It detects a temperature rise of a sample gas, whose pressure is normally controlled, by burning it at a burner through the medium of air.

It picks up the ow rate of the sample gas and the air as the di󰀨erential pressure signal and outputs a signal of WI after compensating calculation of the indication di󰀨erence caused by the ow rate variation.

It also detects density of the sample gas by a density meter, and add to WI signal density

compensation, then, outputs a caloric signal.

1.1 StandardSpecications

EMC : EMC Regulatory Arrangement in Australia and New Zealand Korea Electromagnetic Conformity Standard Class A

A급 기기　(업무용 방송통신기자재) 　이 기기는 업무용(A급) 전자파적합기기로서 판매자 또는 사용자는 이 점을 주의하시기 바라며, 가정외의 지역에서 사용하는 것을 목적으로 합니다.

한국 전자파적합성 기준

1-1

n Town Gas Application

Measurement Object : Measurement and control of WI or the caloric value of fuel gas

Measuring Range : 3 to 62 MJ/Nm

Sample Conditions :

Dust ; 5 mg/Nm Temperature ; 50°C or less Humidity ; dew point of 0°C or less Pressure ; (1) 10 to 20 kPa

Range : Select scale range (Span) :

General Gas ; 30 to 50% of maximum value of the span Butane or Butene + Air ; 20 to 30% of maximum value of the span Propane or Propylene + Air ;25 to 40% of maximum value of the span

Output : 1 to 5 V DC, 4 to 20 mA DC (simultaneously), non-isolated,

load resistance; 750 Ω or less

Alarm Contact Output :

Flame o󰀨 alarm; 100 V AC, 5 A, closed when alarm occurs (resistance

Orice Temperature alarm; 100 V AC, 3 A, closed when alarm occurs

Contact Input : Remote ignition (Custom order); 24 V DC, 0.1A or more

for town gas.

or less

(2) 10 kPa or under: with pump (3) 100 to 600 kPa: with pressure reducing valve

load) when contact is opened, the leakage current is 2 mA or less (100 V AC)

(resistance load)

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Repeatability

Measurement Measuring range (Note 1) Repeatability

Caloric value

MJ/Nm

Note 1: High caloric value means 6.3 MJ/Nm3 or more. Low caloric value means below 6.3 MJ/Nm3.

High caloric value

Low caloric value

High caloric value

Low caloric value

± 0.5% of measured value ± 1.0% of measured value

± 1.0% of measured value ± 1.5% of measured value

Sample Gas Flow Rate : Approx. 10 l/min

Response Time (Note 2):

Max.WImeasured Dead time Response time (63.2%)

50 or more 32 or more, less than 50 13 or more, less than 32 Less than 13

Note 2: Response time varies depending on the WI of a sample gas. This is due to the di󰀨erent sample gas ow rate of the calorimeter. The ow rate is preset depending on the WI of the sample gas to prevent the caloric value at the detector burner from exceeding the upper limit.

Approx. 30 sec or less Approx. 27 sec or less Approx. 23 sec or less Approx. 21 sec or less

Approx. 60 sec or less Approx. 53 sec or less Approx. 47 sec or less Approx. 41 sec or less

Utility :

Instrument Air ; Approx. 50 Nl/min, pressure 300 to 700 kPa, dew point of 0°C or less Power Supply ; 100 V AC ± 10%, single phase, 50/60 Hz (Note 3), 860 VA max.

Note 3: When you perform a low caloric value measurement, the frequency variation should be within ±0.4%. If the frequency variation

exceeds ±0.4% (especially for exporting overseas), consult with Yokogawa.

1-2

n Steel Mill Application

Measurement Object : Measurement and control of WI or the caloric value of fuel gas for a

Measuring range : 3 to 62 MJ/Nm

Sample Conditions:

Dust; 100 mg/Nm Temperature; 50°C or less

Pressure; (1) 8 to 15 kPa (2) 8 kPa or under: with pump

Range : Select scale range (Span):

General Gas; 30 to 50% of maximum value of the span Butane or Butene + Air; 20 to 30% of maximum value of the span Propane or Propylene + Air; 25 to 40% of maximum value of the span

Output : 1 to 5 V DC, 4 to 20 mA DC (simultaneously), non-isolated, load

resistance 750Ω or less

Alarm Contact Output :

Flame o󰀨 alarm;

Temperature alarm; 100 V AC, 3 A, closed when alarm occurs (resistance load)

Contact Input: Remote ignition (Custom order); 24 V DC, 0.1A or more

Repeatability :

Measurement Measuring range (Note 1) Repeatability

Caloric value

MJ/Nm

steel mill.

High caloric value

Low caloric value

High caloric value

Low caloric value

or less

100 V AC, 5 A, closed when alarm occurs (resistance load) when contact is opened, the leakage current is 2 mA or less (100V AC)

0.5% of measured value

1.0% of measured value

1.5% of measured value

Note 1: High caloric value means 6.3 MJ/Nm3 or more. Low caloric value means below 6.3 MJ/Nm3.

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Sample Gas Flow Rate :Approx. 10 l/min.

Response Time (Note 2):

Max.WImeasured Dead time Response time (63.2%)

50 or more 32 or more, less than 50 13 or more, less than 32 Less than 13

42 sec or less 39 sec or less 36 sec or less 30 sec or less

70 sec or less 60 sec or less 50 sec or less 45 sec or less

Utility :

Water ; Approx. 0.2 l/min, pressure 200 to 600 kPa Instrument Air ; Approx. 50 Nl/min, pressure 300 to 700 kPa, dew point of 0°C or less Power Supply ; 100 V AC ± 10%, single phase, 50/60 Hz (Note 3), 1100 VA max.

Note 3: In case of low caloric value measurement, frequency variation should be within ± 0.4%. If frequency variation exceeds ± 0.4%,

consult with Yokogawa.

Panel:

Construction : For indoor installation, rack panel

Paint Color: Munsell 3.2PB7.4/1.2 (inside and outside)

Ambient Temperature:

0 to 40°C (little temperature variation,particularly no

rapid change )

1-3

1.2 ModelandSu󰀩xCodes

n CM6G Gas Calorimeter

Model Su󰀩xCode Option Code Description

CM6G

Gas

Pressure

Measurement 00

Power supply -5

Range R - - - - - - - - - - Measuring range

Style *C - - - - - - - - - - Style C

Note: Measuring range and unit must be specied.

- - - - - - - - - - - - - - - - -

-S6 - - - - - - - - - - Always - S6

1 2 3 4 5 6 7 8

-6

- - - - - - - - - - Gas calorimeter

- - - - - - - - - -

Gas pressure 10 to 20 kPa for town gas, quake-proof Gas pressure 10 to 20 kPa for town gas Gas pressure 10 kPa or under for town gas Gas pressure 100 ro 600 kPa for town gas Gas pressure 8 to 15 kPa for steel mill, without preheating Gas pressure 8 to 15 kPa for steel mill, with preheating Gas pressure 8 kPa or under for steel mill, without preheating Gas pressure 8 kPa or under for steel mill, with preheating

WI measurement

Caloric value measurement (GD400G should be purchased

separately)

100 V AC 50 Hz 100 V AC 60 Hz

l Standard Accessories

Followings are the standard accessories supplied.

• Calorie Detector

Name Q’ty Remarks

Mirror Fuse

For burner ame inspection

1 2

3.15 A (A1113EF)

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• Orice Assembly

Name Q’ty Remarks

O-Ring O-Ring

Hexagon Wrench Hexagon Wrench

P16 (Viton) (Y9114XB)

P20 (Silicon) (L9817MT)

Nominal size 1.5 mm

Nominal size 2.5 mm

n Gas Density Meter

Gas Density Meter compensates a density value in caloric value measurement. It is not required for WI measurement.

Converter: GD400G-N-10-N-/PA

Detector: GD300S-J-/KU

Measuring range and unit (specic gravity or density) should be specied. See GS 11T3E1-01E

for further information.

n Option

You must purchase options separately.

Name Part no. Description

Probe H7800HA Insertion length 650 mm

Probe H7800HB Insertion length 1150 mm

Probe H7800HC Insertion length 1650 mm

Fulo lter G7043XJ Element material: Polypropylene

Pressure reducing valve G7008XF Primary pressure: 15 MPa max.

Pore size: 50 μm

Body: SUS 316 Connection: Rc 1/2

Secondary pressure: 0 to 200 kPa

Material: Brass

1-4

1.3 Standard Systems for Each Application

Application Measurement Systemspecication Su󰀩xcode*

Town Gas

Caloric value

MJ/Nm

Steel Mill

Caloric value

MJ/Nm

* The code is basic for gas pressure and measurement.

Note: A wet sample gas in the town gas application is outside the scope of the standard specications. Consult

with Yokogawa.

Without density meter

With density meter

Without density meter

With density meter

Gas pressure 10 to 20 kPa: Standard Gas pressure 10 kPa or under: With pump Gas pressure 100 to 600 kPa: With pressure

reducing value

Gas pressure 10 to 20 kPa: Quake-proof Gas pressure 10 to 20 kPa: Standard Gas pressure 10 kPa or under: With pump Gas pressure 100 to 600 kPa: With pressure

reducing value

Gas pressure 8 to 15 kPa: Without preheating Gas pressure 8 to 15 kPa: With preheating Gas pressure 8 kPa or under: Without preheating Gas pressure 8 kPa or under: With preheating

-S6200

-S6300

-S6400

-S6110

-S6210

-S6310

-S6410

-S6500

-S6600

-S6700

-S6800

-S6510

-S6610

-S6710

-S6810

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n Instructions for System Selection

● The quake-proof type gas calorimeter is always equipped with the density meter.

● The CM6G Gas Calorimeter controls the ow rate under a constant di󰀨erential pressure. In

the caloric value measurement, if the density of a sample gas changes, a ow rate error proportional to the reciprocal of the square root of the density of the sample gas, will be generated, which directly a󰀨ects the caloric value. Therefore, density compensation is required using a density meter.

For the WI measurement, a density meter is not required since the WI is a value

proportional to

1-5

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1.4 ExternalDimensions

n For Town Gas Applications

CM6G-S6200, S6210, S6300, S6310, S6400, S6410

1-6

Unit: mm

Mark Name Connection

A SAMPLE GAS IN Rc1/4

SAMPLE GAS OUT

B C INST.AIR IN 　Rc1/4 D STD.GAS IN 　Rc1/4 E STD.GAS IN 　Rc1/4

B D E

250

View X

130

900

700 550 400

300

OR VENT Rc1/2

740 800

Density meter converter

Computing station

Approx.70

1800100

Approx.1970

100

4-Ø14 holes

* CM6G-S610 (with density meter) only

Density meter detector

700 900

Calorie detector

Flowmeter for density meter

100

Maintenance Space

100

800800 500

900

Back

Front

500

Weight: Approx. 300kg

Dim-6210.ai

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n For Town Gas Application (Quake-proof Type)

CM6G-S6110

1-7

30 640 30

700

Ø120 hole

Density meter converter

1500100

Approx. 1670

400

Computing station

FAIL

---CM6G---

ALM

TREND 3

90.00

18.00

Y2Y1X3X1500.0

35.00

1000.0

37.67

100.00

23.02

▼▼▼

△

▽

0.00

14.65

0.0

23.02

▼ C

SHIFT

<<<

YOKOGAWA◇

1000

4-Ø15 holes

100600

Calorie detector

Flowmeter for density meter

100800100

300700

View X

Mark Name Connection

A SAMPLE GAS IN 　Rc1/4 B INST.AIR IN 　Rc1/4 C1 STD.GAS IN (ZERO) 　Rc1/4 C2 STD.GAS IN (SPAN) 　Rc1/4 D SAMPLE GAS OUT OR VENT 　Rc1/2

Wiring to switch box should be made through the bottom.

Unit: mm

1000 850

Maintenance Space

1000 100500

Back

Front

500

700

800

Weight: Approx. 350kg

Dim-6110.ai

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n For Steel Mill Application

CM6G-S6500, S6510, S6600, S6610, S6700, S6710, S6800, S6810

1-8

Flowmeter for density meter

Calorie detector

Approx.1970

100

Unit: mm

Mark Name Connection A SAMPLE GAS IN Rc1/2 B SAMPLE GAS OUT Rc1/2 C SAMPLE GAS OUT Rc1/2 D STD.GAS IN Rc1/4 E WATER IN Rc1/2 F DRAIN OUT Rc1/2 G INST.AIR IN Rc1/4 H SAMPLE GAS VENT Rc1/4

500

600

700

800

1900

1650 1500

150

750

View X

100

300 200 100 0

Fulflo filter

Dehumidifier

740 30(30)

800

350

Washing bubbler

Drain pot

Pressure regulating pot

Density meter converter

Approx. 70

H B

C A

Pump

Computing station

4-Φ14 holes

80 60

Approx.1160

(100)

* CM6G-S610 (with density meter and flowmeter)

** CM6G-S670, CM6G-S680 (with pump)

Density meter detector

700

900

100

500

800

Maintenance Space

540

900260

Back

Front

500

Weight: Approx. 350kg

Dim-6810.ai

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n Dimensions of Options

l Probe

Unit: mm

Part number L H7800HA Approx. 650 H7800HB Approx. 1150 H7800HC Approx. 1650

)( 350Insertion length L

Φ34

1-9

JIS 10K-80-FF Equiv. SUS304

l FuloFilter(Partno.:G7043XJ)

108

Rc1/2Rc1/2

Approx. 350

Unit: mm

l PressureReducingValve(Partno.:G7008XF)

Secondary pressure gauge

0.3MPaG

Rc1

Primary pressure gauge 25MPaG

H7800HA.ai

Unit: mm

Approx. 119

Approx. 38

Handle for pressure control

Approx. 62

Approx. 120

Outlet

Handle for stop valve

Stop valve

Rc1/4

Outlet

開

閉

Safety valve

Approx. 166

Daiflon packing

W22 Left-hand thread

Inlet

Nut

Approx. 81

F2-8.ai

IM 11R02A01-02E 6th Edition :May 10, 2019-00

<1. Outline>

1.5 Principle of Measurements

The instrument detects the temperature di󰀨erence, using a thermocouple, between the exhaust

combustion gas made after sample gas is burnt in the burner, and the feed air at the inlet of

the burner. Then the instrument amplies the value of temperature di󰀨erence. It adds the compensating calculation to the output signal and measures the caloric value of WI.

1-10

DIFFERENTIAL

PRESSURE

DETECTION

GAS

AIR

Figure 1.1 Measurement principle diagram

BURNING

PRIMARY

MIXING

SECONDARY

TERTIARY

AIR DIVIDING

BLOW

COMPENSATING

CALCULATION

OUTPUT

SIGNAL

When the sample gas is completely burnt by the air, the formula of the increased temperature is as follows:

∆θ = (1.1)

K • Fg

Cps • Fs

where K: Caloric value of the sample gas

Fg: Flow rate of the sample gas

Fs: Air-diluted combustion exhaust gas ow rate

Cps: Constant pressure heat ratio of air-diluted combustion exhaust gas

Air ow rate Fa is big enough compared with the sample gas ow rate Fg (Fa:Fg=50-200:1)

and Cps Cpa, Fs Fa+Fg=Fa ( 1 + g ), therefore, the formula (1.1) is as follows:

∆θ = (1.2)

K • Fg

Cpa • Fa (1 + g)

where Fa: Air ow rate

Cpa: Air constant pressure heat ratio

g: Fg/Fa

When using orice and take out Fa, Fg as a di󰀨erential pressure of before and after orice, Fa

and Fg are represented by the following formula:

Fa = Ka (1.3)

∆ Pa

Fg = Kg

∆ Pg

where: ∆Pa, ∆Pg: Air, gas di󰀨erential pressure between before and after orice

a, ρg: Density of the air and the gas

ka, kg: Orice constant gure of the air and the gas (Orice coe󰀩cient  orice sectional area)

IM 11R02A01-02E 6th Edition :May 10, 2019-00

<1. Outline>

If insert formula (1.3) into formula (1.2), ∆θ is represented by the following formula:

1-11

∆θ = C.K. (1.4)

•

(C =

∆ Pg

∆ Pa

Cpa (1+g)

• • )

According to formula (1.4), if ∆Pa, ∆Pg are constant, temperature di󰀨erence ∆θ is in proportion

to WI (

) or caloric value (K). Thus we can measure continuously WI after ∆θ

measurement, and the caloric value after the measurement and calculation of the density.

IM 11R02A01-02E 6th Edition :May 10, 2019-00

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<2. Installation, Piping, Wiring>

2. Installation, Piping, Wiring

2.1 Installations

Observe the following conditions when you install instruments.

(1) Adequate space for maintenance should be provided around the gas calorimeter.

* See “External Dimention” on 1.4.

(2) The base should be horizontal..

(3) Ambient temperature is 0 to 40°C and no rapid change in ambient temperature is allowed.

*Rapid change here means a change of approximately 10°C within 30 minutes.

(4) Install the instrument in the place where it is not directly exposed to the current of a

conditioned air.

(5) Minimal vibration( If much vibration is unavoidable, take an appropriate measure to absorb

shock, e.g, use of vibration-proof robber).

(6) A ventilation system should be provided.

(7) Corrosive gases and dust are present in small quantities and humidity is low.

(8) The water of the sampling system and the drain line do not freeze up.

2-1

WARNING

From the moment the ignition starts until it completes, or right after the ame extinction, sample gas mixed with the air will be released from the top of the equipment into the installation space of the equipment. Use the equipment in a well ventilated environment equipped with a ventilation

system.

2.2 Externalpiping

Refer to the drawing Figure 1.4. on the connections on the panel

The principal points to be taken care are as follows:

• Bent the outlet of the bent piping as U shape, and prevent it from the rain penetration. Set the outlet at higher position as much as possible where there is little fear of physical danger.

• Drain piping shall be conducted below the level of drain outlet on the panel and conrm no

drain is accumulated on the panel bed.

• It is necessary for the sample line of the instrument for steel mill use to provide a slope of more than 1/3, so that there is no blockade to the gas line by the drain at the bending part of

the piping. Make piping as short as possible. Equip the sample line with thermal insulation

so as to prevent the drain in the pipe line from freezing.

• Locate the standard gas cylinders at the place where they are comparatively cool and not

exposed to direct sunshine.

IM 11R02A01-02E 5th Edition : Dec. 28, 2016-00

+ 45 hidden pages

YOKOGAWA CM6G User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

u Introduction

u Safety Precautions

1. Outline

1.3 Standard Systems for Each Application

1.5 Principle of Measurements

2. Installation, Piping, Wiring

2.1 Installations