Fluke 9116A 9116A Manual

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9116A Furnace

Hart Scientific

User's Guide

Rev. 842101

Limited Warranty & Limitation of Liability

Each product from Fluke Corporation, Hart Scientific Division ("Hart") is warranted to be free from de fects in material and workmanship under normal use and service. The warranty period is 1 year for the Furnace. The warranty period begins on the date of the shipment. Parts, product repairs, and services are warranted for 90 days. The warranty extends only to the original buyer or end-user customer of a Hart authorized reseller, and does not apply to fuses, disposable batteries or to any other product, which in Hart's opinion, has been misused, altered, neglected, or damaged by accident or abnormal conditions of operation or handling. Hart warrants that software will operate substantially in accordance with its func tional specifications for 90 days and that it has been properly recorded on non-defective media. Hart does not warrant that software will be error free or operate without interruption. Hart does not warrant calibra tions on the Furnace.

Hart authorized resellers shall extend this warranty on new and unused products to end-user customers only but have no authority to extend a greater or different warranty on behalf of Hart. Warranty support is available if product is purchased through a Hart authorized sales outlet or Buyer has paid the applicable international price. Hart reserves the right to invoice Buyer for importation costs of repairs/replacement parts when product purchased in one country is submitted for repair in another country.

Hart's warranty obligation is limited, at Hart's option, to refund of the purchase price, free of charge re pair, or replacement of a defective product which is returned to a Hart authorized service center within the warranty period.

To obtain warranty service, contact your nearest Hart authorized service center or send the product, with a description of the difficulty, postage, and insurance prepaid (FOB Destination), to the nearest Hart authorized service center. Hart assumes no risk for damage in transit. Following warranty repair, the product will be returned to Buyer, transportation prepaid (FOB Destination). If Hart determines that the failure was caused by misuse, alteration, accident or abnormal condition or operation or handling, Hart will provide an estimate or repair costs and obtain authorization before commencing the work. Following repair, the product will be returned to the Buyer transportation prepaid and the Buyer will be billed for the repair and return transportation charges (FOB Shipping Point).

Rev. 842101

THIS WARRANTY IS BUYER'S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IM PLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. HART SHALL NOT BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL. OR CONSE QUENTIAL DAMAGES OR LOSSES, INCLUDING LOSS OF DATA, WHETHER ARISING FROM BREACH OF WARRANTY OR BASED ON CONTRACT, TORT, RELIANCE OR ANY OTHER THEORY.

Since some countries or states do not allow limitation of the term of an implied warranty, or exclusion or limitation of incidental or consequential damages, the limitations and exclusions of this warranty may not apply to every buyer. If any provision of this Warranty is held invalid or unenforceable by a court of com petent jurisdiction, such holding will not affect the validity or enforceability of any other provision.

Fluke Corporation, Hart Scientific Division

799 E. Utah Valley Drive • American Fork, UT 84003-9775 • USA Phone: +1.801.763.1600 • Telefax: +1.801.763.1010 E-mail: support@hartscientific.com

www.hartscientific.com

1 Before You Start . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2 Symbols Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.3 Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.3.1 WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.3.2 CAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1.4 Authorized Service Centers. . . . . . . . . . . . . . . . . . . . . . 5

2 Specifications and Environmental Conditions . . . . . . . . . . 7

2.1 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.2 Environmental Conditions . . . . . . . . . . . . . . . . . . . . . . 7

3 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.1 Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.2 Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.3 Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.4 Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3.5 Heat Pipe Installation . . . . . . . . . . . . . . . . . . . . . . . . 11

4 Parts and Controls . . . . . . . . . . . . . . . . . . . . . . . . 17

4.1 Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.1.1 Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.2 Furnace Core . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

4.3 Access Well . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

4.4 Back Panel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

5 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5.1 Sodium Heat Pipe Information . . . . . . . . . . . . . . . . . . . 21

5.1.1 Minimum Temperature and Heat-Up Rate . . . . . . . . . . . . . . . . . . . 21

5.1.2 Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

6 Controller Operation . . . . . . . . . . . . . . . . . . . . . . . 23

6.1 Well Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . 23

6.2 Reset Cut-out . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

6.3 Temperature Set-point . . . . . . . . . . . . . . . . . . . . . . . . 25

6.3.1 Programmable Set-points . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

6.3.2 Set-point Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.4 Scan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.4.1 Scan Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.4.2 Scan Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.5 Ramp and Soak Program Menu . . . . . . . . . . . . . . . . . . . 27

6.5.1 Number of Program Set-points . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.5.2 Set-points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.5.3 Program Soak Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.5.4 Program Function Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.5.5 Program Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.6 Secondary Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . 30

6.7 Heater Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

6.8 Proportional Band . . . . . . . . . . . . . . . . . . . . . . . . . . 30

6.9 Cut-out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

6.10 Controller Configuration . . . . . . . . . . . . . . . . . . . . . . 33

6.11 Probe Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 33

6.11.1 R0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

6.11.2 ALPHA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

6.11.3 DELTA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

6.12 Operating Parameters . . . . . . . . . . . . . . . . . . . . . . . . 33

6.12.1 Temperature Scale Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

6.12.2 Cut-out Reset Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

6.12.3 Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

6.12.4 Soak Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

6.13 Serial Interface Parameters . . . . . . . . . . . . . . . . . . . . . 35

6.13.1 Baud Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

6.13.2 Sample Period. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

6.13.3 Duplex Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

6.13.4 Linefeed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

6.14 IEEE-488 Parameters . . . . . . . . . . . . . . . . . . . . . . . . 37

6.14.1 IEEE-488 Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6.14.2 Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6.15 Calibration Parameters . . . . . . . . . . . . . . . . . . . . . . . 38

6.15.1 CTO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

6.15.2 CO and CG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

6.15.3 SCO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

7 Digital Communication Interface . . . . . . . . . . . . . . . . 39

7.1 Serial Communications . . . . . . . . . . . . . . . . . . . . . . . 39

7.1.1 Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

7.1.2 Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

7.1.2.1 Baud Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7.1.2.2 Sample Period. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7.1.2.3 Duplex Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7.1.2.4 Linefeed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7.1.3 Serial Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7.2 IEEE-488 Communication . . . . . . . . . . . . . . . . . . . . . 41

7.2.1 Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

7.2.2 IEEE-488 Interface Address . . . . . . . . . . . . . . . . . . . . . . . . . . 41

7.3 Interface Commands . . . . . . . . . . . . . . . . . . . . . . . . 41

8 Fixed Point Cell Installation Instructions. . . . . . . . . . . . 47

8.1 Installing the Metal Freeze Point Cell. . . . . . . . . . . . . . . . 47

8.2 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

8.3 Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

9 Freeze Point Realization . . . . . . . . . . . . . . . . . . . . . 69

9.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

9.2 How to Realize the Freezing Point of Copper. . . . . . . . . . . . 69

10 Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . 71

10.1 Two Point Calibration Procedure . . . . . . . . . . . . . . . . . . 71

10.1.1 Compute R0& ALPHA: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

10.1.2 Accuracy & Repeatability. . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

11 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

12 Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . 77

12.1 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

iii

Figures and Tables

Table 1 International Electrical Symbols . . . . . . . . . . . . . . . . . . . . . 1

Figure 1. Furnace Core Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 2 HTPRT control probe and cutout thermocouple wire routing and heat pipe

ground wire placement.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 3 Attachment of thermocouples . . . . . . . . . . . . . . . . . . . . . . 15

Figure 4. Front Control Panel (cover door remove) . . . . . . . . . . . . . . . . 17

Figure 5. Back Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Figure 6. Controller Flow Chart . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Table 2. Program mode setting actions . . . . . . . . . . . . . . . . . . . . . . 29

Figure 7. Proportional Band Settings. . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 8. Serial Cable Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Table 3. Digital Interface Command Summary . . . . . . . . . . . . . . . . . . 43

Table 3. Digital Interface Command Summary continued . . . . . . . . . . . . 44

Table 3. Digital Interface Command Summary continued . . . . . . . . . . . . 45

Figure 9. Metal Freeze Point Cell installed in canister . . . . . . . . . . . . . . . 48

Figure 10 Cell supported by stand. . . . . . . . . . . . . . . . . . . . . . . . . . 49

Figure 11 Cotton gloves MUST be used. . . . . . . . . . . . . . . . . . . . . . . 50

Figure 12 Preparing paper towel with reagent grade alcohol. . . . . . . . . . . . 51

Figure 13 Clean cell completely. . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Figure 14 Place insulation in re-entrant well. . . . . . . . . . . . . . . . . . . . . 53

Figure 15 Push insulation to bottom of re-entrant well. . . . . . . . . . . . . . . 54

Figure 16 Clean the basket thoroughly . . . . . . . . . . . . . . . . . . . . . . . 55

Figure 17 Place insulation in cell basket . . . . . . . . . . . . . . . . . . . . . . 56

Figure 18 Insure the insulation is flat at the bottom of the cell basket. . . . . . . . 57

Figure 19 21.6 x 14 cm (5.5 x 8.5 in) paper . . . . . . . . . . . . . . . . . . . . 58

Figure 20 Fiber ceramic paper installation. . . . . . . . . . . . . . . . . . . . . . 59

Figure 21 Insert cell into basket. . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Figure 22 Place fiber ceramic paper in cell basket. . . . . . . . . . . . . . . . . . 61

Figure 23 Fiber ceramic insulation installed on top of cell.. . . . . . . . . . . . . 62

Figure 24 Fiber ceramic paper pushed below cell basket top. . . . . . . . . . . . 62

Figure 25 Preparing basket assembly for installation in furnace. . . . . . . . . . . 63

Figure 26 Installing basket assembly in furnace. . . . . . . . . . . . . . . . . . . 64

Figure 27 Width of insulation placed on top of basket assembly.. . . . . . . . . . 65

Figure 28 Basket, insulation, and furnace lid installed . . . . . . . . . . . . . . . 66

Figure 29 Heat radiation guard installed. . . . . . . . . . . . . . . . . . . . . . . 67

Figure 30. Testing Uniformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

1 Before You Start

1.1 Introduction

The Hart Scientific 9116A Furnace has a temperature range of 550°C to 1100°C and is designed for use in achieving aluminum, silver, or copper freez ing point measurements.

The furnace utilizes a sodium heat pipe to maintain a uniform temperature over the length of the metal freeze point cell. The temperature controller is program mable, a feature that may be conveniently used to simplify the melting, freeze initiation, and plateau control. The temperature control and uniformity of the furnace allows the user to achieve plateaus ranging many hours in length.

1 Before You Start

Introduction

NOTE: Many of the illustrations and examples used in this manual as

sume the use of the copper point cell. Any of the three cells indicated may be used with the appropriate set-points.

1.2 Symbols Used

Table 1 lists the International Electrical Symbols. Some or all of these symbols may be used on the instrument or in this manual.

Tabl e 1 International Electrical Symbols

Symbol Description

AC (Alternating Current)

AC-DC

Battery

CE Complies with European Union Directives

Double Insulated

Electric Shock

9116A Furnace

User’s Guide

Symbol Description

Fuse

PE Ground

Hot Surface (Burn Hazard)

Read the User’s Manual (Important Information)

Off

Canadian Standards Association

OVERVOLTAGE (Installation) CATEGORY II, Pollution Degree 2 per IEC1010-1 refers to the level of Impulse Withstand Voltage protection provided. Equipment of OVERVOLTAGE CATEGORY II is energy-consuming equipment to be supplied from the fixed installation. Examples include household, office, and laboratory appliances.

C-TIC Australian EMC Mark

The European Waste Electrical and Electronic Equipment (WEEE) Directive (2002/96/EC) mark.

1.3 Safety Information

Use this instrument only as specified in this manual. Otherwise, the protection provided by the instrument may be impaired.

The following definitions apply to the terms “Warning” and “Caution”.

•

“WARNING” identifies conditions and actions that may pose hazards to the user.

•

“CAUTION” identifies conditions and actions that may damage the in strument being used.

1.3.1 WARNINGS

To avoid personal injury, follow these guidelines.

•

DO NOT operate this unit without a properly grounded, properly polar ized power cord.

1 Before You Start

Safety Information

DO NOT connect this unit to a non-grounded, non-polarized outlet.

•

DO USE a ground fault interrupt device.

•

HIGH VOLTAGE is used in the operation of this equipment. SEVERE

•

INJURY OR DEATH may result if personnel fail to observe safety pre cautions. Before working inside the equipment, turn power off and dis

connect power cord.

If this equipment is used in a manner not specified by the manufacturer,

•

the protection provided by the equipment may be impaired.

Before initial use, or after transport, or after storage in humid or semi-hu

•

mid environments, or anytime the instrument has not been energized for more than 10 days, the instrument needs to be energized for a "dry-out" period of 2 hours before it can be assumed to meet all of the safety re

quirements of the IEC 1010-1. If the product is wet or has been in a wet environment, take necessary measures to remove moisture prior to apply ing power such as storage in a low humidity temperature chamber operating at 50°C for 4 hours or more.

• This unit contains ceramic fiber or other refractories, which can result in

the following: May be irritating to skin, eyes, and respiratory tract. May be harmful if inhaled. May contain or form cristobalite (crystalline silica) with use at high temperatures (above 1600°F) which can cause severe respiratory disease. Possible cancer hazard based on tests with laboratory animals. Animal studies to date are inconclusive. No human exposure studies with this product have been reported. Service personnel coming into contact with these materials should take proper precautions when handling them. Before maintaining this equipment, read the applicable MSDS (Material Safety Data Sheets).

•

HIGH TEMPERATURES PRESENT in this equipment FIRES AND SEVERE BURNS may result if personnel fail to observe safety precau

tions.

•

DO NOT use this unit for any application other than calibration work.

•

DO NOT use this unit in environments other than those listed in the user's manual.

•

Continuous use of this equipment at high temperatures for extended peri ods of time requires caution.

•

Completely unattended high temperature operation is not recom

mended for safety reasons.

•

In the unlikely event that the heat pipe should leak: DO NOT attempt to put out the fire with water or chemical fire extinguishers. SMOTHER THE FIRE WITH DRY SODA ASH. See the Material Safety Data Sheet (MSDS).

•

Follow all safety guidelines listed in the user’s manual.

9116A Furnace

User’s Guide

1.3.2 CAUTIONS

The furnace generates extreme temperatures. Precautions must be taken to

•

prevent personal injury or damage to objects. Probes may be extremely hot when removed from the furnace. Cautiously handle probes to prevent personal injury. Carefully place probes on a heat resistant surface or rack until they are at room temperature. SPRT’s should be placed in an anneal ing furnace if removed at temperatures greater than 500°C.

Use only grounded AC mains supply of the appropriate voltage to power

•

the instrument. See Section 2.1, Specifications, for power requirements.

The 9116A Furnace utilizes high voltages and currents to create high tem

•

peratures. Caution should always be maintained during installation and use of this instrument to prevent electrical shock and burns. Fire can be a hazard for any device that produces high temperatures. Proper care and installation must be maintained. Responsible use of this instrument will result in safe operation.

Calibration Equipment should only be used by Trained Personnel.

•

To avoid possible damage to the instrument, follow these guidelines.

• Components and heater lifetimes can be shortened by continuous high

temperature operation.

• Operate the instrument in room temperatures as indicated in Section 2.2,

Environmental Conditions. Allow sufficient air circulation by leaving at least 6 inches of space between the furnace and nearby objects. Nothing should be placed over the top of the furnace. The furnace should not be placed under cabinets or tables. Extreme temperatures can be generated out the top of the well. The furnace is equipped with cooling coils, use cold water circulation when the furnace is used above 600°C. (For specif ics see Section 4.5 Plumbing.)

•

The furnace is a precise instrument. Although it has been designed for op timum durability and trouble free operation, it must be handled with care. The instrument should not be operated in wet, oily, dusty or dirty environ ments. Keep the well of the instrument free of any foreign matter. Do not operate near flammable materials.

•

Do not use fluids to clean out the well.

•

If a main supply power fluctuation occurs, immediately turn off the fur nace. Power bumps from brown-outs and black-outs can damage the in strument. Wait until the power has stabilized before re-energizing the furnace.

•

The unit is not equipped with wheels. It is considered to be permanently set once it has been installed. If the unit must be moved for some reason, be sure that the fixed point cell has been removed before moving the fur nace. Any movement of the furnace with the cell inside can damage the cell. The unit is not designed to be lifted or carried. If it must be picked up, it is advisable that two people pick the unit up by placing their hands

1 Before You Start

Authorized Service Centers

under the unit and carefully lifting at the same time. Never move the fur nace if it is hot.

Air circulated through the gap surrounding the furnace core keeps the

•

chassis cool. DO NOT SHUT OFF THE FURNACE WHILE AT HIGH TEMPERATURES. The fan will turn off allowing the chassis to

become hot. Alternatively, if used, the cooling water should remain on un til the furnace is cool.

Once the unit has been taken to high temperatures (over 800°C), it takes

•

days for the unit to cool completely.

1.4 Authorized Service Centers

Please contact one of the following authorized Service Centers to coordinate service on your Hart product:

Fluke Corporation, Hart Scientific Division

799 E. Utah Valley Drive

American Fork, UT 84003-9775

USA

Phone: +1.801.763.1600

Telefax: +1.801.763.1010

E-mail: support@hartscientific.com

Fluke Nederland B.V.

Customer Support Services

Science Park Eindhoven 5108

5692 EC Son

NETHERLANDS

Phone: +31-402-675300

Telefax: +31-402-675321

E-mail: ServiceDesk@fluke.nl

Fluke Int'l Corporation

Service Center - Instrimpex

Room 2301 Sciteck Tower

22 Jianguomenwai Dajie

Chao Yang District

Beijing 100004, PRC

9116A Furnace

User’s Guide

CHINA

Phone: +86-10-6-512-3436

Telefax: +86-10-6-512-3437

E-mail: xingye.han@fluke.com.cn

Fluke South East Asia Pte Ltd.

Fluke ASEAN Regional Office

Service Center

60 Alexandra Terrace #03-16

The Comtech (Lobby D)

118502

SINGAPORE

Phone: +65 6799-5588

Telefax: +65 6799-5588

E-mail: antng@singa.fluke.com

When contacting these Service Centers for support, please have the following

information available:

• Model Number

• Serial Number

• Voltage

•

Complete description of the problem

2 Specifications and Environmental

Conditions

2.1 Specifications

Temperature Range

Accuracy

Stability

Uniformity

Control Probe

Resolution

Readout

Controller

Fault Protection

Cutout Accuracy

Power

Heater

System Fuses

Exterior Dimension

Weight

Safety

550°C to 1100°C (1022°F to 2012°F)

±3.0°C

±0.15°C

±0.05°C

HTPRT

0.1°C/°F below 1000°C/°F 1°C/°F above 1000°C/°F

Switchable °C or °F

Digital controller with data retention

High temperature cutout (Type R cutout thermocouple) Sensor burnout and short protection

±10°C

230 VAC (±10%), 50/60 Hz, 2500 W

2500 W

15 A 250 V fast acting

838 mm H x 610 mm W x 406 mm D (33 x 24 x 16 in)

82 kg (180 lb.)

EN 601010-1, CAN/CSA C22.2 No. 601010.1-04

2.2 Environmental Conditions

Although the instrument has been designed for optimum durability and trou ble-free operation, it must be handled with care. The instrument should not be operated in an excessively dusty or dirty environment. Maintenance and clean ing recommendations can be found in the Maintenance Section of this manual.

The instrument operates safely under the following conditions:

•

ambient temperature range: 5 - 50°C (41 - 122°F)

•

ambient relative humidity: maximum 80% for temperature <31°C, de creasing linearly to 50% at 40°C

•

pressure: 75kPa - 106kPa

•

mains voltage within ± 10% of nominal

vibrations in the calibration environment should be minimized

•

altitude less than 2,000 meters

•

indoor use only

•

If the unit is operating at temperatures above 600°C, cooling coils are accessi ble on the rear of the chassis to prevent the furnace heat from loading down the room air conditioning system. (See Section 3.4 Plumbing)

3 Installation

3.1 Unpacking

Verify that the following components are present:

Furnace

•

Control HTPRT and Cutout Thermocouple

•

Heat Radiation Guard (Quartz tube packed separately)

•

Fixed Point Basket

•

Fixed Point Basket Lid

•

Fixed Point Basket removal tool

•

Sodium Heat Pipe

•

Circular 1.27 cm (0.5 in) fiber ceramic board (already installed in fur

•

nace)

• Top thermal shunt disk

• Bottom thermal shunt disk (already installed in furnace)

• Extra Insulation:

♦

Fiber ceramic insulating paper for the fixed point cell

♦

Small circles for fixed point basket

♦

Miscellaneous for packing around the fixed point cell

♦

Circular 1.27 cm (0.5 in) fiber ceramic board

Unpacking should be done carefully. Several parts are packed disassembled for safe shipment. Small parts may be packed in a separate box inside the crate. Check carefully for all parts. If there is any damage due to shipment, notify your carrier immediately.

3.2 Location

A furnace of this type is typically installed in a calibration laboratory where temperature conditions are generally well controlled. Best results will be ob tained from this type of environment. Avoid the presence of flammable materi als near the furnace. Allow 6 or more inches of air space around the furnace. Adjust the levelers on the bottom of the furnace to level the furnace and to keep it from rocking.

3.3 Power

The 9116A furnace power requirements are listed in Section 2.1 on page 7. The furnace is supplied with a 14-gauge, 2-conductor plus ground cable and con nector. Since building electrical installations may vary, the connector and cable may be removed at the furnace back panel and another used so long as it is

SPRT

Thermal Guard

Assembly

Top Suppor t

Block

Retaining Plate

Top Cover

Cutout Thermocouple

Cooling Coils

Heating Element

Top Thermal Shunt Disk

Control Probe

Metal Freeze Point Cell Basket and Cover

Metal Freeze Point Cell

Heat Pipe

Ceramic Fiber Insulation

Air Gap (Circulating Air)

Bottom Support Block

Bottom Thermal Shunt Disk

Retaining Plate

Top Suppor t Block

1.27 cm Fiber Ceramic Board

Figure 1. Furnace Core Diagram

rated for the specified current and voltage. (See Figure 5, Back Panel on page

19.)

Be sure that the furnace chassis is always solidly grounded. A shock hazard may exist if it is not. All switches are double pole for safety in such hot-hot-neutral installations and both lines are fused.

3.4 Plumbing

The cooling coils are accessible from the back panel of the 9116A chassis (See Figure 5, Back Panel on page 19). The cooling tubes are 6.35 mm (0.25 in) copper. Water cooling prevents much of the furnace heat from loading down air conditioning systems. Provide cold tap water with a valve convenient for opera tion near the rear of the furnace. A flow rate of about 0.4 GPM of tap water is required. Pressure should not exceed 60 PSIG. Drain the warm exit water into an appropriate sump.

3.5 Heat Pipe Installation

NOTE: The first heat of the furnace should be done without the heat pipe to verify operation and to become familiar with the furnace. Remove any packing material before operating.

The heat pipe is shipped separately in order to prevent damage to the heater and delicate fiber ceramic insulation. Re-installation of the control HTPRT and cutout thermocouple is also required. Follow the instructions carefully. Many of the materials are fragile. Refer to Figure 1 on page 10. Should the furnace be relocated, the heat pipe must be removed and reinstalled at the new location. See Figure 1 which shows the internal components of the furnace core.

1. Remove the top cover (1) of the furnace. Remove the metal retaining

plate (2) by detaching the four screws holding it in. Remove the top sup port block (3) and any packing material (used for shipping) from the cen tral furnace core. Leave the bottom support block (4) in place at the bottom of the core.

2. Locate the heat pipe (5) and the heat pipe installation tool. Use cotton gloves to handle the heat pipe. Finger prints will cause corrosion of the Inconel at high temperatures. The installation tool has a handle with heavy gauge wire hooks which fit into the tabs on the top of the furnace. Remove any packing materials from the heat pipe. (Any finger oils must be removed with reagent grade alcohol before installation.) The heat pipe has a protrusion on the top between the installation tabs which served as a filling port. This port must be rotated appropriately to fit the matching notch on the top support block. Note the orientation of the notch on the top support block and be sure to rotate the heat pipe accord ingly. The larger notches in the top support block are toward the rear of the furnace. There is a grounding wire attached to the top flange of the heat pipe. BE CAREFUL that it does not damage the ceramic heaters as the heat pipe is lowered into the furnace.

3. Attach the installation tool to the heat pipe and lower it very carefully into the furnace. Maintain the heat pipe in the center of the well so as to allow the bottom support block to slide into the cavity at the bottom of the heat pipe. The fiber-ceramic material is very fragile. The heater and the support can easily be damaged if care is not taken during heat pipe installation.

4. Once the heat pipe is in place, position the top support block (3) over the heat pipe. Be careful to position the notch onto the heat pipe, the flanges of the heat pipe (5) into the slits in the support block and the grounding wire through the right rear access notch (when facing the furnace) in the support block. If necessary, use a knife to cut pieces of the ceramic blanket material provided to center and firmly locate the top support block in place.

5. Re-attach the metal retaining plate (2) using the four screws. The ground wire from the heat pipe must be routed through the right rear access hole in the plate and attached to the closest screw using two star washers and a screw. Make sure that the ground wire is securely attached to the fur

nace chassis. Check the ground continuity to ensure that the ground wire is intact and the heat pipe (5) is grounded. Insure that the wire routing for the Control (6) and Cutout (7) probe is as shown in Figure 2.

Figure 2 HTPRT control probe and cutout thermocouple wire routing and heat pipe ground wire placement..

6. Reinstall the control HTPRT (6) and the cutout thermocouple (7) as shown in Figure 2 on page 13. They must be inserted far enough to clear the top cover. They should also be centered in the air space between the element and the heat pipe. Small pieces of the fiber ceramic material can be used to fix their positions. The wires from the probes must be prop erly routed and connected to the controller as shown in Figure 2. Re

move the cover over the electronics panel. Route the probe wires through the hole in the top of the furnace (at the front right of the furnace when facing the furnace) and down to the access hole into the electronics com partment (at the center left when facing the electronics panel). Connect the probe wires to the controller. The labels on the probes and the con troller must be used to correctly complete the wiring. The thermocouple wires should be firmly attached using the screw-down terminals on the controller printed circuit board. The HPRT connection must be firmly seated on the controller Make sure that the leads from the thermocouples are directed away from the central well of the furnace, and will not be pinched or interfere with other parts. See Figure 3

7. Reinstall the top cover. Locate the cover over the ball catches and press down firmly.

8. Become familiar with the operation of the furnace before installing the

1 1

1111

11 111

1 1 1

111

11111

111

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1 1 1 1 1 1 111

MH1

MH6

CUTOUT

CONTROL

J10

BLACK - CUTOUT (+)

RED - CUTOUT (-)

White

Green

Red

Black

metal freeze point cell.

Figure 3 Attachment of thermocouples

POWER

SET DOWN

EXIT

9116A

FREEZE POINT FURNACE 550°C to 1000°C

419.03 C

HEATER

MODE

4 Parts and Controls

The 9116A consists of a control panel, furnace core, and a back panel. Each part and control is described below.

4.1 Control Panel

The controls to the furnace are located on panels to the right of the instrument. The upper portion of the panel is sloped and contains the controller which is regularly used during operation of the furnace. An LED on the main display indicates when the controller is sending power to the heater. Red indicates the heater is on, green

4.1.1 Controller

indicates the heater is off, pulsing means the heater power is being regulated by the controller between 0 and 100%.

The controller has overall control of the furnace. This sloped panel is located on the upper right portion of the furnace (see Fig-

ure 4). The controller itself is a hybrid ana-

log/digital device utilizing the high stability of analog circuitry with the flexibility of a micro-processor interface and digital controls.

The following controls and indicators are present on the primary controller panel: (1) the digital LED display, (2) the control but tons, and (3) control indicator LED.

(1) The digital display shows the set and

actual temperatures as well as various other functions, settings and constants. The temperature can be set in scale units of either °C or °F.

(2) The control buttons (SET, DOWN, UP,

and EXIT) are used to set the furnace temperature set-point, access and set other operating and calibration parameters.

Figure 4. Front Control Panel (cover door remove)

A brief description of the functions of the buttons follows:

SET - Used to display the next parameter in a menu and to store parameters to the displayed value.

DOWN - Used to decrement the displayed value of parameters.

UP - Used to increment the displayed value.

EXIT - Used to exit from a menu. When “EXIT” is pressed any changes made

to the displayed value are ignored.

4.2 Furnace Core

The furnace core consists of the heater, insulating materials, heat pipe, heat pipe support blocks, and the housing with water cooling. Refer to Figure 1 on page 10.

The heater is embedded in a fiber ceramic insulating block. A hollow section through the center contains the heat pipe.

The heat pipe is a double wall Inconel cylinder containing sodium. The minimum working temperature of the Sodium heat pipe is about 500°C. The heat pipe must be heated slowly (about 1-2 hours) to this temperature. The temperature may then be raised more quickly to the desired set-point. When the working temperature is achieved, the sodium circulates throughout the tube providing a uniform temperature. The heat pipe has a lifetime of many years. Do not use the heat pipe unnecessarily at high temperatures which reduces the lifetime. Refer to the Section 5 for more information.

CAUTION: In the unlikely event that the heat pipe should leak, do not at-

tempt to put out the fire with water or chemical fire extinguishers. Smother the fire with dry soda ash in accordance with the MSDS sheets at the end of this manual.

The heat pipe is centered in the heating element and supported by means of fi ber ceramic blocks. One block fits into the bottom of the heat pipe and a second fits over the top centering the heat pipe in the heater assembly. The top block also supports the control HTPRT and cutout thermocouple. The heat pipe is shipped separately since its weight would damage the heater and supports if it were in place during shipment.

The entire heater and heat pipe assembly are contained and supported by a sheet metal housing. Copper cooling coils are attached to the outside of this housing. These cooling coils allow some of the heat lost to be removed from the lab area reducing the lab heat load. They are accessible on the rear of the furnace chassis (see Figure 5).

Air is circulated through the gap surrounding the furnace core. This keeps the chassis cool. Do not shut off the furnace while at high temperatures or the fan will turn off allowing the chassis to become hot. Alternatively, if used, the wa ter cooling could remain on until the furnace is cool.

Figure 5. Back Panel

4.3 Access Well

The furnace access well is visible on top of the furnace.

The furnace access well is where the freeze point cell is inserted and removed from the furnace. After a freeze point cell is inserted into the furnace, a thermal shunt disk and thermal guard assembly are installed over it. This provides a block to the heat loss from the well and provides more temperature uniformity for the cell.

4.4 Back Panel

The back panel consists of an exhaust fan, a serial communications connector, a power cord, and cooling water ports. See Figure 5 on page 19.

1. The exhaust fan allows air circulation around the electrical components. Be sure to keep this fan free of foreign objects that could hinder air flow.

2. The serial communication connector is a DB-9 connector for interfacing the furnace to a computer or terminal with serial RS-232 communica tions. (See Section 7 starting on page 39 for details.)

3. The power cord is a non-removable cord.

4. The cooling water ports are provided for connecting to cooling water to reduce the heat load. See Section 4.5 Plumbing for details.

5 General

5.1 Sodium Heat Pipe Information

5.1.1 Minimum Temperature and Heat-Up Rate

The heat pipe should not be inserted into a hot furnace. The minimum operat ing temperature is 500°C. The heat pipe should be installed in a cold furnace and heated to the minimum operating temperature over a minimum 1 hour pe riod. Above the minimum operating temperature the heat-up rate is not important.

5.1.2 Safety Precautions

The heat pipe was designed for long-term maintenance free operation. It was performance tested at the factory and in the furnace.

In the event of an accident which results in a rupture of the heat pipe, the small quantity of sodium may burn. DO NOT use water or standard fire extinguishers on sodium fires. (Refer to MSDS) Standard commercially available materials for extinguishing sodium fires are dry soda ash (Na ite. A container of one of these products should be kept in the laboratory near

the furnace in case of an accident.

Mechanical damage to the fill tube may cause in-leakage of air at low temperatures. This will evidence itself by cold regions in the heat pipe when at operating temperature. Operation should be discontinued and an Authorized Service Center should be consulted.

)orpowderedgraph-

2CO3

6 Controller Operation

Well Temperature

This chapter discusses in detail how to operate the furnace temperature control ler using the front control panel. Using the front panel key-switches and LED display the user may monitor the well temperature, set the temperature set-point in degrees C or F, monitor the heater output power, adjust the control ler proportional band, set the cut-out set-point, and program the probe calibra tion parameters, operating parameters, serial and IEEE-488 interface configuration, and controller calibration parameters. Operation of the controller functions is summarized in Figure 6.

In the following discussion a solid box around the word SET, UP, EXIT or DOWN indicates the panel button while the dotted box indicates the display reading. Explanation of the button or display reading are to the right of each button or display value.

6.1 Well Temperature

The digital LED display on the front panel allows direct viewing of the actual well temperature. This temperature value is what is normally shown on the display. The units, C or F, of the temperature value are displayed at the right. For example,

100.00 C Well temperature in degrees Celsius

The temperature display function may be accessed from any other function by pressing the “EXIT” button.

6.2 Reset Cut-out

If the over-temperature cut-out has been triggered, the temperature display al ternately flashes,

Cut-out Indicates cut-out condition

This message continues to flash until the temperature is reduced and the cut-out is reset.

The cut-out has two modes — automatic reset and manual reset. The mode de termines how the cut-out is reset which allows the instrument to heat up again. When in automatic mode, the cut-out resets itself as soon as the temperature is lowered below the cut-out set-point. When in manual reset mode the cut-out must be reset by the operator after the temperature falls below the set-point.

When the cut-out is active and the cut-out mode is set to manual (“reset”), the display flashes “cut-out” until the user resets the cut-out. To access the reset

cut-out function press the “SET” button.

9116A Furnace

User’s Guide

Figure 6. Controller Flow Chart

6 Controller Operation

Temperature Set-point

The display indicates the reset function.

Access cut-out reset function

RESET? Cut-out reset function

Press “SET” once more to reset the cut-out.

This also switches the display to the set temperature function. To return to dis playing the temperature press the “EXIT” button. If the cut-out is still in the over-temperature fault condition the display will continue to flash “cut-out”. The well temperature must drop a few degrees below the cut-out set-point be fore the cut-out can be reset.

Reset cut-out

6.3 Temperature Set-point

The temperature set-point can be set to any value within the range and with the resolution as given in the specifications. Be careful not to exceed the safe upper temperature limit of any device inserted into the well. The safety cut-out should be properly adjusted to help prevent this occurrence.

Setting the temperature involves two steps: (1) select the set-point memory and (2) adjust the set-point value.

6.3.1 Programmable Set-points

The controller stores 8 set-point temperatures in memory. The set-points can be quickly recalled to conveniently set the calibrator to a previously programmed temperature set-point. To set the temperature one must first select the set-point memory. This function is accessed from the temperature display function by pressing “SET”. The number of the set-point memory currently being used is shown at the left on the display followed by the current set-point value.

100.00 C Well temperature in degrees Celsius

Access set-point memory

1. 25.00 Set-point memory 1, 25.00°C currently used

To change the set-point memory press “UP” or “DOWN”.

4. 600.0 New set-point memory 4, 600.0°C

Press “SET” to accept the new selection and access the set-point value.

Accept selected set-point memory

9116A Furnace

User’s Guide

6.3.2 Set-point Value

The set-point value may be adjusted after selecting the set-point memory and pressing “SET”. The set-point value is displayed with the units, C or F, at the left.

C 600.00 Set-point 4 value in °C

If the set-point value does not need to be changed, press “EXIT” to resume dis playing the well temperature. Press “UP” or “DOWN” to adjust the set-point value.

C 620.00 New set-point value

When the desired set-point value is reached press “SET” to accept the new value and access the temperature scale units selection. If “EXIT” is pressed, any changes made to the set-point are ignored.

Accept new set-point value

6.4 Scan

The scan rate can be set and enabled so that when the set-point is changed the furnace heats or cools at a specified rate (degrees per minute) until it reaches the new set-point. With the scan disabled the furnace heats or cools at the maximum possible rate.

6.4.1 Scan Control

The scan is controlled with the scan on/off function that appears in the main menu after the set-point function.

ScAn=OFF Scan function off

Press “UP” or “DOWN” to toggle the scan on or off.

ScAn=On Scan function on

Press “SET” to accept the present setting and continue.

Accept scan setting

6.4.2 Scan Rate

The next function in the main menu is the scan rate. The scan rate can be set from .1 to 100 °C/minute. The maximum scan rate, however, is actually limited by the natural heating or cooling rate of the instrument. This is often less than 100 °C/minute, especially when cooling.

6 Controller Operation

Ramp and Soak Program Menu

The scan rate function appears in the main menu after the scan control function. The scan rate units are in degrees per minute, degrees C or F depending on the selected units.

Sr= 10.0 Scan rate in °C/min.

Press“UP”or“DOWN”tochangethescanrate.

Sr= 2.0 New scan rate

Press “SET” to accept the new scan rate and continue.

Accept scan rate

6.5 Ramp and Soak Program Menu

The ramp and soak program feature of the 9114 allows the user to program the furnace to automatically cycle through a number of set-point temperatures, holding at each for a determined length of time. The user can select one of four different cycle functions.

The program parameter menu is accessed by pressing “SET” and then “UP”.

100.00 C Well temperature

S+U

ProG Program menu

Press “SET” to enter the program menu

6.5.1 Number of Program Set-points

The first parameter in the program menu is the number of set-points to cycle through. Up to 8 set-points can be used in a ramp and soak program.

Access program menu

Enter program menu

Pn=8 Number of program set-points

Use the “UP” or “DOWN” buttons to change the number from 2 to 8.

Pn=3 New number of program set-points

Press “SET” to continue. Pressing “EXIT” causes any changes made to the pa rameter to be ignored.

9116A Furnace

User’s Guide

Save new setting

6.5.2 Set-points

The next parameters are the program set-points.

1 25.00 First set-point

Use the “UP” or “DOWN” buttons to select any of the set-points.

3 500.00 Third set-point

Press “SET” to be able to change the set-point.

C 500.00 Set-point value

Use “UP” and “DOWN” to change the set-point value.

C 565.00 New set-point value

Press “SET” to save the new set-point value.

The other set-points can also be set in the same manner. Once the set-points are programmed as desired press “EXIT” to continue.

Continue to next menu function

6.5.3 Program Soak Time

The next parameter in the program menu is the soak time. The soak time is the time, in minutes, that the furnace maintains each of the program set-points after settling before proceeding to the next set-point. The duration is counted from the time the temperature settles to within a specified stability. The stability re quirement can be set in the parameter menu as explained in Section 6.12.4.The default is 0.1°C.

Pt=15 Soak time in minutes

Use the “UP” or “DOWN” buttons to change the time.

Pt=5 New soak time

Press “SET” to continue.

Save new setting

6.5.4 Program Function Mode

6 Controller Operation

Ramp and Soak Program Menu

The next parameter is the program function or cycle mode. There are four pos sible modes that determine whether the program scans up (from set-point 1 to n) only or both up and down (from set-point n to 1), and also whether the pro gram stops after one cycle or repeats the cycle indefinitely. Table 2 below shows the action of each of the four program mode settings.

Pf=1 Program mode

Use the “UP” or “DOWN” buttons to change the mode.

Pf=4 New mode

Press “SET” to continue.

Tabl e 2. Program mode setting actions

Function Action

1 up-stop

2 up-down-stop

3 up-repeat

4 up-down-repeat

Save new setting

6.5.5 Program Control

The final parameter in the program menu is the control parameter. There are three choices to choose from 1) start the program from the beginning, 2) con tinue the program from where it was when it was stopped, or 3) stop the program.

Pr=off Program presently off

Use the “UP” or “DOWN” buttons to change the status.

Pr=StArt Start cycle from beginning

Press “SET” to activate the new program control command and return to the temperature display.

Activate new command

9116A Furnace

User’s Guide

6.6 Secondary Menu

6.7 Heater Power

Functions that are used less often are accessed within the secondary menu. The secondary menu is accessed by pressing “SET” and “EXIT” simultaneously and then releasing. The first function in the secondary menu is the heater power display. (See Figure 6 on page 24.)

The temperature controller controls the temperature of the well by pulsing the heater on and off. The total power being applied to the heater is determined by the duty cycle or the ratio of heater on time to the pulse cycle time. This value may be estimated by watching the red/green control indicator light or read di rectly from the digital display. By knowing the amount of heating the user can tell if the calibrator is heating up to the set-point, cooling down, or controlling at a constant temperature. Monitoring the percent heater power lets the user know how stable the well temperature is. With good control stability the per cent heating power should not fluctuate more than ±1% within one minute.

The heater power display is accessed in the secondary menu. Press “SET” and “EXIT” simultaneously and release. The heater power is displayed as a percentage of full power.

100.00 C Well temperature

S+E

Access heater power in secondary menu

12 Pct Heater power in percent

To exit out of the secondary menu press “EXIT”. To continue on to the propor tional band setting function press “SET”.

6.8 Proportional Band

In a proportional controller such as this the heater output power is proportional to the well temperature over a limited range of temperatures around the set-point. This range of temperature is called the proportional band. At the bot tom of the proportional band the heater output is 100%. At the top of the pro portional band the heater output is 0. Thus as the temperature rises the heater power is reduced, which consequently tends to lower the temperature back down. In this way the temperature is maintained at a fairly constant temperature.

The temperature stability of the well and response time depends on the width of the proportional band. See Figure 7. If the band is too wide the well tempera ture deviates excessively from the set-point due to varying external conditions. This is because the power output changes very little with temperature and the

6 Controller Operation

Proportional Band

controller cannot respond very well to changing conditions or noise in the sys tem. If the proportional band is too narrow the temperature may swing back and forth because the controller overreacts to temperature variations. For best control stability the proportional band must be set for the optimum width.

Figure 7. Proportional Band Settings

The proportional bandwidth is set at the factory. Check your Report of Test to verify factory settings. The proportional band width may be altered if the user desires to optimize the control characteristics for a particular application.

The proportional bandwidth is easily adjusted from the front panel. The width may be set to discrete values in degrees C or F depending on the selected units. The proportional band adjustment is accessed within the secondary menu. Press “SET” and “EXIT” to enter the secondary menu and show the heater power. Then press “SET” to access the proportional band.

Access heater power in secondary menu

S+E

12 Pct Heater power in percent

Access proportional band

Pb= 4.01C Proportional band setting

To change the proportional band press “UP” or “DOWN”.

Pb=10.00C New proportional band setting

To accept the new setting and access the cut-out set-point press “SET”. Pressing “EXIT”, exits the secondary menu ignoring any changes just made to the proportional band value.

9116A Furnace

User’s Guide

6.9 Cut-out

As a protection against software or hardware fault, shorted heater triac, or user error, the calibrator is equipped with an adjustable heater cut-out device that shuts off power to the heater if the well temperature exceeds a set value. This protects the instrument and probes from excessive temperatures. The cut-out temperature is programmable by the operator from the front panel of the controller.

If the cut-out is activated because of excessive well temperature, power to the heater shuts off and the instrument cools. The well cools until it reaches a few degrees below the cut-out set-point temperature. At this point the action of the cut-out is determined by the setting of the cut-out mode parameter. The cut-out has two modes — automatic reset or manual reset. If the mode is set to auto matic, the cut-out automatically resets itself when the temperature falls below the reset temperature allowing the well to heat up again. If the mode is set to manual, the heater remains disabled until the user manually resets the cut-out.

The cut-out set-point may be accessed within the secondary menu. Press “SET” and “EXIT” to enter the secondary menu and show the heater power. Then press “SET” twice to access the cut-out set- point.

S+E

Accept the new proportional band setting

Access heater power in secondary menu

12 Pct Heater power in percent

Access proportional band

PB= 4.01C Proportional band setting

Access cut-out set-point

CO= 610C Cut-out set-point

To change the cut-out set-point press “UP” or “DOWN”.

CO= 400C New cut-out set-point

To accept the new cut-out set-point press “SET”.

The next function is the configuration menu. Press “EXIT” to resume display ing the well temperature.

Accept cut-out set-point

6.10 Controller Configuration

6 Controller Operation

Controller Configuration

The controller has a number of configuration and operating options and calibra tion parameters that are programmable via the front panel. These are accessed from the secondary menu after the cut-out set-point function by pressing “SET”. There are 5 sets of configuration parameters — probe parameters, oper ating parameters, serial interface parameters, IEEE-488 interface parameters, and controller calibration parameters. The menus are selected using the “UP” and “DOWN” keys and then pressing “SET”.

6.11 Probe Parameters

The probe parameter menu is indicated by,

PrObE Probe parameters menu

Press “SET” to enter the menu. The probe parameters menu contains the pa rameters, R0, ALPHA, and DELTA, which characterize the resistance-temperature relationship of the platinum control sensor. These parameters may be adjusted to improve the accuracy of the calibrator. This procedure is explained in detail in Section .

The probe parameters are accessed by pressing “SET” after the name of the parameter is displayed. The value of the parameter may be changed using

the “UP” and “DOWN” buttons. After the desired value is reached press “SET” to set the parameter to the new value. Pressing “EXIT” causes the parameter to be skipped ignoring any changes that may have been made.

6.11.1 R0

This probe parameter refers to the resistance of the control probe at 0°C. The value of this parameter is set at the factory for best instrument accuracy.

6.11.2 ALPHA

This probe parameter refers to the average sensitivity of the probe between 0 and 100°C. The value of this parameter is set at the factory for best instrument accuracy.

6.11.3 DELTA

This probe parameter characterizes the curvature of the resistance-temperature relationship of the sensor. The value of this parameter is set at the factory for best instrument accuracy.

6.12 Operating Parameters

The operating parameters menu is indicated by,

9116A Furnace

User’s Guide

6.12.1 Temperature Scale Units

Par Operating parameters menu

Press “UP” to enter the menu. The operating parameters menu contains the units scale setting, cut-out reset mode setting, approach setting, and soak stabil ity setting.

The temperature scale units of the controller may be set by the user to degrees Celsius (°C) or Fahrenheit (°F). The scale is used in displaying the well temper ature, set-point, proportional band, and cut-out set-point.The temperature scale units selection is the first function in the operating parameters menu.

Un=C Scale units currently selected

Press “UP” or “DOWN” to change the units.

Un=F New units selected

Press “SET” to accept the new selection and resume displaying the well temperature.

6.12.2 Cut-out Reset Mode

The cut-out reset mode determines whether the cut-out resets automatically when the well temperature drops to a safe value or whether the operator must manually reset the cut-out.

The parameter is indicated by,

CtorSt Cut-out reset mode parameter

Press “SET” to access the parameter setting. Normally the cut-out is set for manual mode.

Cto=rst Cut-out set for manual reset

To change to automatic reset mode press “UP” and then “SET”.

Cto=Auto Cut-out set for automatic reset

6.12.3 Approach

The approach parameter can be used to reduce overshoot. The larger the value the less overshoot. However, if the value is too large it may take too long for the temperature to settle to a new set-point. The default value is 5. It can be changed in the parameter menu.

6.12.4 Soak Stability

The soak stability controls the required stability of the well temperature for the soak time (see Section 6.5.3). The stability is in degrees Celsius. The default is

0.1°C. This value can be changed in the parameter menu.

6.13 Serial Interface Parameters

The serial RS-232 interface parameters menu is indicated by,

SErIAL Serial RS-232 interface parameters menu

The serial interface parameters menu contains parameters that determine the operation of the serial interface. The parameters in the menu are —BAUD rate, sample period, duplex mode, and linefeed.

6.13.1 Baud Rate

The baud rate is the first parameter in the menu. The baud rate setting determines the serial communications transmission rate.

The baud rate parameter is indicated by,

6 Controller Operation

Serial Interface Parameters

bAUd Serial baud rate parameter

Press “SET” to choose to set the baud rate. The current baud rate value is displayed.

1200 b Current baud rate

The baud rate of the serial communications may be programmed to 300, 600, 1200, or 2400 baud. Use “UP” or “DOWN” to change the baud rate value.

2400 b New baud rate

Press “SET” to set the baud rate to the new value or “EXIT” to abort the opera tion and skip to the next parameter in the menu.

6.13.2 Sample Period

The sample period is the next parameter in the serial interface parameter menu. The sample period is the time period in seconds between temperature measure ments transmitted from the serial interface. If the sample rate is set to 5, the in strument transmits the current measurement over the serial interface approximately every five seconds. The automatic sampling is disabled with a sample period of 0. The sample period is indicated by,

SAMPLE Serial sample period parameter

9116A Furnace

User’s Guide

6.13.3 Duplex Mode

Press “SET” to choose to set the sample period. The current sample period value is displayed.

SA= 1 Current sample period (seconds)

Adjust the value with “UP” or “DOWN” and then use “SET” to set the sample rate to the displayed value.

SA= 60 New sample period

The next parameter is the duplex mode. The duplex mode may be set to full du plex or half duplex. With full duplex any commands received by the calibrator via the serial interface are immediately echoed or transmitted back to the device of origin. With half duplex the commands are executed but not echoed. The du plex mode parameter is indicated by,

DUPL Serial duplex mode parameter

Press “SET” to access the mode setting.

DUP=FULL Current duplex mode setting

The mode may be changed using “UP” or “DOWN” and pressing “SET”.

DUP=HALF New duplex mode setting

6.13.4 Linefeed

The final parameter in the serial interface menu is the linefeed mode. This pa rameter enables (on) or disables (off) transmission of a linefeed character (LF, ASCII 10) after transmission of any carriage-return.

The linefeed parameter is indicated by,

LF Serial linefeed parameter

Press “SET” to access the linefeed parameter.

LF=On Current linefeed setting

The mode may be changed using “UP” or “DOWN” and pressing “SET”.

LF=OFF New linefeed setting

6.14 IEEE-488 Parameters

The calibrator may optionally be fitted with an IEEE-488 GPIB interface. In this case the user may set the interface address and termination within the IEEE-488 parameter menu. This menu does not appear on instruments not fit ted with the interface. The menu is indicated by,

IEEE IEEE-488 parameters menu

Press “SET” to enter the menu.

6.14.1 IEEE-488 Address

6 Controller Operation

IEEE-488 Parameters

The IEEE-488 interface must be configured to use the same address as the ex ternal communicating device. The address is indicated by,

AddrESS IEEE-488 interface address

Press “SET” to access the address setting.

Add=22 Current IEEE-488 interface address

Adjust the value with “UP” or “DOWN” and then use “SET” to set the address to the displayed value.

Add=15 New IEEE-488 interface address

6.14.2 Termination

The transmission termination character can be set to carriage return only, line feed only, or carriage return and linefeed. Regardless of the option selected the instrument will interpret either a carriage return or linefeed as a command ter mination during reception. The termination parameter is indicated with,

EOS IEEE-488 termination

Press “SET” to access the termination setting.

EOS=Cr Present IEEE-488 termination

Use“UP”or“DOWN”tochangetheselection.

EOS=LF New termination selection

Use “SET” to save the new selection.

9116A Furnace

User’s Guide

6.15 Calibration Parameters

6.15.1 CTO

6.15.2 CO and CG

The user has access to a number of the instrument calibration constants namely CTO, C0, and CG. These values are set at the factory and must not be altered. The correct values are important to the accuracy and proper and safe operation of the calibrator. Access to these parameters is available to the user only so that in the event that the controller’s memory fails the user may restore these values to the factory settings. The user should have a list of these constants and their settings with the manual.

The calibration parameters menu is indicated by,

CAL Calibration parameters menu

Press “SET” five times to enter the menu.

Parameter CTO sets the calibration of the over-temperature cut-out. This is not adjustable by software but is adjusted with an internal potentiometer.

These parameters calibrate the accuracy of the temperature set-point. These are programmed at the factory when the instrument is calibrated. Do not alter the value of these parameters. If the user desires to calibrate the instrument for improved accuracy, calibrate R0 and ALPHA according to the procedure given in Section .

6.15.3 SCO

This parameter is used at the factory for testing purposes and SHOULD NOT be altered by the user.

7 Digital Communication Interface

The furnace calibrator is capable of communicating with and being controlled by other equipment through the digital interface. Two types of digital interface are available — the RS-232 serial interface and the optional IEEE-488 GPIB interface.

With a digital interface the instrument may be connected to a computer or other equipment. This allows the user to set the set-point temperature, monitor the temperature, and access any of the other controller functions, all using remote communications equipment.

7.1 Serial Communications

Serial Communications

The calibrator may be installed with an RS-232 serial interface that allows se rial digital communications over fairly long distances. With the serial interface the user may access any of the functions, parameters and settings discussed in Section 6 with the exception of the baud rate setting.

7.1.1 Wiring

The serial communications cable attaches to the calibrator through the DB-9 connector at the back of the instrument. Figure 8 shows the pin-out of this connector and suggested cable wiring. To eliminate noise, the serial cable should be shielded with low resistance between the connector (DB-9) and the shield.

7.1.2 Setup

Before operating the serial in terface, set up the BAUD rate and other configuration param eters. These parameters are programmed within the serial interface menu.

To enter the serial parameter programming mode first press “EXIT” while pressing “SET” and release to enter the second ary menu. Press “SET” repeat edly until the display reads

Figure 8. Serial Cable Wiring

9116A Furnace

User’s Guide

“Probe”. This is the menu selection. Press “UP” repeatedly until the serial in terface menu is indicated with “SERIAL”. Finally press “SET” to enter the se rial parameter menu. In the serial interface parameter menu are the BAUD rate, the sample rate, the duplex mode, and the linefeed parameter.

7.1.2.1 Baud Rate

The baud rate is the first parameter in the menu. The display prompts with the baud rate parameter by showing “baud”. Press “SET” to choose to set the baud rate. The current baud rate value is displayed. The baud rate of the 9114 serial communications may be programmed to 300, 600, 1200, or 2400 baud. The baud rate is pre-programmed to 1200 baud. Use “UP” or “DOWN” to change the baud rate value. Press “SET” to set the baud rate to the new value or “EXIT” to abort the operation and skip to the next parameter in the menu.

7.1.2.2 Sample Period

The sample period is the next parameter in the menu and prompted with “SAM PLE”. The sample period is the time period in seconds between temperature

measurements transmitted from the serial interface. If the sample rate is set to 5 for instance then the instrument transmits the current measurement over the serial interface approximately every five seconds. The automatic sampling is disabled with a sample period of 0. Press “SET” to choose to set the sample period. Adjust the period with “UP” or “DOWN” and then use “SET” to set the sample rate to the displayed value.

7.1.2.3 Duplex Mode

The next parameter is the duplex mode indicated with “dUPL”. The duplex mode may be set to half duplex (“HALF”) or full duplex (“FULL”). With full duplex any commands received by the thermometer via the serial interface are immediately echoed or transmitted back to the device of origin. With half du plex the commands are executed but not echoed. The default setting is full du plex. The mode may be changed using “UP” or “DOWN” and pressing “SET”.

7.1.2.4 Linefeed

The final parameter in the serial interface menu is the linefeed mode. This pa rameter enables (“On”) or disables (“OFF”) transmission of a linefeed charac ter (LF, ASCII 10) after transmission of any carriage-return. The default setting is with linefeed on. The mode may be changed using “UP” or “DOWN” and pressing “SET”.

7.1.3 Serial Operation

Once the cable has been attached and the interface set up properly the control ler immediately begins transmitting temperature readings at the programmed rate. The serial communications uses 8 data bits, one stop bit, and no parity. The set-point and other commands may be sent via the serial interface to set the temperature set-point and view or program the various parameters. The inter

7 Digital Communication Interface

IEEE-488 Communication

face commands are discussed in Section 7.3. All commands are ASCII charac ter strings terminated with a carriage-return character (CR, ASCII 13).

7.2 IEEE-488 Communication

The IEEE-488 interface is available as an option. Instruments supplied with this option may be connected to a GPIB type communication bus that allows many instruments to be connected and controlled simultaneously. To eliminate noise, the GPIB cable should be shielded.

7.2.1 Setup

To use the IEEE-488 interface first connect an IEEE-488 standard cable to the back of the calibrator. Next set the device address. This parameter is pro grammed within the IEEE-488 interface menu.

To enter the IEEE-488 parameter programming menu first press “EXIT” while pressing “SET” and release to enter the secondary menu. Press “SET” repeat edly until the display reaches “PrObE”. This is the menu selection. Press “UP” repeatedly until the IEEE-488 interface menu is indicated with “IEEE”. Press “SET” to enter the IEEE-488 parameter menu. The IEEE-488 menu contains the IEEE-488 address parameter.

7.2.2 IEEE-488 Interface Address

The IEEE-488 address is prompted with “AddrESS”. Press “SET” to program the address. The default address is 22. Change the device address of the calibrator if necessary to match the address used by the communication equipment by pressing “UP” or “DOWN” and then “SET”.

IEEE-488 Operation Commands may now be sent via the IEEE-488 interface to read or set the temperature or access other controller functions. All com mands are ASCII character strings and are terminated with a carriage-return (CR, ASCII 13). Interface commands are listed below.

7.3 Interface Commands

The various commands for accessing the calibrator functions via the digital in terfaces are listed in this section (see Table 3). These commands are used with both the RS-232 serial interface and the IEEE-488 GPIB interface. In either case the commands are terminated with a carriage-return character. The inter face makes no distinction between upper and lower case letters therefore either may be used. Commands may be abbreviated to the minimum number of letters that determines a unique command. A command may be used to either set a pa rameter or display a parameter depending on whether or not a value is sent with the command following a “=” character. For example: “s” returns the current set-point and “s=150.00” sets the set-point to 150.00 degrees.

In the following list of commands, characters or data within brackets, “[” and “]”, are optional for the command. A slash, “/”, denotes alternate characters or

9116A Furnace

User’s Guide

data. Numeric data, denoted by “n”, may be entered in decimal or exponential notation. Characters are shown in lower case although upper case may be used. Spaces may be added within command strings and are ignored. Backspace (BS, ASCII 8) may be used to erase the previous character. A terminating CR is im plied with all commands.

Tabl e 3. Digital Interface Command Summary

7 Digital Communication Interface

Interface Commands

Command Description

Display Temperature

Read current set-point s[etpoint] s set: 9999.99 {C or F} set: 150.00 C

Set current set-point to n s[etpoint]=n s=450 Instrument

Read scan function sc[an] sc scan: {ON or OFF} scan: ON

Set scan function: sc[an]=on/of[f]

Turn scan function on sc[an]=on sc=on

Turn scan function off sc[an]=of[f] sc-of

Read scan rate sr[ate] sr srat: 999.99 {C or F}/min srat: 10.0 C/min

Setscanrateto minute

Read temperature t[emperature] t t: 9999.99 {C or F} t: 55.69 C

Secondary Menu

Read proportional band setting pr[op-band] pr pb: 999.9 pr: 15.9

Set proportional band to

Read cutout setting c[utout] c c: 9999 {C or F} c: 620 C, in

Set cutout setting: c[utout]=n/r[eset]

Set cutout to

Reset cutout now c[utout]=r[eset] c=r

Read heater power

(duty cycle)

Ramp and Soak Menu

Read number of programmable set-points

Set number of programmable set-points to

Read programmable set-point number

Set programmable set-point num

nton

ber

Read program set-point soak time

Set program set-point soak time to

minutes

Read program control mode pc pc prog: {OFF or ON} prog: OFF

degrees per

degrees c[utout]=n c=500 Temperature

Command Format

sr[ate]=

pr[op-band]=n pr=8.83 Depends on

po[wer] po p%: 9999 po: 1

pn pn pn: 9 pn: 2

pn=

psn=

pt pt ti: 999 ti: 5

pt=

Command Example Returned

sr=5 .1 to 100°C

pn=4 1 to 8

ps3 psn: 9999.99 {C or F} ps1: 50.00 C

ps3=50 1 to 8, Instru

pt=5 0 to 500

Returned Example

Acceptable Values

Range

ON or OFF

Configuration

Range

ment Range

9116A Furnace

User’s Guide

Digital Interface Command Summary continued

Command Description

Set program control mode: pc=g[o]/s[top]/c[ont]

Start program pc=g[o] pc=g

Stop program pc=s[top] pc=s

Continue program pc=c[ont] pc=c

Read program function pf pf pf: 9 pf: 3

Set program function to

Configuration Menu

Probe Menu

Read R0 calibration parameter r[0] r r0: 999.999 r0: 100.578

Set R0 calibration parameter to

Read ALPHA calibration parameter

Set ALPHA calibration parameter to

Read DELTA calibration parameter

Set DELTA calibration parameter to

Operating Parameters Menu

Set temperature units: u[nits]=c/f

Set temperature units to Celsius u[nits]=c u=c

Set temperature units to Fahrenheit

Read cutout mode cm[ode] cm cm: {xxxx} cm: AUTO

Set cutout mode: cm[ode]=r[eset]/a[uto]

Set cutout to be reset manually cm[ode]=r[eset] cm=r

Set cutout to be reset automatically

Read approach setting ap[proach] ap ap:9 ap:5

Set approach setting to degrees

Read stability ts ts ts:9.9 ts:0.5

Set soak stability to

Serial Interface Menu

Read serial sample setting sa[mple] sa sa: 9 sa: 1

degrees ts=

Command Format

pf=

r[0]=n r=100.324 98.0 to 104.9

al[pha] al al: 9.9999999 al: 0.0038573

al[pha]=n al=0.0038433 .00370 to

de[lta] de de: 9.99999 de: 1.46126

de[lta]=

u[nits]=f u=f

cm[ode]=a[uto] cm=a

ap[proach]=

Command Example Returned

pf=2 1to4

de=1.45 0.0 to 2.9

ap=15 0 to 20°C

ts=.1 .01 to 4.99°C

Returned Example

Acceptable Values

GO or STOP or CONT

.00399

CorF

RESET or AUTO

Digital Interface Command Summary continued

7 Digital Communication Interface

Interface Commands

Command Description

Set serial sampling setting to seconds

Set serial duplex mode: du[plex]=f[ull]/h[alf]

Set serial duplex mode to full du[plex]=f[ull] du=f

Set serial duplex mode to half du[plex]=h[alf] du=h

Set serial linefeed mode: lf[eed]=on/of[f]

Set serial linefeed mode to on lf[eed]=on lf=on

Set serial linefeed mode to off lf[eed]=of[f] lf=of

Calibration Menu (WARNING – changing the following calibration values may change the accuracy of the instrument.)

Read C0 calibration parameter *c0 *c0 c0: 9 c0: 0

Set C0 calibration parameter to

Read CG calibration parameter *cg *cg cg: 999.99 cg: 406.25

Set CG calibration parameter to

These commands are only used for factory testing.

Read software cutout mode *sco *sco sco: {ON or OFF} sco: ON

Set software cutout mode: *sco=ON/OF[F]

Set software cutout mode on *sco=ON *sco=on

Set software cutout mode off *sco=OF[F] *sco=off

Miscellaneous (not on menus)

Read firmware version number *ver[sion] *ver ver.9999,9.99 ver.9123,3.54

Read structure of all commands h[elp] h list of commands

Legend: [] Optional Command data

Note: When DUPLEX is set to FULL and a command is sent to READ, the command is returned followed by a

Command Format

sa[mple]=

*c0=n *c0=0 –999.9 to 999.9

*cg=n *cg=406.25 –999.9 to 999.9

/ Alternate characters or data

{} Returns either information

n Numeric data supplied by user–may be entered in decimal or exponential notation

9 Numeric data returned to user

x Character data returned to user

carriage return and linefeed. Then the value is returned as indicated in the RETURNED column.

Command Example Returned

sa=0 0 to 4000

Returned Example

Acceptable Values

FULL or HALF

ON or OFF

8 Fixed Point Cell Installation Instructions

Installing the Metal Freeze Point Cell

8 Fixed Point Cell Installation Instructions

CAUTION: An Inconel basket is used as the example for the installation

instructions in this section. The furnace is shipped with an Alumina basket which does not have a locking mechanism for the lid. DO NOT install the basket into the furnace with the lid installed, otherwise the cell and the basket may be broken. The Alumina basket needs to be installed before the basket lid is placed on the basket.

8.1 Installing the Metal Freeze Point Cell

CAUTION: Never touch the cell with bare hands. When handling the cell,

wear gloves.

CAUTION: The support canister must also be free of oils and other con-

taminating materials.

A metal freeze point cell must always be handled with extreme care due to its high value and fragility. It must also be kept free of any foreign material such as finger oils. Alkaline from these oils cause devitrification or physical breakdown of the quartz shell. Handle the cell with cotton gloves. Discard the gloves before they become appreciably soiled. Any foreign material should be carefully removed with high purity alcohol. Refer to Figure 9 on page 48.

Sealed cells for freezing points are delicate devices and the quartz shell is prone to be broken. THE CELL MUST BE HANDLED WITH EXTREME CARE.

Maintain the cell in vertical orientation for safety. Although putting the cell in horizontal orientation for a short period of time may not cause any damage, transporting the cell by any means while in this position is dangerous. Trans porting a cell by common carrier is also dangerous. The cell should be hand carried from one place to another. Keep the surface of the cell clean.

8.2 Purpose

To maintain uniform cell installation throughout the laboratory.

Equipment needed:

•

Cell basket and Lid

•

Reagent grade alcohol

•

Fixed Point Cell

•

Sheet of standard printer paper

•

Insulation

9116A Furnace

Alumina Cap

Alumina Support Canister or “Basket”

Fiber Ceramic Paper to center cell in canister

Metal Freeze Point Cell (cell interior construction shown)

Quartz Shell

Graphite Crucible

Quartz

Reentrant Tube

High Purity

Metal Sample

Fiber Ceramic Cushion, 25.4 mm (1 in)

Insulation

TopTher mal Shunt Disk

Insulation

Insulated Reflector Assy

Insulation

Fiber Ceramic

Board

Bottom Thermal Shunt Disk

User’s Guide

Figure 9. Metal Freeze Point Cell installed in canister

♦

Circular 2.54 cm (1 in) thick for below cell in basket

♦

Circular 0.64 cm (0.25 in) thick with hole in center for over the cell

♦

12.7 cm x 5.72 cm x 0.004 cm (5 in x 2.25 in x 0.016 in) fiber ceramic paper for cushioning around cell

♦

0.64 cm (0.25 in) diameter piece to be placed in the re-entrant well of the cell

Quartz rod

•

Cotton gloves

•

Paper towels

•

Stand to support cell

•

Cell installation/removal tool

•

8.3 Procedure

1. Remove cell from packaging and place in stand or support it in a vertical position.

8 Fixed Point Cell Installation Instructions

Procedure

Figure 10 Cell supported by stand.

9116A Furnace

User’s Guide

2. Put on cotton gloves to avoid contaminating cell with body oils.

Figure 11

Cotton gloves MUST be used.

8 Fixed Point Cell Installation Instructions

Procedure

3. Clean cell with reagent grade alcohol to remove any dust or oil that may be on the cell.

Figure 12 Preparing paper towel with reagent grade alcohol.

9116A Furnace

User’s Guide

Figure 13 Clean cell completely.

4. Return cell to stand(see Figure 10).

5. Place the 0.64 cm (0.025 in) diameter piece of insulation in the re-entrant well of the cell.

8 Fixed Point Cell Installation Instructions

Procedure

Figure 14 Place insulation in re-entrant well.

9116A Furnace

User’s Guide

6. Using quartz rod move insulation to the bottom of the cell.

Figure 15 Push insulation to bottom of re-entrant well.

8 Fixed Point Cell Installation Instructions

7. Clean cell basket with reagent grade alcohol

Procedure

Figure 16 Clean the basket thoroughly

9116A Furnace

User’s Guide

8. Place 2.54 cm (1 in) thick piece of insulation in the cell basket.

Figure 17 Place insulation in cell basket

8 Fixed Point Cell Installation Instructions

Procedure

9. Use quartz rod to verify that insulation is at the bottom of the basket and flat.

Figure 18 Insure the insulation is flat at the bottom of the cell basket.

9116A Furnace

User’s Guide

10. Make a 21.6 x 14 cm (8.5 x 5.5 in) piece of paper from standard printer paper. This paper is used to protect the cell from being scratched while installing the cell into the basket..

Figure 19 21.6 x 14 cm (8.5 x 5.5 in) paper

8 Fixed Point Cell Installation Instructions

11. Roll the paper lengthwise and place it in the opening of the basket.

Procedure

Figure 20 Paper placement.

9116A Furnace

User’s Guide

12. Hold basket horizontally and slide cell into basket. Push with your fin

ger until cell reaches bottom of the basket.

Figure 21 Insert cell into basket.

13. Remove paper and return cell and basket to stand in the vertical position.

8 Fixed Point Cell Installation Instructions

Procedure

14. Roll a 12.7 x 5.72 x 0.04 cm (5 x 2.25 x 0.016 in) piece of f iber ceramic paper width wise and place it in the cell basket.

Figure 22 Place fiber ceramic paper to center the cell in cell basket.

9116A Furnace

User’s Guide

15. Slide fiber ceramic paper into basket.

Figure 24 Fiber ceramic paper pushed below cell basket top.

16. Place a circular 0.64 cm (0.25 in) thick piece of insulation on top of the cell and use rod to verify the alignment of the hole in the insulation.

Figure 23 Fiber ceramic insulation installed on top of cell.

8 Fixed Point Cell Installation Instructions

Procedure

CAUTION: An Inconel basket is used as the example for the installation

17. Place the cell removal/installation tool into the holes on the basket. Us ing both hands, one on the removal/installation tool, lift and move basket assembly into the furnace.

Figure 25 Preparing basket assembly for installation in furnace.

9116A Furnace

User’s Guide

18. Slowly insert cell into furnace.

Figure 26 Installing basket assembly in furnace.

8 Fixed Point Cell Installation Instructions

Procedure

19. Place the cell removal/installation tool into the holes on the lid. Carefully install the lid onto the basket, where the basket was installed previously in the furnace.

20. Place one circular 2.54 cm (1 in) thick piece of insulation on top of bas ket.

Figure 27 Width of insulation placed on top of basket assembly.

21. Place the top thermal shunt disk in the furnace.

22. Place one circular 2.54 cm (1 in) thick piece of insulation on top of the thermal shunt disk.

9116A Furnace

User’s Guide

23. Install the furnace lid (Figure 28).

Figure 28 Basket, insulation, and furnace lid installed .

8 Fixed Point Cell Installation Instructions

24. Install the heat radiation guard (Figure 29).

Procedure

Figure 29 Heat radiation guard installed.

9 Freeze Point Realization

9.1 General

This discussion assumes SPRT calibrations at the copper point. Other freeze points are similar.

Successful copper point realization requires a cell of the following specifications:

The purity of copper: 99.9999%

•

The reproducibility: 5 mK

•

The expanded uncertainty: 30 mK

•

The outer diameter of the cell: 48 mm

•

†

The expanded uncertainty was evaluated at the level of two standard deviations

(95% confidence)

9.2 How to Realize the Freezing Point of Copper

1) Melting the Cell: Switch on the power to the furnace from the front panel. The ramp rate of the furnace should not be set too high. Set the ramp rate of the instrument should be set such that the furnace heats from ambient (approximately 25°C) to 550°C in no less than 2.5 hours and an additional 1-1.5 hours to reach 1084°C. The final step from 1084°C to 1090°C should take approximately 20 minutes. The ramp rates are programmable from the controller. Use a working high temperature platinum resistance thermometer or a Type S (Type R) thermocouple to monitor the temperature in the cell. When the copper sample begins to melt, the temperature stops rising and remains almost constant during the melting process. Write down the resistance or EMF indicated by the working thermometer at the melting point for future reference.

2) As soon as the copper sample is melted completely, set the furnace at a temperature of about 3°C higher than the freezing point. Maintain a sta ble temperature for 20 minutes. Then let the temperature of the furnace decrease at a rate of 0.2 to 0.3°C per minute until the temperature indi cated by the working thermometer stops decreasing and starts to rise. This indicates that freezing has started. Usually the copper may super cool by an amount approximately 1°C or more before the start of freez ing. Take the working thermometer out of the furnace and put the ther mometer or thermocouple to be calibrated into the furnace. Meanwhile, maintain the temperature of the furnace at a temperature between 0.5 and

1.0°C lower than the freezing point.

†

General

9116A Furnace

User’s Guide

3) Initiating the Freeze and Making Measurements: The freezing curve usu ally lasts more than 4 hours and the temperature in the first half of the freezing curve is usually stable within 0.2 mK or 0.3 mK. If the tempera ture of the furnace is closer to the freezing point, a longer freezing point can be obtained. A freezing curve longer than 10 hours or more is not difficult to obtain if the temperature of the furnace is carefully controlled.

The first thermometer to be calibrated should not be preheated. The cold thermometer enhances the rate of freezing at the beginning of freezing, i.e. “induces” the freezing.

Take the average of several thermometer resistance or thermocouple volt age readings over a period of about 10 minutes. This average is the resis tance or voltage at the freezing point of copper R

Several probes can

Cu.

be calibrated during one freezing curve.

Since a cold thermometer absorbs a large amount of heat which shortens the freezing curve greatly, subsequent thermometers to be calibrated should be preheated to a temperature very near the freezing point before inserting each into the copper cell. Another advantage of preheating is that the equilibrium time in the cell may be shortened by nearly one-half, i.e. from about 20 minutes to 10 minutes.

Preheat the thermometers for 20 minutes or so near the freezing point. Preheating the thermometers for too long is unnecessary and should not be done. The thermometer sensors could possibly be contaminated if they remain in metal wells for a long period of time.

4) SPRT Annealing: The rapid cooling from the freezing point of copper to room temperature introduces extra crystal defects - vacancies in the platinum wire of the thermometer - resulting in a noticeable increase in resis tance at the triple point of water (R

). Sometimes a change larger than

the equivalent of 30 mK can be observed. An appropriate annealing gets rid of these defects and returns the R

to the equilibrium value. Anneal

the thermometer at 700°C for 2 hours in a clean furnace and then cool it from 700°C to 450°C over 3 hours. An alternative annealing procedure is to anneal at 970°C for 30 minutes and then cool at a constant rate to 500°C over a period of 4 hours. After annealing the thermometer, take it out of the furnace and cool it to room temperature in air. Measure the R and calculate the resistance ratio WCu:

A thermocouple does not need to be annealed after calibration at the freezing point of copper.

10 Calibration Procedure

CAUTION: The vertical gradient needs to be checked before calibrating

the furnace. Checking the vertical gradient insures that the sodium heat-pipe is working properly.

CAUTION: DO NOT change the value of the calibration parameter

Delta. Delta is set to at the factory (to the value of 1.6) for optimum per formance of the furnace.

The user may want to calibrate the furnace to improve the temperature set-point accuracy. Calibration is done by adjusting the controller probe calibration con stants R0 and ALPHA so that the temperature of the furnace as measured with a standard thermometer agrees more closely with the set-point. The thermome ter used must be able to measure the well temperature with higher accuracy than the desired accuracy of the furnace.

10.1 Two Point Calibration Procedure

In some instances the user may want to calibrate the controller to improve the temperature set-point accuracy. Calibration is done by adjusting the controller probe calibration constants R measured with a standard thermometer, agrees more closely with the set-point. The thermometer used must be able to measure the temperature with higher accuracy than the desired accuracy of the system.

1. The two set-points that should be used for the calibration are 800°C and 1060°C, since they are used at the factory to calibrate the furnace.

2. Set the controller to the low set-point. When the calibrator reaches the set-point and is stable (< 0.1°C change in 15 minutes), take a reading from the reference thermometer. Sample the set-point resistance by holding down the SET key and pressing the DOWN key. Write these values down as T respectively.

3. Repeat step 2 for the second set-point recording it as T

4. Using the recorded data, calculate new values for R using the equations given below:

and ALPHA so that the process temperature, as

10 Calibration Procedure

Two Point Calibration Procedure

and R

and R2.

and ALPHA parameters

10.1.1 Compute R0& ALPHA:

⎡

⎤

⎡

⎢

⎥

1001100

⎣

⎦

⎡

⎤

⎢

⎥

1001100

⎣

⎦

⎤

−

⎢

⎥

⎣

⎦

⎡

⎤

−

⎢

⎥

⎣

⎦

9116A Furnace

User’s Guide

10.1.2 Accuracy & Repeatability

Ra Ra

−

21 12

−

Ra Ra

−

21 12

- Measured temperature using thermometer.

- Value of R from display of furnace (Press SET and DOWN at the same

rzero

alpha

1-2

time.)

where

and R1are the measured temperature and resistance at 800.0 °C

and R2are the measured temperature and resistance at 1060.0 °C

5. Program the new values for R

(rzero) and ALPHA (alpha) into the

instrument.

1. Check the accuracy of the calibrator at various points over the calibrated

range.

2. If calibrator does not pass specification at all set-points, repeat the Calibra-

tion Procedure.

11 Maintenance

The calibration instrument has been designed with the utmost care. Ease of op eration and simplicity of maintenance have been a central theme in the product development. Therefore, with proper care the instrument should require very little maintenance. Avoid operating the instrument in an oily, wet, dirty, or dusty environment.

If the outside of the instrument becomes soiled, it may be wiped clean

•

with a damp cloth and mild detergent. Do not use harsh chemicals on the surface which may damage the paint.

Be sure that the well of the furnace is kept clean and clear of any foreign

•

matter. DO NOT use fluids to clean out the well.

If a hazardous material is split on or inside the equipment, the user is re

•

sponsible for taking the appropriate decontamination steps as outlined by the national safety council with respect to the material.

If the mains supply cord becomes damaged, replace it with a cord of the

•

appropriate gauge wire for the current of the instrument. If there are any questions, call Hart Scientific Customer Service for more information.

• Before using any cleaning or decontamination method except those rec-

ommended by Hart, users should check with Hart Scientific Customer Service to be sure that the proposed method will not damage the equipment.

• If the instrument is used in a manner not in accordance with the equip -

ment design, the operation of the furnace may be impaired or safety hazards may arise.

• The over-temperature cut-out should be checked every 6 months to see

that it is working properly. In order to check the user selected cut-out, fol low the controller directions (Section 6) for setting the cut-out.

•

Adjustment of Temperature Uniformity: Vertical uniformity should be measured in a freeze point cell just below the melting point of the cell. The vertical temperature uniformity in the cell should be within the limit specified in Section 2.1, Specifications, for a distance of 10.2 cm (4 in) upwards from the bottom of the central well (See Figure 30 on page 74). A periodic check of the temperature uniformity using a Type R or Type S thermocouple is recommended at least once every year. If the vertical gra dient is not within the limit specified in Section 2.1, Specifications, the heat pipe may not be functioning properly. Contact an Authorized Service Center.

A properly operating heat pipe will keep the area around the cell or test area uniform in temperature. However, the open end of the pipe can allow some heat loss that can cause a gradient inside. Thermal shunts and insu lation are intended to inhibit this loss. On the other hand, the heat pipe re quires some heat loss at its top to promote condensation of the sodium vapor. The balance may be adjusted by adjusting the amount of insulation between the plates of the reflectors of the assembly that covers the access

Thermocouple

Melted Cell

10.2 cm

(4 in)

Insulation

Adjust amount of insulation to adjust uniformity

1.2 cm (0.5 in) Fiber Ceramic board

Figure 30. Testing Uniformity

opening. The fiber ceramic insulation provided may be added or removed to do this. Generally the bottom position must be filled and additional spaces above may be filled as required.

Check of the Controller Set-point Accuracy: This test is carried out in

•

a metal freeze point cell where the metal has been completely melted. Prepare the furnace in the same fashion as though a freeze plateau would be conducted up to the point that the metal sample is melted. This exam ple illustrates measurements made near the silver point:

♦

Set the temperature of the furnace at 964°C and allow it to stabilize as would be done in preparation for a freeze. Measure the EMF of a ther mocouple inserted into the cell. Compare the measured EMF to one taken at the M.P. or F.P. The actual temperature, t, in the cell can be calculated by using the following equation:

−

=°+

961 78

..C

0 0114

mV C

where E1is the measurement EMF and E0is the EMF at the M.P. (961.78°C is the M.P. temperature of copper for this example) and 0.0114mV/°C is the sensitivity of a Type S thermocouple near the M.P. of silver.

For example, the measured EMF E E

=9.1481 mV, the actual temperature in the furnace.

−

91502 91481

t =+

0 0114

=9.1502 mV, the EMF at the M.P.

=°961 78

961 96.

. C

Since t=964.0°C = the actual set-point, the error, if any, is very small. If the error is larger than 1°C, you can make an adjustment to the set-point.

12 Troubleshooting

Troubleshooting

If problems arise while operating the 9116A, this section provides some sug gestions that may help you solve the problem.

12.1 Troubleshooting

Below are several situations that may arise followed by suggested actions to take for fixing the problem.

Problem

The heater indicator LED stays red but the tempera ture does not increase

The controller display flashes “Cut-out” and the

heater does not operate

Causes and Solutions

The display does not show “cutout” nor displays an incorrect instrument

temperature, but the controller otherwise appears to operate normally. The problem may be either insufficient heating or no heating at all. One or more burned out heaters or blown heater fuses may also cause

this problem. If the heaters seem to be burned out, contact an Authorized Service Center (see Section 1.4) for assistance.

The display flashes “Cut-out” alternately with the process temperature. If the process temperature displayed seems grossly in error, consult the

following problem: ‘The display flashes “Cut-out ” and an incorrect process temperature’.

Normally, the cutout disconnects power to the heater when the instrument temperature exceeds the cutout set-point causing the temperature to drop back down to a safe value. If the cutout mode is set to “AUTO”, the heater switches back on when the temperature drops. If the mode is set to “RESET”, the heater only comes on again when the temperature is reduced and the cutout is manually reset by the operator, see Section 6.9 Cutout. Check that the cutout set-point is adjusted to 10 or 20°C above the maximum instrument operating temperature and that the cutout mode is set as desired.

If the cutout activates when the instrument temperature is well below the cutout set-point or the cutout does not reset when the instrument temper ature drops and it is manually reset, then the cutout circuitry or the cutout thermocouple sensor may be faulty or disconnected. Contact an Autho

rized Service Center (see Section 1.4) for assistance.

9116A Furnace

User’s Guide

Problem

The display flashes “Cut-out” and an incorrect process temperature

The displayed process temperature is in error and the controller remains in the cooling or heating state at any set-point value

Causes and Solutions

The problem may be that the controller’s voltmeter circuit is not function ing properly.

A problem with the thermocouple probe, the cutout operation, or the cut out circuitry may cause the cutout to remain in this condition.

Check that the thermocouple probe is plugged into the controller and wired correctly. Check that the probe temperature is well below the pro grammed set-point. If not then reset the cutout temperature to a value well above the probe temperature or wait for the temperature to cool well below the cutout set-point. If the cutout is set for manual reset mode then after the temperature cools the user must also manually reset the cutout according to the directions in this manual under Section 6.9, Cutout. If the probe is not connected to the controller, plug in the appropriate thermo couple probe into the cutout probe socket.

A nearby large static discharge may also affect data in memory. Verify that the parameters on the Report of Test are accurate. Cycle the power off, disconnect the instrument from AC, and then restart the instrument.

The controller may need to be reset using the Factory Reset Sequence listed below, but should only be performed if a current Report of Test is available, since performing the Factory Reset Sequence sets all controller parameters to default.

Factory Reset Sequence. Hold the SET and EXIT buttons down at the same time while powering up the instrument. The instrument display shows ‘-init-’, the model number, and the firmware version. Each of the controller parameters and calibration constants must be reprogrammed. The values can be found on the Report of Test that was shipped with the instrument.

Possible causes may be either a faulty control probe or erroneous data in memory. The probe may be disconnected, shorted, or burned out. Check that the probe is connected properly. If wired properly, the probe

may be checked with an ohmmeter to see if it is open or shorted. The probe is a platinum 4-wire Din 43760 type. The resistance should read 0.2 to 2.0 ohms between pins 1 and 2 on the probe connector and 0.2 to 2.0 ohms between pins 3 and 4. It should read 10 [at 0°C (32°F)] to 50 ohms [at 1100°C (32°F)] between pins 1 and 4 depending on the temperature of the instrument. If the probe appears to be defective, contact an Autho rized Service Center (see Section 1.4) for assistance.

If the problem is not the probe, erroneous data in memory may be the cause. Re-initialize the memory as discussed in the problem ‘The display flashes “Cut-out” and an incorrect process temperature’. If the problem re

mains, the cause may be a defective electronic component.

12 Troubleshooting

Troubleshooting

Problem

The controller controls or attempts to control at an inaccurate temperature

The controller shows that the output power is steady, but the process tempera ture is unstable

The controller alternately heats for a while then cools

The controller erratically heats then cools, control is unstable

The controller does not maintain

controller pa rameters or parame ters are reset each time the power to the unit is removed

Causes and Solutions

The controller operates normally except when controlling at a specified set-point. At this set-point, the temperature displayed does not agree with the temperature measured by the user’s reference thermometer to within the specified accuracy. This problem may be caused by an actual differ ence in temperature between the points where the control probe and ther mometer probe measure temperature, by erroneous instrument calibration

parameters, or by a damaged control probe. Check that the thermometer probe and control probe are both fully in

serted into the instrument to minimize temperature gradient errors. Check that the calibration parameters are all correct according to the Re

port of Test. If not, re-program the constants. Check that the control probe has not been struck, bent, or damaged. The instrument may be out of calibration, therefore it may be necessary to

perform the calibration procedure explained in the calibration section of this manual.

Possible cause is an improper proportional band setting. If the instrument temperature does not achieve the expected degree of

stability when measured using a thermometer, try adjusting the propor tional band to a narrower width as discussed in Section 6.8, Proportional

Band.

The instrument is not stable and the duty cycle is not constant. The proportional band being too narrow typically causes this oscillation.

Increase the width of the proportional band until the temperature stabilizes as discussed in Section 6.8, Proportional Band.

If both the instrument temperature and output power do not vary periodically but in a very erratic manner, the problem may be excess noise in the system. Noise due to the control sensor should be very small. However, if the probe has been damaged or has developed an intermittent short or

open, erratic behavior may exist. Check for a damaged probe or poor connection between the probe and

controller. Intermittent shorts in the heater or controller electronic circuitry may also

be a possible cause. Contact an Authorized Service Center (see Section

1.4, on page 5) for assistance.

Note: Before performing the memory check, you need to record the con troller calibration parameters (found in the CAL menu of the instrument) and any user-adjusted parameters that you have changed (such as the programmable set points and proportional band).

Memory Check

Doing a memory check is the easiest way to verify the ability of the bat tery to maintain controller parameters.

1. Power off the instrument.

2. Disconnect the instrument from AC power for 10 seconds.

3. Reconnect the AC power and power on the instrument.

4. If the display shows InIT and/or the cycle count shows a low number such as 0002, the battery is spent and should be replaced. Contact an Authorized Service Center for assistance.

5. After replacing the battery, you must reprogram the calibration and user-adjustable parameters into the controller.

Fluke 9116A 9116A Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Table of Contents

Figures and Tables