Kistler 8774B100SSP Owner's manual

Brand: Kistler

Model: 8774B100SSP

Type: Owner's manual

Instruction

Manual

Ceramic shear

accelerometers

(Low impedance,

Voltage mode)

Types

8714B...,

8740A...,

8774B...,

8775A...,

8776B...,

8778A...,

8784A...,

8786A...

8714B_002-777e-10.23

Foreword

8714B_002-777e-10.23

Thank you for choosing a Kistler quality product characterized

by technical innovation, precision and long life.

Information in this document is subject to change without notice.

Kistler reserves the right to change or improve its products and

make changes in the content without obligation to notify any

person or organization of such changes or improvements.

tected by various intellectual property rights. For more details

visit www.kistler.com. The Kistler Group includes Kistler Holding

AG and all its subsidiaries in Europe, Asia, the Americas and

Australia.

Kistler Group

Eulachstrasse 22

8408 Winterthur

Switzerland

Tel. +41 52 224 11 11

info@kistler.com

www.kistler.com

Page 1

8714B_002-777e-10.23Page 2

Ceramic shear accelerometers

Content

1. Introduction .......................................................................................................................................4

2. Important information ......................................................................................................................5

2.1 Using this manual ...................................................................................................................5

2.2 For your safety .......................................................................................................................5

2.3 Precautions ............................................................................................................................6

2.4 Disposal of electronic equipment ...........................................................................................6

2.5 Nomenclature .........................................................................................................................7

3. Product description ..........................................................................................................................8

3.1 Supplied items ........................................................................................................................8

4. Technical information, functional description ...............................................................................9

4.1 Piezoelectric measurement concept ......................................................................................9

4.2 Ceramic shear background ....................................................................................................9

4.3 Low impedance (IEPE) output..............................................................................................10

4.4 Accessories ..........................................................................................................................12

4.4.1 Studs .......................................................................................................................12

4.4.2 Mounting block ........................................................................................................12

4.4.3 Cables .....................................................................................................................13

5. Installation.......................................................................................................................................14

5.1 General.................................................................................................................................14

5.2 Surface preparation ..............................................................................................................15

5.3 Stud mounting ......................................................................................................................15

5.4 Direct adhesive mounting .....................................................................................................16

5.5 Adapter for adhesive mounting.............................................................................................18

5.6 Mounting with wax ................................................................................................................18

5.7 Magnetic mounting ...............................................................................................................19

5.8 Summary of mounting methods ...........................................................................................20

5.9 Securing cables ....................................................................................................................21

5.10 Mass loading eects ...........................................................................................................22

6. Operating instructions ...................................................................................................................23

6.1 Powering ..............................................................................................................................23

6.1.1 Using "Built-In" power sources................................................................................23

6.1.2 Kistler couplers .......................................................................................................24

6.1.3 The constant current power supply/coupler ............................................................24

6.1.4 Sensor power-up ....................................................................................................26

Page 38714B_002-777e-10.23

Content

Total pages: 50

6.1.5 Overload recovery ..................................................................................................27

6.1.6 Supply voltage eects .............................................................................................27

6.1.7 Driving long cables .................................................................................................28

6.1.8 Ground loops ..........................................................................................................30

6.1.9 Ground isolation ......................................................................................................32

6.1.10 Frequency Response limits ..................................................................................32

6.1.11 Frequency Response denition and standards .....................................................32

6.1.12 High Frequency limitations ...................................................................................33

6.1.13 Low Frequency limitations - accelerometer ..........................................................34

6.1.14 Low Frequency limitations - coupler and read-out instrumentation ......................35

7. Technical data .................................................................................................................................36

8. Calibration and maintenance ........................................................................................................37

8.1 Calibration ............................................................................................................................37

8.2 Maintenance .........................................................................................................................37

8.3 Troubleshooting ....................................................................................................................38

8.4 Repairs .................................................................................................................................38

8.4.1 Type 8778A500M14 power & signal replacement leads .........................................39

8.5 Cleaning ...............................................................................................................................40

8.6 Calibration ............................................................................................................................41

9. Storage and transit considerations ..............................................................................................42

10. Warranty ........................................................................................................................................43

11. Declaration of conformity ............................................................................................................44

8714B_002-777e-10.23

Ceramic shear accelerometers

Page 4

Thank you for choosing a quality product from Kistler. Please

read through this manual thoroughly to enable you to fully

utilize the various features of your product.

To the extent permitted by law Kistler accepts no liability if

this instruction manual is not followed, or if products other

than those listed under Accessories are used.

These instructions describe Kistler Ceramic Shear Accelero-

meters.

Performance features at a glance:

Small envelop

Lightweight

Low impedance voltage mode

High sensitivity, high resolution

Low transverse sensitivity

Conforming to ä

Kistler oers a wide range of products for use in measuring

technology:

Piezoelectric sensors for measuring force, torque, strain,

pressure, acceleration, shock, vibration and acoustic

emission

Strain gage sensor systems for measuring force and

torque

Piezoresistive pressure sensors and transmitters

Signal conditioners, indicators and calibrators

Electronic control and monitoring systems, as well as

software for specic measurement applications

Data transmission modules (telemetry)

Kistler also develops and produces measuring solutions

for the application elds engines, vehicles, manufacturing,

plastics and biomechanics sectors.

Our product and application brochures, in addition to our

detailed data sheets, will provide you with an overview of our

product range. All unit measurements provided are listed in

order of metric units, followed by imperial units [in brackets].

If you require additional help beyond what can be located

online or in this manual, please contact Kistler‘s extensive

support organization or visit us online at www.kistler.com.

1. Introduction

8714B_002-777e-10.23

Important information

Page 5

2. Important information

This product has been manufactured in compliance with

current valid safety regulations. It has left the factory in a

perfect, safe condition. In order to maintain this condition and

ensure safe operation, compliance is required with the inst-

ructions and warning notes contained within this manual or

imprinted on the product itself.

Compliance with local safety regulations, which may apply

to the use of power line operated electrical and electronic

equipment, is strongly recommended.

Do not drop the instrument.

Store in the case provided and in a clean, dry environ-

ment.

Power the instrument in accordance with the instructions

provided in this manual.

Do not mount accelerometers on high voltage surfaces.

Keep cable clear of power lines and open machinery.

It is essential for you to review the following information,

which is intended to ensure your personal safety when

working with the Ceramic Shear IEPE Accelerometers and

contribute toward a longer service life.

2.2 For your safety

2.1 Using this manual

Information contained herein includes a technical description,

installation and operating instructions, powering and

considerations for cable length for all Ceramic Shear

Accelerometers listed on the title page. Section 8 contains a

listing of mounting accessories and cables available to assist

with your measurement needs.

It is recommended that the entire manual be read prior to

installation and operation of Ceramic Shear Accelerometers.

The user who has prior experience with IEPE/Voltage mode

type accelerometers may want to conne reading to particular

sections of interest.

Information contained herein may be subject to change.

If there is any questions concerning the operation of this

product, contact your Kistler representative for assistance.

8714B_002-777e-10.23

Ceramic shear accelerometers

Page 6

2.4 Disposal of electronic equipment

2.3 Precautions

Compliance with the following precautionary measures is

vital to ensure safe and reliable operation:

▪ Never expose the instrument to contamination or oil mist.

▪ Never operate or store the instrument outside the specified

temperature range.

▪ Never exceed the maximum stated voltage.

▪ DO NOT OVER TIGHTEN while stud or screw mounting

the sensor

▪ Do not expose the unit to excessive shock, i.e. by using a

hammer or dropping the unit.

▪ When not in use, store the accelerometer in the container

supplied.

▪ The environment should be as dry, clean and free from

vibrations as possible.

▪ Keep the connector clean and covered when not in use.

▪ Follow the recommendations detailed in Section 8.2.

If there is evidence that safe operation is no longer possib-

le, the instrument must be powered o and rendered safe

against accidental start-up. Safe operation is no longer pos-

sible when the product:

▪ shows visible signs of damage

▪ is no longer operating

▪ has been subjected to prolonged storage under unsuitable

conditions

Do not discard old electronic equipment in municipal trash.

For disposal at end of life, please return this product to the

nearest authorized electronic waste disposal service or

contact your Kistler sales oce for disposal instructions.

8714B_002-777e-10.23

Important information

Page 7

Throughout this manual, special designations and

nomenclature are used for terms and concepts relating to

Ceramic Shear sensors. These are identied in Table 1.

Term Definition

Fs Full-scale

Es DC supply voltage (a/k/a compliance voltage)

Eb Bias voltage (from calibration certicate)

fFrequency in Hz

R1Output resistance of the coupler

R2Input resistance of the coupler

ICurrent in Amperes

CDecoupling Capacitor (Capacitance in Farads)

τTime Constant

EOutput in Volts, Peak

RRead-out impedance

ZInput impedance

IEPE Integrated Electronics Piezoelectric

Rs Source Resistor

TEDS Transducer Electronic Data Sheet

Table 1: Manual nomenclature

2.5 Nomenclature

Types 8714B…T, 8740A...T, and 8775A050T/TSP are

a 'smart sensor' version where an electronic data sheet

, showing basic accelerometer information, may be

viewed. This data sheet referred to by the acronym TEDS

(Transducer Electronic Data Sheet) requires additional

system components. Contact Kistler for details.

8714B_002-777e-10.23

Ceramic shear accelerometers

Page 8

3. Product description

3.1 Supplied items

Kistler ceramic shear IEPE accelerometers are shear

mode vibration measuring instruments. A self-generating

piezoelectric sensing element is used in conjunction with

the built-in internal circuit Piezotron® charge converter.

As with most accelerometers, the sensitivity of this

series is expressed in terms of the ratio of the electrical

output to applied acceleration (e.g. mV/g). In the case of

Piezotron devices such as ceramic shear, the output is a

low impedance voltage signal, which is proportional to the

applied acceleration. Being a low impedance device, no

external charge amplier or special cabling is required and

transmission over long lines is possible with a minimum of

noise pick-up.

All accelerometers designed for stud mounting are supplied

with appropriate studs. Units intended for adhesive mounting

are provided with Petro Wax. The supplied accessories are

included in the unit specications on the data sheet.

8714B_002-777e-10.23

Product description

Page 9

4. Technical information, functional description

This section provides the user with a quick means of

placing the Kistler Ceramic Shear Accelerometers into

operation. Careful installation will result in optimal, high

frequency response, accuracy and reliability. Dimensional

characteristics can be found on their respective data sheets.

4.1 Piezoelectric measurement concept

Piezoelectric accelerometers convert acceleration into an

electric charge. The charge derived by the accelerometer

is proportional to the force, from a known mass, acting on

the internal ceramic (piezoelectric) element. Accordingly, the

mechanical variable (acceleration) is derived from a force

measurement.

4.2 Ceramic shear background

A typical Kistler sensing assembly (See Fig. 1) consists of

a center post, piezoelectric ceramic element and a seismic

mass mechanically preloaded, with or without a preload bolt.

Since the unit is operated in a shear arrangement it will sense

motion perpendicular to the base. When the accelerometer

is attached to a vibrating structure, the mass exerts a shear

force on the ceramic element. This applied force causes the

piezoelectric material to produce an electric charge. Since

force is mass times acceleration (from Newton's second law),

the charge produced is proportional to acceleration, since m

is constant. This is represented by:

a = F

—

Fig. 1: Inside view of a typical single-axis, annular shear

accelerometer

8714B_002-777e-10.23

Ceramic shear accelerometers

Page 10

The Ceramic Shear sensing element oers many advantages

over previous compression mode designs. Due to its shear

construction, the accelerometer element is less sensitive to

thermal transients, transverse (cross-axis) motion, and the

eects of base strain than a compression element.

Kistler initially introduced the Shear design concept using a

quartz element that has become a standard with many users.

Ceramic Shear Accelerometers employ similar ring shear and

annular shear designs that provide the same advantages.

4.3 Low impedance (IEPE) output

Contained within the accelerometer housing is a miniature

electronic circuit. This circuit converts the high impedance

charge signal generated by the piezoelectric element into

a low impedance voltage output signal. All accelerometer

Types 8714B, 8740A, 8774B, 8775A, 8776B, 8778A, 8784A

and 8786A have a nominal output less than 500 ohms. The

integral charge amplier is powered by an external power

source (coupler) that uses a two-wire cable between the

accelerometer and coupler. The signal and power source

share a common line. The coupler provides a constant

current source to the accelerometer and decouples the DC

bias (see Section 6.1.3) from the measuring instrument. The

useable signal is seen as a varying voltage over an 11 VDC

(nominal) bias.

Low impedance accelerometers are ideally suited for appli-

cations where long cables are required, in high humidity or

other harsh environments. In addition, they eliminate the dif-

culties associated with high impedance outputs by providing

a voltage signal with low impedance and high frequency re-

sponse. The sensitivity of these accelerometers are given in

mV/g.

Table 2 depicts a typical low impedance measurement chain.

Couplers vary considerably in appearance, depending upon

the application and the number of sensors making up the

system. It can also be directly integrated to the data acquisi-

tion system.

8714B_002-777e-10.23

Product description

Page 11

Table 2: Low impedance measuring chain

Measuring Connecting Amplifying/Acquiring

Kistler LabAmp Type 5165A...

Signal Conditioning & Data

Acquisition (Analog & Digital Output)

IEPE Compatible Data Acquistion

Unit (customer supplied)

Type 1761B...

+ Type 1721

Type 87xx...

Sensor with

integral cable

Sensor without

integral cable

Type 87xx...sp

5050B

8202A

8702B

5165A

Data Accquisition Unit

8763B

8395A

8315A

5146A15

5134B

5165A

8714B_002-777e-10.23

Ceramic shear accelerometers

Page 12

4.4 Accessories

All accelerometers designed for stud mounting are supplied

with the appropriate studs. See Table 3 for more details re-

garding mounting stud dimensions, or refer to the unit speci-

fications listed on the respective data sheet for each model.

Type A B C D E Used with

8402 2.54

[0.10]

2.54

[0.10]

5.6

[0.22] 10-32 10-32 8784A...,

8786A...

8410 6.35

[0.25]

3.30

[0.13]

2.03

[0.08] ¼–28 10-32 8784A...,

8786A...

8411 2.79

[0.11]

6.60

[0.26]

10.4

[0.41] 10-32 M6 8784A...,

8786A...

8416 2.29

[0.09]

3.18

[0.13]

6.60

[0.26] 5-40 10-32 8740A...

4.4.1 Studs

Table 3: Mounting studs (dimensions in mm [in])

4.4.2 Mounting block

Type 8775A... can come with a unique mounting block, Type

8475AK01, to allow the sensor to be oriented in multiple di-

rections. See Figure 2 for more details regarding mounting

block dimensions.

Fig. 2: Type 8475AK01 (dimensions in in.)

8714B_002-777e-10.23

Product description

Page 13

4.4.3 Cables

Type 1511x · Output cable BNC pos. to BNC pos.

Type 1761B

· 10-32 pos. to BNC pos.

· Fluoropolymer jacketed

· Single-axis voltage mode/IEPE sensors

Type 1762B

· 10-32 pos. to 10-32 pos.

· Fluoropolymer jacketed extension cable

· Single-axis voltage mode/IEPE sensors

Type 1768A...K01

· 10-32 pos. to BNC pos.

· Flexible PVC jacketed extension cable

· Single-axis voltage mode/IEPE sensors

Type 1768A...K02

· 10-32 pos. to 10-32 pos.

· Flexible PVC jacketed extension cable

· Single-axis voltage mode/IEPE sensors

* Please refer to data sheet 000-471 for more details. Contact Kistler for any of your

cable needs.

Table 4: Most commonly used cables from Kistler (x = cable

length to be specied in meters)

8714B_002-777e-10.23

Ceramic shear accelerometers

Page 14

5. Installation

5.1 General

For proper operation of Ceramic Shear Accelerometers,

care must be taken during the installation process. Careful

installation will result in optimal high frequency response,

accuracy and reliability. Dimensional characteristics appear

on their respective data sheets.

Type 8714B...

Center hole

accelerometer

Type 8774B...A

Wax or adhesive

mounting

Type 8774B...S

Integral stud

mounting

Type 8776B...A

Wax or adhesive

mounting

Type 8776B...S

Integral stud

mounting

Type 8778A500

Wax or adhesive

mounting

Type 8778A500M14

Adhesive mount, ultra

mini, w/ replaceable

wire pair

Type 8784A5

Stud mounting

Type 8786A5

Stud mounting

Type 8775A...

Block or adhesive

mounting

Type 8740A...

Adhesive or stud

mounting

8714B_002-777e-10.23

Installation

Page 15

5.2 Surface preparation

A clean, at surface is necessary for both stud and adhesive-

mounted accelerometers. If the surface is not completely

at, the coupling between the accelerometer and the test

article introduces distortion into the measurement. A rough

surface creates voids between the mounting surfaces that

reduce high frequency transmissibility. For optimal frequency

response with stud and screw mount units, the surface

and hole preparation should be performed according to the

instructions in Table .... The roughness should not exceed 0.8

micrometers [32 micro inches].

5.3 Stud mounting

Types 8740A..., 8774B...S, 8776B...S, 8784A5, and 8786A5

accelerometers are specically designed for stud mounting.

The 8714B... is furnished with an insulated Type 8430K0(X)

mounting screws. Accelerometer Types 8774B...S and

8776B...S are furnished with a permanent, non-removable

stud. Types 8740A..., 8784A5 and 8786A5 have threaded

mounting holes machined in the base to accept a stud.

Kistler oers optional studs for convenient mounting in holes

other than threaded for 10-32. Most Kistler mounting studs

are machined from beryllium copper for high strength and

low modulus of elasticity, coupled with high elastic limits.

The studs are removable, allowing both stud and adhesive

mounting. The following guidelines must be followed when

stud mounting accelerometers:

1. Drill and tap an adequate hole to ensure a ush mount of

the accelerometer. Make sure the stud does not bottom

out, either in the mounting hole of the test structure or in

the accelerometer base. A chamfer should be machined

at the top of the mounting hole to ensure that the base of

the accelerometer makes full contact with the mounting

surface (see Table 5).

2. Completely clean the surface prior to mounting.

3. Apply a thin coat of silicon grease to both the acclerometer

and the mounting surface.

4. Always use the proper sockets and a torque wrench when

installing accelerometers. Tighten the accelerometer to

a torque of 2 ±0.2 N·m [18 ±2 in-lbs]. Note: For Types

8714B... and 8740A..., tighten the accelerometer to a

torque of 0.7 N·m [6 lbf-in]. DO NOT OVER TIGHTEN.

8714B_002-777e-10.23

Ceramic shear accelerometers

Page 16

Stud type D L1

mm [in]

8402 10-32 UNF 4.0 [0.16] 8.0 [0.31]

8410 10-32 UNF 4.0 [0.16] 8.0 [0.31]

8411 M6 8.0 [0.31] 14.0 [0.55]

8430K01 6-32 5.0 [0.20] 9.0 [0.35]

8430K02 M3 5.0 [0.20] 9.0 [0.35]

Integral 10-32 3.0 [0.11] 6.0 [0.24]

Table 5: Stud mounting preparation

5.4 Direct adhesive mounting

Types 8714B…, 8774B...A, 8776B...A, 8778A500 and

8778A500M14 accelerometers are designed for adhesive

mounting and require no special mounting adapters.

A cyanoacrylate type adhesive, such as Eastman 910 or

Loctite 496 super glue, is recommended. While epoxies can

also be used, cyanoacrylate adhesives provide an extremely

thin bond which provides optimal frequency response. The

surface should be clean, smooth and at in any case.

The operating temperature range for Types 8774B... and

8776B... extends to 100 °C [210 °F] and the Type 8714B…

temperature range extends to 165 °C [330 °F], which may

exceed the capabilities of the adhesive in use. Knowing

the operating temperature of the accelerometer aids in the

appropriate selection of the adhesive. Some adhesives lose

holding force at elevated temperatures. The accelerometer

could fall from the test article and experience a damaging

8714B_002-777e-10.23

Installation

Page 17

shock. Measuring information could be awed if the

accelerometer is not held in close contact to the surface

under study.

When adhesive mounting an accelerometer with a tapped

hole, make certain that no adhesive is allowed to enter the

hole. This could eventually make stud mounting dicult.

Remove the sensor with a manufacturer’s recommended

adhesive solvent. Acetone is eective for the removal of

cyanoacrylate adhesives. Use the proper sized wrench

to loosen the sensor from the adhesive mount. DO NOT

IMPACT!

When removing Types 8774B...A or 8776B...A, make sure

that the adhesive is no stronger than 600 psi when detaching

the sensor. This can be done by either the aforementioned

solvent or by increasing the temperature.

Do not attempt to remove Types 8784A5 and 8786A5 by twis-

ting with a wrench or impacting. Applying torque with a wrench

or other tools will damage the titanium housings. Remove

these accelerometers using a recommended cyanoacrylate

solvent (e.g., Loctite 768), then twist with ngers.

Care should be taken with the small mass and size of Type

8778A500 and M14 version in removal. The supplied wrench

(Type 1378) is provided to minimize the applied shock during

the process.

8714B_002-777e-10.23

Ceramic shear accelerometers

Page 18

5.5 Adapter for adhesive mounting

Type 8740A... comes with a quick locking adhesive mounting

clip Type 800M156. To install the sensor in the clip, use a thin

layer of grease between the sensor surface and clip for the

best frequency response. The sensor is "locked" into place

by turning the sensor in the clip until the sensor edges are

engaged by the clip. Figure 3 illustrates the clip mounting.

The ground isolated clip is adhesively mounted to the test

object.

Figure 3: Type 8740A… with quick locking clip (Sensitive

Axis up)

Type 8775A... uses a special adhesively mounted Delrin

Mounting Block 8475AK01 to allow the sensor to be oriented

in any direction perpendicular to the connector. This special

adapter is best used with Type 1063 Mounting Grease, or

another equivalent substance.

An adhesive mounting pad is recommended when adhesive

mounting stud-mount accelerometers. Depending on the

application, it may be desirable for screw assembly mount

accelerometers. The pad will cause some loss in high

frequency transmissibility and adds mass to the test article.

The pad is manufactured from aluminum with a hard

anodized nish. It should be secured to the test article

surface with an adhesive and then the accelerometer should

be attached to the pad with a stud. In addition to providing

a means of adhesive mounting, the mounting pad provides

ground isolation. Use pad Type 8436 for accelerometer

Types 8774B...S, 8776B...S, 8784A5 and 8786A5. Use pad

Type 8436 and 8430K stud adaptor for Type 8714B..., Use

pad Type 800M158 for Type 8740A.

5.6 Mounting with wax

Bee's wax has been used as a mounting agent for many

years. The provided Petro Wax (Kistler Type 8432 or P/N

P102 from Katt and Associates; P.O. Box 623, Zoar, Ohio

44697, or equivalent) is a good replacement for bee's wax. It

is formulated to provide improved frequency response. Wax

is a good mounting agent for lightweight sensors in temporary

installations where near room temperatures are encountered.

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Kistler 8774B100SSP Owner's manual

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Model: 8774B100SSP

Type: Owner's manual

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Kistler 8774B100SSP Owner's manual

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