HP 6920B Service Manual

OPERATION AND SERVICE MANUAL

MODEL

METER CALIBRATOR

MANUFACTURING

6920B

CODE

A

-

OPERATING

AND

SERVICE

HEWLETT

PACKARD

MANUAL

HARRISON

DIVISION

The

Hewlett-Packard

HEWLETT~PACKARD

CERTIFICATION

Company

certifies

that

this

instrument

was

thoroughly

specifications Packard

are traceable to allowedbythe

All

Hewlett-Packard

materials

the

date

in

the replace period. for consequential damages.

tested

Company

WARRANTY

and

ofdelivery, or,inthe

operating

products

No

other

and

inspected

whenitwas shipped from

further certifies

the

U.S.National

Bureau's

workmanship.

manual,

which provetobe

warranty

and

found to

the

that

its

calibration

BureauofStandardstothe

calibration facility.

AND

products

This

caseof

for

the

is expressedorimplied. We

ASSISTANCE

are

warranted

warranty

certain

specified period.

defective

applies for one major

meet

factory.

against

components

during

its

published

The

Hewlett-

measurements

extent

defects

year

\Ve

will

repair

the

warranty

are

not

in

from

listed

or

liable

For

any

assistance

Service Office..A.ddresses

contact

your

nearest

are

providedatthe

Hewlett-Packard

backofthis

Sales

manual.

and

NOTICE

These preliminary instructions t.!orliest possible deliveryofyour instrument. The Infor-

motionisnotascompleteasthot

In

the finoI yers'on of the manual. provided to Servicing Manual for this instrument reaches the proper person.

supply you with a copy of the complete manual05soon

it becomes oyoilobie.

make

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100 LOCUST

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H. J.07922

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OPERATION AND SERVICE MANUAL

MODEL

METER CALIBRATOR

MANUFACTURING

6920B

CODE

A

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October,

1:

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SPECIFICATIONS

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Input:

Output:

Line

105-125

AC

or

10V

1 rna 10 100

Regulation:

VAC,

DC.

.

01

.1V

IV

IjJ.Ci 10

jJ.Ci

100jJ.Ci

rna -

ma-

*DC

The

to

125

single

IV

-

10V

- 100V

-

1000V

-

1001JB*

- 1 rna

-

10 100 rna

-

lA

SA

only.

accuracy

VAC.

rna

phase,

to to to to

to to to to to to

specifications

58-62

5A

lA 100 rna 10

500V 500V 500V 50V 5V

.5V

rna

cps.

will

be

met

with

line

voltages

from 105

l L

L

l

L

Output

Operating

DC

Accuracy:

AC

Accuracy:

Impedance:

AC

On

Power

Temperature:

Accuracy

environment.

0.2%

0.4%

DC

- 1

100~

Other

10 100 1000

factor

of

Volt

VAC

- 1

Volt

Other

Ri'lnqe: Range:

Ranges:

VAC

of

0°

specification

output

Ranges: within

Range

Range-minimum

Range-

load

to

50oC.

.::1

Range:

Less Greater Accuracy

the

-

minimum

0.9

met

digit.

Less

Accuracy

the

listed

than

listed

to

1.0

at

than

0.0005 specification

output

0.001

than

500

specification

output

load

resistance

load

resistance

load

resistance

in

AC

+lO

o

25

ohms.

capability.

ohms.

megohms.

capability.

Ranges.

C

after1hour

is

met

5

ohms 500 50K

met

with

any

ohms ohms

warm-up

any

load

in

load

within

static

L

Overload

Grounding:

Protection:

ranges

In

voltage

In

current

May

without

ranges,

be

shorted

damage.

the

both

in

voltage

negative

terminals

terminal

i

ranges

are

and

is

grounded.

off-ground--load

open-circuited

must

in

be

current

floating.

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SECTION I

GENERAL INFORMATION

l

calibration

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from 1

'.

DC

.

AC.

L

put is

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....

racy

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l

venient

l

use

l

loads

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1-1

1-2

or

100,

power

calibrated

1-3

of

1-4

1-5

1-6 1

mv

the

shunt

DESCRIPTION

The

Model

of

volt

to

AC

at Power and

The

and

Built-in in

OPTIONAL EQUIPMENT

A

full

output

1000

line,

6920B

for

checking

all

semiconductor

voltage

0.1 output,

is

6920Bisa

meters.

1000

the

power-line

volt

is

in

terms

is

sticking

current

ranges

ohm

shunt

used,

Ten

volts

capability

ranges.

controlled

of

particularly

movements.

of

multimeters

and

is

when

the

used

source

the

feedback-regulated

continuously

and

from 100J.la

frequency;

is

The

to

RMS

useful

circuitry,

voltage

open-circuit

available

in

conjunction

impedance

from

have

AC

value

In

in

the

allows

limiting

to

2.5

output,

addition,

variable to

5A

however,

watts

while

the

correct

ofasine

for

production-line

laboratory.

for

circuits

loads

extend

with

is

0.1

full

in

the

easy

in

the

power

output

output.

the

100J.la

the

having

average

wave

wide

Compact portability.

protect

current

voltage

the

current

ohm.

source

ranges

All

range

lOA

range

the

value.

.

checking

range

the

ranges.

capabilities

particularly

are

provided,

ranges

is

not

to

10

same

construction,

ranges

waveform

The3digit

of

outputs

6920B

of

from

suited

provide

calibrated

watts

meters

downward

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in

as

output

allows

through

short

692GB.

for

ranging

either

the

for

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con-

circuit

to

When

in

10,

in-

dial

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include

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1-8

which

1-9

1-10 sional tion

1-11

1-12 a turers grounded. when the

1-14 outlet, adaptor

INSTRUMENT IDENTIFICATION

This

include

COOLING

This

dusting.

of

POWER

A

polarized

Association

plugged

power

To

manual

instrument

cooling

5-foot

three-prong

All

cable

preserve

useathree-prong

to

ground.

applies

any

differences

SYSTEM

Adequate

air.

CABLE

three

Harrison

into

conductor

(NEMA). NEMA

an

three-prong

the

only

is

convection

space

male

Laboratories

appropriate

protection

connector

to

two-prong

to

the

between

cooled

should

power

recommends

receptacle,

feature

Model

your

cable

recommended

instruments

is

adaptor

be

the

when

and

provided

is

1-1

692

instrument

ground

OB.

requires

supplied

that

are

grounds

operating

and

connect

Change

and

no

around

with

by

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instrument

equipped

the

pin.

the

sheets

this

manual.

maintenance the

unit

the

instrument

National

withapower

instrument.

instrument the

green

will

to

allow

Electrical

panel

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from a

pigtail

be

supplied

except

free

terminated

and

cabinet

cable

offset

on

for

occa-

circula-

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which,

two-prong

the

in

be

on

SECTION II

INSTALLATION

J

2-1

2-2 upon inspected. as the fications. proper to

2

2-4

It

input

2 around area

should

2-6

INCOMING

The

receipt.

scratched

carrier.

instrument

the

warranty

-3

INSTALLATION

The

is

only

and

-5

This

the

where

be

POWER REQUIREMENTS

instrument

Observe

Mechanical

panel

The

electrical

Section

page

meter

necessary

the

instrument instrument

between

calibrator

instrument

the

temperature

INSPECTION

should

surfaces,

V

includes

operation.

if

there

to

connect

is should

ISoC

be

packing

inspection

isaportable

is

ready

air

cooled.

exceeds

and

unpacked

method

involves

broken

a

It

is

any

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be

350C (590F

knobs,

involves

performance

is

recommended

electrical

power

for

operation.

Sufficient

considered

SOoC

and

inspected

and

retain

checking etc.

check

malfunction.

instrument

cable

when

(l220F).

to

9SoF).

packing

If

damage

checking

which

as

an

requiring

supplied

space

installing.

For

both

materials

for

signs

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to

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rated

mechanically

until

of

physical

is

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instrument

free

flow

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accuracy,

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electrically

unit

has

damage

fileaclaim

against

check

test.

installation.

to

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of

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temperature

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to

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power

air

in

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6920A

loaded

REPACKAGING FOR SHIPMENT

The

following

have

any

a.

b.

c.

d.

operates

is1ampere.

list

questions,

Use

the

original tainer Harrison replaceable

Wrap

the

Use and

is

the

shipping

plenty

protect

heavy

use

heavy

on

115

isageneral

contact

container designed required, Laboratories.

parts

instrument

of

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cardboard

under

carton.

packing

panel

tape

volts

guide

your

authorized

a

foam

in

or

pack

The

"Miscellaneous"

heavy

material

with

cardboard

carton

metal

60

stock

or

bands

cps.

for

and

paper

around

wooden

The

average

repackaging

Harrison

for

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container

number

or

to

plastic

all

strips.

box

seal

is

.

sides

to

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input

an

instrument

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instrument.

can

be

given

in

before

of

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house

container.

current

If

ordered

the

table

placing

instrument

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instrument

for

sales

a

new

from

it

with

shipment.

office.

con-

of

in

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output

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NOTE:

for

owner

any

number

If

service

and

correspondence,

and

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instrument

or

repair,

indicating

serial

attach

the

be

number.

is

to

a

service

sure

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tag

to

identify

shipped

to

the

or

repair

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Harrison

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to

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accomplished.

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instrument

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identifying

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model

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2-2

SECTION

OPERATION

3

-1

INTRODUCTION

III

J

3-2

allow

3-3

3

-4

3-5

3-6 should when at

these

3

-7

tipped being soon ally

3-8

larly

moved

The

6920B

one

hour

Figure

OPERATING CONTROLS

Output

This

disconnects

be

"OFF"

turning

times

When

to

either

fed

into

as

figure

returned

Always

important

with

after

3-1

Switch

on

do

all

the

pressure

to

return

the

is

ready

turning

describes

when

the

instrument.

not

other

the"

load.

"OFF"

the

in

the

output

the

changing

damage

settings

ON TEST"

is

.

output

current

still

to

use on

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output

the

are

The

switch

removed.

ranges

"ON".

as

received

to

allow

operating

terminals

loads,

This

load

made

or

the"

will

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switch

where

from

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internal

controls

when

changing

insures

or

the

operator.

and

the

ON HOLD"

return

will

remain

to

"OFF"

dangerous

that

load

to

before

the

factory.

temperature

and

indicators.

it

is

in

the

range

any

voltage

connected,

position.

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in

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removing

voltages

the

or

from

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For

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function

transients

the

In

either

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will

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stabilize.

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switch

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output

case

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position

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exist

if

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Output

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device

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positive

In

all

voltage

NOTE: point

depending

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Function

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also

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power

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(LO)

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CAUTION:

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when

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3-23

3-24 panel,

3-25

3-26 is proaching in

GENERAL OPERATING PROCEDURE

A

Overload

The

being

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various

brief

is

used.

procedure

also

load

zero

shown

should

If

excessive

for

large

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figure

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using

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Model

current

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Table

692GB

capability

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3-1list5

3-3

meter

output

the

calibrator,

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