Sine Systems RFC-1/B Instruction Book

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Disconnect

the

telephone

line

and

all

control

and

telemetry

connections

from

the

RP-8

panel.

Remove

all

ICs,

except

U5,

U8

and

U9

from

the

RFC-1

board

and

all

ICs

from

the

RP-8

panel.

Remove

them

by

inserting

a

small

screwdriver

under

alternate

ends

of

each

IC

and

gradually

pry

them

up

until

they

are

free.

Measure

the

in-circuit

values

of

R21

and

R22

and

replace

if

out-of-tolerance

or

burned.

Connect

power

to

the

system

by

means

of

the

connector

on

the

RP-8

panel.

If

resettable

fuse

Fl

opens,

disconnect

the

left

(input)

lead

(nearest

the

resettable

fuse)

of

U9,

and

one

lead

of

D5

and

D7.

Reconnect

these

leads

one

at

a

time,

replacing

anything

that

opens

the

resettable

fuse.

Measure

all

power

supply

voltages.

Using

the

heat

sink

(1/4"

spacer)

connected

to

U8

as

a

reference,

there

should

be

about

+10

volts

on

the

left

lead

of

U9,

-5.1

volts

on

the

center

lead

of

U9,

+6.9

volts

on

the

right

lead

of

U9

and

+5

volts

on

the

right

lead

of

U8.

When

the

power

supply

checks

out

OK,

set

up

a

test

meter

to

measure

the

total

AC

current

drawn

by

the

RFC-1.

The

purpose

of

this

is

to

weed

out

any

ICs

which

are

shorted

or

drawing

excessive

current.

With

nothing

but

U5

and

the

regulators

installed,

the

RFC-1

should

draw

less

than

250

milliamperes

AC

(rms)

if

the

12

volt

AC

wall

plug

transformer

is

used,

or

less

than

150

milliamperes

DC

if

a

17

volt

DC

supply

is

being

used.

Disconnect

power,

install

U6,

reconnect

power

and

note

current

flow.

Repeat

this

step

with

each

IC

on

the

RFC-1

board,

one

at

a

time,

and

replace

anything

that

causes

the

total

AC

current

to

exceed

450

milliamperes

AC

if

the

12

volt

AC

wall

plug

transformer

is

used,

or

275

milliamperes

DC

if

a

17

volt

DC

supply

is

being

used.

Then

replace

each

IC

on

the

RP-8

panel

one

at

a

time

using

the

same

technique.

The

current

supplied

to

the

RP-8

panel

can

be

checked

by

temporarily

removing

one

end

of

resettable

fuse

F2

and

connecting

a

milliammeter.

The

current

should

be

somewhere

in

the

vicinity

of

30

milliamperes

DC

with

a

telemetry

relay

selected.

The

supply

voltage

delivered

to

the

RP-8

panel

should

be

around

9.5

to

10.5

volts,

unregulated.

With

all

ICs

installed,

carefully

feel

each

component

to

determine

its

operating

temperature.

A

malfunction

could

cause

a

component

to

be

hot

enough

to

cause

a

burn

so

use

appropriate

caution.

U8,

U9

and

D6

are

normally

quite

warm.

However,

no

other

component

should

be

significantly

warm.

Replace

any

component

which

is

hot

or

significantly

warm

with

the

exception

of

U8,

U9,

or

D6.

Once

all

components

are

checked

for

normal

temperature,

begin

a

functional

test

of

the

unit.

Test

for

proper

operation

of

the

system

using

the

local

telephone

first.

If

"OK"

is

not

heard

when

the

"Local

Control"

button

is

pushed,

replace

Ul.

If

the

unit

does

not

respond

to

DTMF

tones,

replace

U2.

Command

and

telemetry

functions

are

affected

by

U6

in

the

RFC-1

and

Ul,

U2

and

U3

on

the

RP-8

panel.

If

the

telemetry

relays

are

working

and

are

feeding

a

telemetry

sample

to

the

RFC-1

but

all

readings

are

either

"Status:

On"

or

"Status:

Off',

replace

U7.

As

a

last

test,

reinstall

the

RFC-1

board

in

its

case,

connect

the

telephone

line

and

have

someone

call

to

be

sure

the

RFC-1

will

operate

from

a

remote

telephone.

Also

check

to

see

that

the

RFC-

1

does

not

cause

a

hum

on

the

telephone

line.

This

would

be

an

indication

that

one

side

of

the

telephone

line

was

shorted

to

ground

somewhere.

The

above

procedure

will

result

in

a

successful

repair

more

than

90%

of

the

time.

A

typical

lightning-damage

case

will

consist

of

R21

or

R22

open

or

damaged

with

U9

shorted

and

Ul,

U2

and

U7

damaged

or

shorted.

This

failure

mode

accounts

for

virtually

all

the

field

failures

which

have

thus

far

occurred.

More

rarely,

there

have

been

a

couple

of

cases

where

the

contacts

were

welded

shut

on

one

or

more

of

the

telemetry

selection

relays

on

an

RP-8

panel.

Lightning

Protection

Tips:

See

"Section

5

—

Installation"

3.01.1

Troubleshooting

and

Repair

page

7.7

Other manuals for Sine Systems RFC-1/B

Installation And Operation133 pages

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Sine Systems RFC-1/B Specifications

General

Brand	Sine Systems
Model	RFC-1/B
Category	Remote Control
Language	English

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