ABB MMCO-2 Manual

This manual suits for next models

6

Popular Relay manuals by other brands

Shelly

Shelly Pro Series user manual

GE

GE MVAX 11 Technical manual

Pilz

Pilz PNOZ X10 Technical instructions

Kemo Electronic

Kemo Electronic B197 quick guide

Seg

Seg MRM3 manual

Basler

Basler BE1-700C manual

CD Automation

CD Automation REVEX 2PH 280A user manual

Ruelco

Ruelco 1S04 Operation manual

Basler

Basler V3E Z1P B2C1F instruction manual

Doepke

Doepke Dupline DSM 2 operating instructions

Siemens

Siemens SIRIUS 3RT1966-4D Original operating instructions

GE

GE DGP instruction manual

Kyongbo Electronics

Kyongbo Electronics GDR-D01 user manual

Siemens

Siemens SIPROTEC 4 user manual

Siemens

Siemens BD2-AK03X/FS Series installation instructions

Leuze

Leuze MSI-SR5B Original operating instructions

Littelfuse

Littelfuse SE-330AU manual

EVA Logik

EVA Logik ZW12 user manual

Instruction

Leaflet

JL

llll

Mil

*

ABB

Power

T

&

D

Company

Inc

.

Relay

Division

Allentown

,

PA

18106

I

.

L

.

41

-

121.2

Type

MMCO

Multi

-

Phase

Overcurrent

Relay

Effective

:

August

,

1996

Supersedes

Preliminary

I

.

L

.

41

-

121.1

Dated

June

,

1993

must

be

practiced

when

handling

printed

cir

-

cuit

boards

and

components

.

Use

of

anti

-

static

handling

materials

and

grounding

pro

-

cedures

is

required

.

Before

putting

relay

into

service

,

remove

all

blocking

which

may

have

been

inserted

for

the

purpose

of

securing

the

parts

during

shipment

.

Operate

the

relay

to

check

the

set

-

tings

and

electrical

contacts

.

The

operation

of

this

relay

is

based

on

ABB

proprietary

software

,

resident

-

in

-

memory

components

.

Purchase

of

this

relay

includes

a

restrictive

license

for

the

use

of

any

and

all

programs

solely

as

part

of

the

protective

functions

.

ABB

reserves

the

right

to

request

return

of

the

memory

components

should

the

relay

no

longer

be

used

as

a

protective

device

.

The

programs

may

not

be

copied

,

transferred

or

applied

to

any

other

device

.

TABLE

OF

CONTENTS

Page

Section

1

Application

2

Construction

3

Characteristics

4

Settings

5

Operation

6

Circuit

Description

..

..

7

Acceptance

Test

8

Adjustments

9

Installation

10

Maintenance

and

Repair

11

Renewal

Parts

-

List

of

Figures

-

Catalog

Numbers

1

2

4

7

8

11

13

14

14

15

15

16

.

42

1

.

APPLICATION

CAUTION

The

MMCO

is

a

multi

-

phase

(

2

or

3

phase

)

and

ground

,

time

and

instantaneous

ac

overcurrent

relay

(

see

Block

Diagram

,

Figure

1

)

.

It

is

used

to

sense

a

current

level

above

a

particular

setting

and

to

trip

a

circuit

breaker

to

clear

faults

.

A

wide

range

of

time

-

current

characteristics

permit

applications

involving

fuses

,

reclosers

,

cold

-

load

pickup

,

and

motor

start

-

ing

,

in

addition

to

essentially

fixed

-

time

applications

.

Typical

applications

of

the

MMCO

relay

are

described

,

in

Table

1

,

with

respect

to

familiar

CO

or

IEC

equivalents

.

It

is

recommended

that

the

user

of

this

equip

-

ment

become

acquainted

with

the

information

in

this

instruction

leaflet

before

energizing

the

relay

.

Failure

to

do

so

may

result

in

injury

to

personnel

or

damage

to

the

equipment

,

and

may

affect

the

equipment

warranty

.

The

relay

contains

static

sensitive

components

.

Electrostatic

Discharge

(

ESD

)

precautions

All

possible

contingencies

which

may

arise

during

installation

,

operation

or

maintenance

,

and

all

details

and

variations

of

this

equipment

do

not

purport

to

be

covered

by

these

instructions

.

If

further

information

is

desired

by

purchaser

regarding

this

particular

installation

,

operation

or

maintenance

of

this

equipment

,

the

local

ABB

Power

T

&

D

Company

Inc

.

representative

should

be

contacted

.

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

TABLE

1

:

MMCO

APPLICATIONS

RELATED

TO

INVERSE

TIME

CURVES

TYPICAL

APPLICATIONS

DESCRIPTION

CURVE

TYPE

1

)

Differential

protection

where

saturation

of

current

transformers

is

not

expected

,

or

where

insensitive

setting

and

delayed

tripping

is

permissible

.

2

)

Overcurrent

protection

,

phase

or

ground

,

where

coordination

with

downstream

devices

is

not

involved

and

2

to

60

cycle

trip

-

ping

is

allowable

.

MMCO

-

2

Short

Motor

-

locked

rotor

protection

where

allowable

locked

rotor

time

is

approximately

between

10

and

70

seconds

.

MMCO

-

5

Long

Overcurrent

protection

where

coordination

with

downstream

devices

is

not

involved

and

MMCO

-

2

is

too

fast

.

The

operating

time

of

this

relay

does

not

vary

greatly

as

current

level

varies

.

MMCO

-

6

Definite

1

)

Overcurrent

protection

where

coordination

with

other

devices

is

required

,

and

generation

varies

.

2

)

Backup

protection

for

relays

on

other

circuits

.

MMCO

-

7

(

IEC

-

A

)

Moderately

MMCO

-

8

Inverse

MMCO

-

9

(

IEC

-

B

)

Very

Inverse

Motor

protection

where

allowable

locked

rotor

time

is

less

than

10

seconds

.

Overcurrent

protection

where

coordination

with

fuses

and

reclos

-

ers

is

involved

,

or

where

cold

-

load

pickup

or

transformer

inrush

are

factors

.

MMCO

-

11

(

IEC

-

C

)

Extremely

Inverse

display

•

Read

data

for

pervious

16

fault

cases

(

tar

-

gets

)

.

•

Make

all

settings

using

password

entry

.

The

following

types

of

INCOM

devices

are

available

:

Options

are

provided

for

a

real

-

time

clock

and

exter

-

nal

directional

control

.

An

external

3

-

phase

device

(

e

.

g

.

,

KD

-

10

or

H

3

)

is

required

to

supervise

phase

tripping

,

and

a

single

ground

directional

unit

(

e

.

g

.

,

KRC

,

KRP

or

KRD

)

is

required

to

supervise

ground

tripping

.

When

this

option

is

included

and

selected

as

being

operative

,

timing

will

not

start

until

the

external

contact

closes

.

An

alternate

option

allows

resetting

to

be

accomplished

externally

(

without

using

the

com

-

munication

channel

)

,

but

only

when

directional

con

-

trol

is

not

supplied

.

Options

for

current

are

as

follows

:

•

INCOM

PONI

(

to

access

MMCO

relay

through

INCOM

network

)

•

RS

-

232

PONI

(

to

access

MMCO

relay

through

RS

-

232

lines

)

2

.

CONSTRUCTION

•

3

PH

Ground

•

3

PH

No

Ground

•

2

PH

Ground

The

MMCO

is

a

microprocessor

-

based

relay

consist

-

ing

of

5

printed

circuit

modules

which

are

packaged

in

a

standard

FT

-

22

flexitest

case

(

see

Figure

2

)

.

Refer

to

I

.

L

.

41

-

076

for

detailed

information

on

the

FT

-

22

case

.

The

5

modules

are

as

follows

(

see

Section

6

CIRCUIT

DESCRIPTIONS

)

:

An

INCOM

communications

device

may

be

pur

-

chased

separately

to

allow

for

access

to

the

MMCO

relay

,

using

an

access

code

.

•

Power

Supply

•

Current

Transformer

(

ct

)

•

Microprocessor

•

Display

The

following

remote

operations

may

be

performed

using

an

INCOM

communications

device

:

•

Read

all

information

available

on

front

panel

2

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

2.5

.

DISPLAY

MODULE

•

Input

/

Output

(

I

/

O

)

The

Display

module

includes

(

see

Figure

3

)

:

2.1

.

POWER

SUPPLY

The

Power

Supply

is

available

in

two

versions

:

48

to

125

Vdc

or

250

Vdc

.

The

Power

Supply

module

con

-

tains

components

of

a

dc

/

dc

converter

,

an

ABB

cus

-

tom

linear

IC

,

a

+

5

Volt

reference

and

adjustment

potentiometers

for

the

+

5

V

reference

,

dc

/

dc

con

-

verter

converts

48

-

125

Vdc

or

250

Vdc

to

21

Vdc

and

5

Vdc

.

A

16

x

2

character

alphanumeric

LCD

for

display

of

the

last

four

trip

targets

,

settings

,

metering

,

relay

cat

-

alog

number

,

software

versions

,

and

time

and

date

(

optional

)

.

A

red

“

TRIP

”

LED

which

blinks

when

input

current

is

above

time

-

delay

pickup

level

;

is

steady

for

time

-

delay

or

instantaneous

trip

;

and

seals

-

in

when

breaker

trip

current

flow

is

detected

.

2.2

.

CURRENT

TRANSFORMER

(

CT

)

The

ct

module

contains

a

current

transformer

for

each

phase

and

ground

input

,

as

well

as

input

wave

-

form

conditioning

and

surge

protection

.

Ct

module

outputs

are

sent

to

the

Microprocessor

module

.

An

amber

“

MONITOR

”

LED

which

is

“

ON

”

during

nor

-

mal

relay

operation

,

for

power

-

on

and

self

-

check

indi

-

cation

.

This

LED

will

be

“

OFF

”

if

there

is

a

relay

hardware

failure

or

alarm

condition

.

2.3

.

MICROPROCESSOR

The

Microprocessor

module

contains

a

microcom

-

puter

chip

which

includes

an

analog

to

digital

(

A

/

D

)

converter

,

input

and

output

ports

and

timers

.

The

module

also

includes

memory

,

a

real

-

time

clock

(

optional

)

.

Relay

pickup

calibration

is

part

of

this

module

,

as

well

as

a

trimmer

capacitor

for

adjust

-

ment

of

the

optional

real

-

time

clock

.

There

are

five

keypad

push

-

buttons

as

follows

:

1

)

“

SELECT

”

button

(

SW

1

)

.

Selects

between

the

settings

mode

,

targets

dis

-

play

,

time

setting

and

metering

display

.

2

)

“

SCROLL

”

button

(

SW

2

)

.

Accesses

the

different

categories

within

each

mode

.

3

&

4

)

“

RAISE

”

(

SW

3

)

and

“

LOWER

”

(

SW

4

)

buttons

.

Select

the

actual

value

of

the

parameter

in

the

settings

mode

.

When

“

RAISE

”

or

“

LOWER

”

has

been

pushed

,

it

is

not

possible

to

“

SELECT

”

or

“

SCROLL

”

new

parameters

without

pushing

“

ENTER

”

first

.

2.4

.

INPUT

/

OUTPUT

The

INPUT

/

OUTPUT

module

contains

contact

clo

-

sure

outputs

and

optically

isolated

inputs

.

A

reed

relay

detects

the

trip

current

flow

through

trip

con

-

tacts

.

2.4

.

1

.

Contact

Closure

Outputs

(

See

Section

6.6

)

(

TDTRIP

)

(

ITRIP

)

(

TDANUNLO

)

(

IANUNLO

)

(

ALARMLO

)

5

)

“

ENTER

”

button

(

SW

8

)

.

Relay

accepts

the

setting

which

is

shown

on

the

alphanumeric

display

.

In

addition

,

there

are

three

other

external

buttons

that

are

activated

as

follows

:

Time

Delay

Trip

Instantaneous

Trip

Time

Delay

Annunciator

Instantaneous

Annunciator

Alarm

Output

2.4

.

2

.

Optically

-

Isolated

Inputs

(

w

/

Directional

Control

Option

)

Phase

Directional

Control

Ground

Directional

Control

“

EXTERNAL

SCROLL

”

button

(

SW

7

)

.

Can

be

pushed

without

opening

the

relay

case

.

This

button

scrolls

the

display

.

“

TARGET

RESET

button

(

SW

6

)

.

Can

be

reset

without

opening

the

relay

case

.

This

button

resets

the

trip

LED

if

the

trip

LED

has

been

sealed

-

in

by

breaker

trip

current

flow

.

All

target

information

(

16

targets

stored

in

the

relay

)

1

.

(

TCP

)

(

TCG

)

2

.

2.4

.

3

.

Optically

-

isolated

Inputs

(

w

/

Remote

Reset

Option

)

Remote

Reset

(

RR

)

3

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

outputs

except

the

Alarm

output

(

2.4

above

)

.

A

pen

or

other

slender

object

is

required

to

push

this

button

(

prevents

accidental

activation

)

.

may

be

erased

by

pushing

this

button

for

6

sec

-

onds

.

3

.

“

TRIP

TEST

”

button

(

SW

5

)

.

This

button

causes

the

relay

to

trip

,

activating

all

3

.

CHARACTERISTICS

Meets

all

applicable

ANSI

C

37.90

and

IEC

255

stds

.

Standards

-

20

to

+

55

deg

.

C

(

operating

)

-

40

to

+

70

deg

.

C

(

storage

)

Temperature

Range

50

Hz

or

60

Hz

(

selectable

)

Frequency

Time

Delay

Pickup

Settings

5

Amp

ct

0.5

Amps

to

12

Amps

in

1

.

Amp

steps

01

Amps

to

2.4

Amps

in

.

01

Amp

steps

1

Amp

ct

5

%

for

TD

setting

5

%

for

IT

setting

Pickup

Accuracy

Seven

sets

of

time

curves

from

CO

-

2

to

CO

-

11

.

Each

set

includes

63

curves

.

(

See

Table

2

and

Figures

4

thru

10

)

inverse

Curves

(

U

.

S

.

A

.

version

)

Three

sets

of

time

curves

,

IEC

-

A

,

IEC

-

B

and

IEC

-

C

.

Each

set

includes

63

curves

.

(

See

Table

3

and

Figures

11

thru

13

.

)

Inverse

Curves

(

IEC

version

)

At

5

times

pickup

10

%

or

3

cycles

whichever

is

greater

A

At

20

times

pickup

10

%

or

3

cycles

whichever

is

greater

A

A

NOTE

:

10

ms

pickup

time

must

be

added

to

curves

for

TDTRIP

output

relay

.

Timing

Accuracy

Dropout

Ratio

(

Time

delay

&

Inst

,

contacts

)

98

%

Min

.

TRIP

Reset

Time

2.5

cycles

typical

3.5

cycles

max

.

.

5

A

dc

current

minimum

required

thru

TRIP

contact

circuits

to

Seal

-

in

TRIP

con

-

tacts

and

TRIP

LED

TRIP

Seal

-

In

Current

Pickup

(

with

5

Amp

ct

)

:

1

Amp

to

127

Amps

in

1

Amp

steps

.

Instantaneous

Unit

Pickup

(

with

1

Amp

ct

)

:

0.2

Amps

to

25.5

Amps

in

.

1

Amp

steps

.

Pickup

Settings

Maximum

Pickup

time

:

1.5

cycles

@

current

=

3

x

pickup

2

cycles

@

current

=

2

x

instantaneous

setting

4

cycles

@

current

=

1.2

x

instantaneous

setting

Trip

Contacts

N

.

O

.

contact

for

time

delay

trip

N

.

O

.

contact

for

instantaneous

trip

N

.

C

.

contact

(

contact

closed

if

loss

of

power

or

self

-

check

failure

)

Alarm

Contact

Annunciator

Contacts

N

.

O

.

contact

for

time

delay

trip

N

.

O

.

contact

for

instantaneous

trip

4

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

CHARACTERISTICS

,

cont

’

d

.

Make

:

30

Amp

at

250

Vdc

for

1

sec

(

one

shot

)

Break

:

50

W

Resistive

up

to

250

Vdc

Contact

Rating

One

input

requires

battery

voltage

to

enable

phase

tripping

.

Second

input

requires

battery

voltage

to

enable

ground

tripping

.

Directional

control

can

be

enabled

or

bypassed

on

any

combination

of

the

four

Trip

Units

(

<

J

>

-

TC

,

<

|

)

-

!

NST

,

GRND

-

TOC

,

GRND

-

INST

)

via

settings

with

this

option

.

Directional

Control

(

Option

)

Input

which

causes

reset

of

sealed

-

in

trip

LED

when

battery

voltage

is

applied

to

it

.

Remote

Reset

(

Option

)

Targets

are

dated

and

time

-

tagged

.

Current

date

and

time

can

also

be

read

.

(

Uses

lithium

battery

backup

.

)

Real

-

time

Clock

(

Option

)

DC

Power

Drain

8

Watts

max

.

10

Watts

max

.

Operating

Voltage

38

-

140

Vdc

200

-

280

Vdc

Nominal

Voltage

DC

Power

Supply

48

/

125

Vdc

250

Vdc

1

Second

Rating

200

Amps

100

Amps

OHMIC

Burden

Continuous

Rating

16

Amps

5

Amps

ct

Type

5

A

ct

1

Act

AC

Ratings

.

005

O

.

025

0

.

Table

3

:

IEC

(

CO

)

TYPE

TIME

CURVE

CALIBRATION

POINTS

Table

2

:

USA

(

CO

)

TYPE

TIME

CURVE

CALIBRATION

POINTS

OPERATING

TIME

CURVE

TYPE

TIME

CURRENT

APPLIED

TIMES

P

/

U

VALUE

OPERATING

TIME

CURVE

TYPE

TIME

CURRENT

APPLIED

TIMES

P

/

U

VALUE

DIAL

DIAL

IN

IN

SECONDS

SECONDS

A

30

5

x

2.038

1.080

MMCO

-

2

5

X

0.352

0.188

30

20

x

20

X

B

5

X

1.607

0.338

5

X

14.693

12.186

30

MMCO

-

5

30

20

X

10

X

C

5

X

5

X

30

1.587

0.095

MMCO

-

6

1.201

1.025

30

20

X

10

X

NOTE

:

10

milliseconds

pickup

time

for

the

TD

relay

must

be

added

to

the

above

operate

times

for

total

operate

time

of

the

MMCO

relay

.

5

X

MMCO

-

7

30

1.585

0.859

20

X

MMCO

-

8

5

X

1.979

0.872

30

20

X

MMCO

-

9

5

X

30

1.331

0.572

20

X

MMCO

-

11

5

X

1.226

0.195

30

20

X

NOTE

:

10

msec

pickup

time

,

for

the

TD

relay

,

must

be

added

to

the

above

operate

times

for

total

MMCO

relay

operate

time

.

5

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

1

.

Transformer

inrush

2

.

Capacitor

inrush

3

.

Faults

having

magnitudes

associated

with

loca

-

tions

at

or

beyond

the

next

protective

device

.

Consideration

must

be

given

to

the

added

effect

of

dc

offset

in

the

phenomenon

listed

.

In

general

,

a

setting

of

120

%

of

the

symmetrical

current

(

no

dc

offset

present

)

will

provide

adequate

security

.

4

.

SETTINGS

4.1

.

TIME

OVERCURRENT

FUNCTION

The

level

and

time

settings

are

dictated

by

those

nor

-

mal

system

phenomena

which

must

be

ignored

,

and

by

the

minimum

current

the

system

is

expected

to

deliver

to

a

fault

in

the

protected

zone

of

the

relay

.

For

the

phase

units

,

pick

up

and

time

settings

must

be

chosen

with

due

consideration

given

to

such

long

or

moderate

time

phenomena

as

:

4.3

.

INVERSE

TIME

CURVES

The

MMCO

relay

simulates

the

traditional

inverse

curve

sets

(

USA

or

IEC

version

)

,

which

are

perma

-

nently

stored

in

memory

.

1

.

Maximum

load

2

.

Cold

-

load

pickup

3

.

Motor

starting

Pickup

and

time

settings

above

any

of

these

influenc

-

ing

factors

must

be

chosen

.

Coordination

with

other

devices

must

also

be

achieved

.

A

time

of

0.3

sec

-

onds

plus

breaker

time

is

generally

recommended

as

a

coordinating

time

interval

(

CTI

)

between

adjacent

relays

being

coordinated

.

With

careful

evaluation

of

current

transformer

errors

,

setting

accuracy

and

worst

case

relay

errors

,

a

lower

CTI

may

be

used

.

4.3

.

1

.

USA

Version

/

CO

Curves

There

are

seven

families

of

CO

curves

:

1

.

MMCO

-

2

-

Short

Inverse

2

.

MMCO

-

5

-

Long

Inverse

3

.

MMCO

-

6

-

Definite

Inverse

4

.

MMCO

-

7

-

Moderate

Inverse

5

.

MMCO

-

8

-

Standard

Inverse

6

.

MMCO

-

9

-

Very

Inverse

7

.

MMCO

-

11

-

Extreme

Inverse

Where

a

ground

setting

is

chosen

,

attention

should

be

given

to

:

Each

family

contains

63

curves

determined

by

the

time

dial

setting

(

see

Figures

4

thru

10

)

.

The

expres

-

sions

for

the

CO

curves

are

shown

in

equation

(

1

)

for

l

/

IO

greater

than

1.5

per

unit

,

and

equation

(

2

)

for

l

/

IO

between

1.0

and

1.5

per

unit

.

1

.

Maximum

residual

load

unbalance

2

.

Loss

of

largest

single

-

phase

load

(

for

example

,

as

a

result

of

fuse

-

blowing

)

Pickup

for

ground

sensing

should

be

set

at

a

current

level

above

these

conditions

.

Time

delay

for

ground

tripping

should

be

set

to

coordinate

with

other

devices

.

T

=

[

To

+

K

/

(

l

/

IO

-

C

)

P

]

x

D

/

24

,

000

T

=

[

R

/

(

1

/

10

-

1.0

)

]

x

D

/

24

,

000

trip

time

in

seconds

definite

time

term

input

current

pickup

current

settings

scale

factor

for

the

basic

inverse

time

a

constant

a

constant

an

exponent

determining

the

inversions

time

dial

setting

from

1

to

63

(

1

)

(

2

)

where

T

To

I

Curve

shapes

may

be

chosen

independently

for

the

phase

and

ground

functions

.

A

single

setting

estab

-

lishes

the

curve

shape

for

the

2

(

or

3

)

phases

.

•

o

=

K

C

4.2

.

INSTANTANEOUS

OVERCURRENT

FUNC

-

TION

R

P

The

instantaneous

settings

must

be

chosen

to

be

above

:

D

6

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

5

.

OPERATION

Table

4

indicates

all

values

of

pre

-

determined

param

-

eters

(

To

,

K

,

C

,

P

and

R

)

in

the

program

for

each

curve

.

Parameters

l

0

and

D

are

user

-

selectable

via

pickup

setting

and

time

dial

switches

,

respectively

.

The

MMCO

relay

continually

executes

its

protective

functions

whenever

DC

power

is

applied

to

the

relay

.

Concurrently

with

this

protective

function

,

four

modes

may

be

selected

using

the

front

panel

keypad

switches

.

Table

4

:

TIME

CURVE

PARAMETERS

c

CURVE

K

P

R

To

The

modes

are

:

MMCO

-

2

MMCO

-

5

MMCO

-

6

MMCO

-

7

MMCO

-

8

MMCO

-

9

MMCO

-

11

735

0.675

1.130

1.190

0.800

1.270

1.350

0.500

1

510

112

13769

1

22705

8197

•

Metering

•

Settings

•

Targets

Set

Time

(

Only

with

optional

real

-

time

clock

)

671

1

1475

785

2491

3121

1

525

9200

478

4122

2756

17640

1

9342

310

1

110

2

8875

4.3

.

2

.

IEC

Curves

In

addition

to

the

keypad

switches

which

select

the

relay

modes

,

there

are

three

switches

accessible

from

the

front

panel

dedicated

to

special

functions

.

There

are

three

families

of

IEC

curves

;

IEC

-

A

,

IEC

-

B

,

IEC

-

C

.

Each

family

contains

63

curves

determined

by

the

time

dial

setting

(

see

Figures

11

thru

13

)

.

The

expression

for

the

IEC

curves

is

shown

in

the

equa

-

tion

(

3

)

below

:

These

functions

are

:

•

TRIP

TEST

•

TARGET

RESET

•

EXTERNAL

SCROLL

A

flow

chart

for

MMCO

relay

keypad

operation

is

included

(

Figure

16

)

for

reference

.

T

=

(

K

x

D

/

63

)

/

[

G

/

Gs

)

a

-

1

]

(

3

)

(

3

)

where

T

=

Theoretical

operating

time

(

seconds

)

K

=

constant

characterizing

the

relay

(

seconds

)

D

=

time

dial

setting

from

1

to

63

G

=

value

of

the

characteristic

quantity

(

i

.

e

.

,

current

through

relay

ct

)

.

Gs

=

setting

value

of

characteristic

quantity

(

i

.

e

.

,

pickup

setting

)

a

=

index

characterizing

the

algebraic

function

5.1

.

METERING

MODE

(

“

M

”

IN

UPPER

LEFT

CORNER

OF

DISPLAY

)

When

dc

power

is

applied

to

the

relay

it

displays

the

metering

mode

with

IA

,

IB

,

and

S

(

status

)

appearing

on

the

front

panel

.

When

the

relay

is

not

in

the

Meter

-

ing

Mode

the

“

SELECT

”

button

can

be

used

to

go

to

this

mode

.

The

following

additional

information

can

be

displayed

using

the

scroll

button

:

IC

,

I

0

,

and

with

the

real

time

clock

option

:

day

,

date

and

time

.

The

following

values

are

used

for

a

and

K

:

When

in

the

Metering

Mode

,

the

status

,

“

S

”

,

appears

in

the

upper

right

hand

corner

of

the

display

.

When

there

is

an

internal

hardware

or

software

failure

in

the

relay

the

amber

MONITOR

LED

goes

out

and

the

value

of

the

status

indicates

the

cause

of

the

failure

.

The

meaning

of

the

status

coded

(

S

=

““

)

are

as

fol

-

lows

:

Very

Inverse

Time

(

B

)

Extreme

Inverse

Time

(

C

)

Standard

Inverse

Time

(

A

)

K

0.14

13.5

80.0

1.0

0.02

2.0

a

7

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

The

available

curves

are

listed

in

Table

1

and

graphed

in

Figures

4

-

13

.

Time

dials

range

from

1

to

63

for

each

curve

type

.

The

available

time

and

instantaneous

pickup

settings

and

frequency

settings

are

listed

in

section

3

(

Characteristics

)

.

EEPROM

RAM

EPROM

A

/

D

S

=

00

S

=

01

S

=

02

S

=

03

S

=

04

S

=

05

S

=

06

S

=

07

S

=

08

S

=

09

S

=

10

S

=

11

S

=

12

S

=

13

S

=

14

S

=

15

pass

pass

pass

pass

pass

pass

pass

pass

pass

pass

pass

pass

pass

pass

pass

fail

fail

pass

fail fail

fail

pass

pass

pass

Directional

control

inputs

are

available

as

an

option

.

With

this

option

,

directional

control

inputs

for

phase

and

ground

instantaneous

and

time

delay

tripping

may

be

selected

using

the

settings

mode

.

For

exam

-

ple

,

when

phase

time

delay

directional

control

has

been

selected

,

battery

positive

voltage

must

be

applied

to

relay

terminal

18

and

battery

negative

volt

-

age

to

terminal

20

(

Figure

17

)

in

order

to

enable

phase

time

delay

tripping

.

When

ground

instanta

-

neous

directional

control

has

been

selected

,

battery

positive

voltage

must

be

applied

to

terminal

19

and

battery

negative

voltage

to

terminal

20

in

order

to

enable

ground

instantaneous

tripping

.

fail fail

fail

fail

pass

fail fail

fail

fail

pass

pass pass

pass

pass

pass

pass

fail

fail

fail

fail

pass

fail

fail

fail

fail

fail

pass

pass pass

fail

fail

fail

fail

fail

fail

pass

fail

fail

fail

fail

5.2

.

SETTINGS

MODE

(

“

S

”

IN

UPPER

LEFT

CORNER

OF

DISPLAY

)

This

mode

is

selected

by

pushing

the

“

SELECT

”

but

-

ton

.

Initially

the

software

“

Version

#

"

appears

on

the

display

.

Using

the

“

SCROLL

”

button

the

following

set

-

tings

may

be

selected

:

The

directional

control

option

settings

are

:

Directional

Control

Display

None

Grnd

.

T

.

D

.

Grnd

.

Inst

.

Grnd

.

Inst

.

&

T

.

D

.

Ph

.

T

.

D

.

Ph

.

Inst

.

Ph

.

Inst

.

&

T

.

D

.

Ph

.

Inst

.

&

Grnd

.

T

.

D

.

Ph

.

Inst

&

Grnd

.

Inst

.

Ph

.

Inst

&

Grnd

.

Inst

.

&

T

.

D

.

Ph

.

T

.

D

.

&

Grnd

.

T

.

D

.

Ph

.

T

.

D

.

&

Grnd

.

Inst

.

Ph

.

T

.

D

.

&

Grnd

.

Inst

.

&

T

.

D

.

Ph

.

Inst

.

&

T

.

D

.

&

Grnd

.

T

.

D

.

Ph

.

Inst

.

&

T

.

D

.

&

Grnd

.

Inst

.

Ph

.

Inst

.

&

T

.

D

.

&

Grnd

.

Inst

.

&

T

.

D

.

G

T

PHASE

PICKUP

GRND

PICKUP

PHASE

INST

.

GROUND

INST

.

PH

TIME

DIAL

GRND

TIME

DIAL

OPTION

(

not

changeable

)

PHASE

CURVE

GROUND

CURVE

FREQUENCY

DIR

CONTROL

(

only

with

directional

control

option

)

INCOM

KEY

(

for

use

with

INCOM

accessories

)

MMCO

RELAY

VERSION

#

Gl

GIT

P

T

PI

PIT

PI

_

G

_

T

PI

_

GI

_

PLGIT

P

_

TG

_

T

P

_

TGI

_

P

_

T

GIT

PIT

G

_

T

PIT

Gl

_

PIT

GIT

The

directional

control

settings

are

selected

using

the

raise

and

lower

buttons

when

in

the

“

DIR

CON

-

TROL

”

settings

mode

.

When

the

relay

is

in

one

of

the

above

setting

modes

,

the

value

of

the

setting

can

be

changed

using

the

raise

or

lower

buttons

.

Once

the

value

of

the

setting

has

been

changed

,

the

“

ENTER

”

button

must

be

pushed

before

the

relay

can

be

scrolled

to

the

next

setting

.

The

“

ENTER

”

button

also

causes

the

relay

to

accept

the

new

setting

.

The

INCOM

key

setting

allows

the

INCOM

key

num

-

ber

to

be

changed

to

an

integer

between

0

and

255

.

This

key

is

required

to

access

the

relay

through

a

8

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

ues

to

keep

time

when

power

has

been

removed

from

the

relay

although

the

display

goes

blank

.

communications

network

.

If

the

communications

option

is

not

being

used

,

the

INCOM

key

setting

should

be

ignored

.

5.5

.

TRIP

TEST

FUNCTION

The

“

TRIP

TEST

”

push

-

button

switch

is

located

in

the

upper

right

corner

of

the

front

panel

.

It

is

used

to

test

the

trip

and

annunciator

outputs

to

the

relay

.

When

this

switch

is

pushed

,

the

time

delay

and

instanta

-

neous

trip

and

annunciator

output

contacts

close

and

the

trip

LED

goes

on

.

The

test

trip

data

is

saved

and

displayed

as

“

T

1

”

in

the

same

manner

as

an

overcur

-

rent

trip

The

TRIP

LED

will

remain

on

(

Seal

in

)

if

there

was

current

flow

through

the

trip

contacts

.

A

slender

object

such

as

a

pen

is

required

to

push

the

“

TRIP

TEST

”

switch

.

This

prevents

accidental

trip

-

ping

of

the

MMCO

relay

.

5.3

.

TARGETS

MODE

(

“

T

”

IN

UPPER

LEFT

CORNER

OF

DISPLAY

)

The

Targets

(

trip

data

)

for

the

previous

four

faults

(

“

T

1

”

to

“

T

4

”

)

can

be

displayed

by

pushing

the

“

SELECT

”

push

-

button

.

Data

for

the

previous

16

faults

can

be

read

remotely

if

the

communications

option

is

used

.

The

“

SCROLL

”

button

is

used

to

scroll

through

the

data

for

each

target

,

displaying

the

following

informa

-

tion

:

Type

of

trip

:

Phase

or

Grnd

.

&

Inst

,

or

Time

Delay

5.6

.

TARGET

RESET

FUNCTION

The

“

TARGET

RESET

”

push

-

button

switch

is

located

in

the

lower

right

corner

of

the

relay

front

panel

.

An

external

lever

makes

the

“

TARGET

RESET

”

switch

accessible

when

relay

case

is

closed

.

When

breaker

trip

current

flow

is

detected

by

the

MMCO

,

the

“

TRIP

”

LED

is

sealed

in

(

remains

on

after

overcurrent

is

removed

)

.

The

sealed

in

LED

is

extinguished

by

pushing

the

‘

TARGET

RESET

”

switch

.

If

this

switch

is

held

in

the

on

position

for

6

seconds

,

all

target

information

(

T

1

-

T

16

)

is

erased

.

•

Current

at

trip

time

:

IA

,

IB

,

IC

,

I

0

•

Time

of

trip

(

option

)

:

Day

,

Date

,

Time

If

the

relay

is

not

in

the

settings

mode

,

the

display

will

jump

to

the

most

recent

trip

data

(

T

1

)

when

a

trip

occurs

.

In

order

to

ensure

proper

fault

cur

-

rent

target

data

,

the

fault

current

must

remain

for

a

minimum

of

three

cycles

and

at

least

1

cycle

after

trip

.

For

times

less

than

this

,

the

fault

current

level

displayed

will

be

lower

than

the

actual

.

NOTE

:

With

the

remote

reset

option

,

the

sealed

in

trip

LED

may

be

reset

(

extinguished

)

remotely

.

To

reset

the

trip

LED

remotely

,

battery

positive

voltage

must

be

applied

to

relay

terminal

18

and

battery

negative

volt

-

age

to

terminal

20

(

Figure

17

)

.

The

remote

reset

will

not

reset

relay

target

information

available

on

the

LCD

display

.

5.4

.

SET

TIME

MODE

(

ONLY

WITH

OPTIONAL

REAL

-

TIME

CLOCK

)

(

“

ST

”

in

upper

left

corner

of

display

.

)

5.7

.

EXTERNAL

SCROLL

FUNCTION

The

“

EXTERNAL

SCROLL

”

push

-

button

switch

is

located

in

the

lower

left

corner

of

the

relay

front

panel

.

An

eternal

lever

makes

the

“

EXTERNAL

SCROLL

”

switch

accessible

when

relay

case

is

closed

.

When

held

in

the

on

position

,

this

switch

scrolls

the

display

through

all

relay

information

(

Soft

-

ware

Version

Number

,

Settings

,

Relay

Style

Number

,

Target

Information

,

Metering

,

Time

)

.

When

the

“

EXTERNAL

SCROLL

”

switch

is

released

,

the

relay

The

Set

Time

mode

can

be

accessed

by

pushing

the

“

SELECT

”

button

.

Once

in

this

mode

,

the

“

SCROLL

’

button

is

used

to

select

which

parameter

is

to

be

changed

:

day

of

week

,

month

,

day

,

year

,

hour

(

24

hour

clock

)

,

minute

,

second

.

The

value

of

each

parameter

is

changed

using

the

“

RAISE

”

or

“

LOWER

”

button

to

start

it

running

.

When

the

“

ENTER

”

button

has

been

pushed

the

relay

display

goes

to

the

metering

Mode

,

displaying

the

clock

infor

-

mation

(

Day

,

Date

,

Time

)

.

The

real

-

time

clock

contin

-

9

Courtesy of NationalSwitchgear.com

I

.

L

.

41

-

121.2

(

Power

Supply

Module

Internal

Schematic

Figure

22

)

which

is

controlled

by

the

microprocessor

U

2

.

The

ranging

chip

multiplexes

the

phase

and

ground

inputs

.

Op

amp

U

1.2

,

and

associated

resistors

allow

for

calibration

of

the

high

level

input

voltage

to

the

microprocessor

.

The

calibration

is

made

by

adjusting

potentiometer

P

1

so

that

the

relay

pickup

and

meter

-

ing

are

correct

with

the

input

current

set

to

4

amps

or

greater

(

0.8

A

or

greater

with

the

1

A

ct

)

.

remains

in

the

display

mode

which

it

was

in

when

the

“

EXTERNAL

SCROLL

"

switch

was

released

.

Settings

cannot

be

changed

using

the

“

EXTERNAL

SCROLL

”

button

.

6

.

CIRCUIT

DESCRIPTION

Documents

referenced

are

:

•

Current

Transformer

Module

Internal

Sche

-

matic

(

Figure

18

)

•

Microprocessor

Module

Internal

Schematic

(

Figure

20

)

•

Power

Supply

Module

Internal

Schematic

(

Figure

22

)

•

Display

Module

Internal

Schematic

(

Figure

Referring

to

Power

Supply

Module

Internal

Sche

-

matic

,

Figure

22

:

A

5

-

volt

voltage

reference

for

the

A

/

D

converter

and

for

the

5

volt

power

supply

is

generated

by

voltage

reference

Z

6

,

Op

amp

U

2.1

and

associated

discrete

components

.

24

)

•

I

/

O

Module

Internal

Schematic

(

Figure

26

)

6.1

.

CURRENT

INPUT

CIRCUITRY

Since

there

are

four

identical

sets

of

circuitry

for

phase

A

,

B

,

C

,

and

ground

only

the

circuitry

for

phase

A

will

be

described

.

6.2

.

MICROPROCESSOR

SUPPORT

CIRCUITRY

Referring

to

the

Microprocessor

Module

Internal

Schematic

,

Figure

20

:

Referring

to

the

ct

Module

Internal

Schematic

,

Figure

The

microprocessor

is

supported

by

chip

selector

U

11

,

address

latch

U

5

,

32

K

bytes

of

EPROM

(

U

7

)

,

2

K

bytes

of

RAM

(

U

8

)

and

512

bytes

of

EEPROM

18

:

Current

is

input

to

the

relay

at

terminals

4

and

5

(

for

phase

A

)

,

stepped

down

by

current

transformer

T

1

and

full

wave

rectified

by

diode

bridge

BR

1

.

Resistors

R

1

and

R

10

convert

the

input

current

to

voltage

.

Diodes

D

1

,

D

5

and

CR

1

clamp

the

voltages

to

safe

values

.

Resistor

R

5

protects

the

microprocessor

input

(

U

2

,

on

Microprocessor

Schematic

,

Figure

20

)

.

For

low

level

current

inputs

,

up

to

3.75

Volts

across

resistor

R

1

,

the

input

voltage

is

measured

directly

by

the

analog

to

digital

(

A

/

D

)

converter

within

the

micro

-

computer

chip

(

U

2

,

Microprocessor

Module

Sche

-

matic

,

Figure

20

)

.

(

U

6

)

.

A

real

-

time

clock

chip

(

U

9

)

is

accessed

by

the

micro

-

processor

and

gives

date

and

time

information

.

For

relays

with

the

real

-

time

clock

option

,

a

lithium

battery

(

BT

1

)

type

BR

2016

or

CR

2016

is

in

a

battery

holder

on

this

board

.

Diode

D

3

and

resistor

R

44

are

in

series

with

the

battery

in

order

to

insure

that

the

battery

will

not

be

charged

.

Relays

without

the

real

-

time

clock

option

do

not

have

a

battery

.

Referring

to

the

Microprocessor

Module

Internal

Schematic

,

Figure

20

:

WARNING

Each

phase

and

ground

go

to

different

pins

on

the

microprocessor

U

2

and

are

multiplexed

internally

by

the

microprocessor

U

2

.

For

higher

level

signals

the

voltage

across

resistor

R

10

(

ct

Module

Internal

Sche

-

matic

Figure

18

)

is

scaled

by

a

ranging

chip

U

3

Replace

battery

with

ABB

Style

9648

a

03

h

01

only

.

Use

of

another

battery

may

present

the

risk

of

fire

or

explosion

.

10

Courtesy of NationalSwitchgear.com