Sencore SCR250 User guide
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SM
View
Instra
SCR250
SCR
&
TRIAC
TEST
ACCESSORY
Schematic and Parts List
3200 Sencore Drive,
Sioux
Falls, South Dakota 57107
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SCR250
SCR
&
TRIAC
TEST
ACCESSORY
.-
Operation and Application
Manual
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SCR
250
SEN
CORE
3200
Sen
core Drive,
Sioux
Falls, South Dakota57107
1
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TABLE
OF
CONTENTS
SAFETY PRECAUTIONS
•.....•.....•............•
Inside
Front
Cover
DESCRIPTION
Introduction
........
.
...
.
...................................
3
Specifications
.....................................
.
........
3
Controls
....................................................
5
OPERATION
Introduction
.........
.
.......................................
6
Battery Installation/Replacement
.............................
6
BatteryTest
.........................................
.
...
.
...
7
Mounting
The SCR250 On The
"Z
METER"
..........
.......
....
7
Connecting
The SCR250 To The
"Z
METER"
....
...
......
......
9
Testing SCRs
.........
.....
....
...
........
..
........
........
10
Testing TRIACs
.........
........
......
....
..
...
.....
.
.......
11
APPLICATION SECTION
SCR
Operation
.............................................
12
SCR
Types.
.. .. . .. ... .. .. .. . .. .. . ... .. . .... . . .. .. . ... .. . . . . 13
TRIAC Operation
...........................................
14
Testing SCRs And TRIACs For Leakage
......................
15
Determining Operating Voltage Of An SCR Or TRIAC
..
.......
. 15
SERVICE AND WARRANTY INFORMATION
.•.....••.
Inside
Back Cover
2
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DESCRIPTION
Introduction
The
SCR250
SCR
&
TRIAC
Test
Accessory is designed
to
be used
with
any
Sencore Z-Meter to simplify SCR and
TRIAC
testing. The
SCR250 dynamically
tests
both
sensitive
gate
and
normal
gate
SCRs
for
turn
on and leakage under normal operating voltage conditions.
The
SCR250 also dynamically
tests
TRIACS for leakage
and
proper
turn
on
in
both
the forward
and
reverse direction
at
normal operating
voltage
levels.
Specifications
SCR
Tests
(Out-of-Circuit)
Dynamic
test
of
SCRs for
"turn
on"
and
for leakage. Maximum
test
voltage
equals
the
maximum
leakage voltage range
of
the
Z-Meter
used,
not
to exceed 1000volts.
SENSITIVE
GATE TEST: Maximum
gate
current
of 2.6 rna applied
to
the
gate
leadwhen
GATE
CURRENT
button
is depressed.
NORMAL
GATE
TEST:
Maximum
gate
current
of 62 rna applied
to
the
gate
lead when
GATE
CURRENT
button
isdepressed.
TRIAC
Tests
(Out-of-Circuit)
Dynamic
test
of
TRIAC
for
"turn
on"
and
leakagein
both
the
forward
and
reverse direction. Maximum
test
voltage equals
the
leakage
voltage
range
of
the
Z-Meter used,
not
to
exceed 1000 volts.
POSITIVE
GATE
BIAS
TEST: Maximum
gate
current
of 62 rna
applied
to
gate
lead when
GATE
CURRENT
button
is
depressed.
NEGATIVE
GATE
BIAS
TEST: Maximum
gate
current
of
62 rna
applied
to
gate
lead when
GATE
CURRENT
button
depressed.
Gate
voltage
negative with respect to
MTl
lead. MT2 lead negative with
respect
to
MTllead.
General
TEMPERATURE
RANGE
(Typical): 32-130 degrees F.
POWER
REQUIREMENTS:
Three
AA
batteries
required
(not
included). BATTERY OK
LED
will light
if
combined
battery
voltage
drops
below
3.5
volts.
SIZE:
1.8"
X 6.2" X
6.5"
HWD.
WEIGHT:
1.2 pounds
with
batteries.
3
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TEST
LEADS
(supplied): one multiconductor
test
cable with color
coded
and
labeled E-Z Hook® connectors for ease of connection
to
the
SCRor
TRIAC
under
test.
I
i
SCR
&
TRIAC
TO BE USED
Wll
H ANY S
(N
COAE l - M( l
ER
CO
NNECT TO
SC
R
O~
HUAC
The front
panel
controls. (NOTE: Use
the
39G196 TEST LEADS
supplied
with
this
unit
only.)
E-Z Hook Is a registered trademark of
E-Z
Hook.
Di
vision
of
Tektest, Inc.
4
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Controls
1.
BATT
OK
LED-Lights
if
the
battery
voltage is sufficient for
ope
ration
when
the
PUSH
FOR
BATT
TEST
button
is
pressed
.
2.
PUSH
FOR
BATT
TEST
BUTTON-Use
with
BATT
OK
LED
to
determine
battery
condition.
3.
SENSITIVE
GATE
SCR
BUTTON-Provides
a low level
gate
current
when GATE
CURRENT
button
is in
the
"ON"
position for
testing
sensitive
gate
type
SCRs.
4.
NORMAL
GATE
SCR
BUTTON-Provides
a normal level
gate
current
when
GATE
CURRENT
button
is
in
"ON"
position
for
testing
normal
gate
type
SCRs.
5.
POSITIVE
GATE
BIAS
TRIAC
BUTTON-
Provides a positive
gate
voltage
when
GATE
CURRENT
button
is in
the
"ON"
position.
6.
NEGATIVE
GATE
BIAS
TRIAC
BUTTON-Provides a negative
gate
voltage
when
GATE
CURRENT
BUTTON
is
in
the
"ON"
position.
Reverses
the
polarity of
the
MTl
and
MT2
TRIAC
leads for
checking
the
operation
of
the
TRIAC
in
the
"reverse
"
current
direction.
7.
GATE
CURRENT
BUTTON
-Applies
gate
current
to
component
under
test.
8.
TEST
LEAD
JACK-Supplies
test
voltages to component under
test.
5
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OPERATION
Introduction
The
SCR250 connects
to
any
Sencore Z-Meter to analyze SCRs
and
TRIACs
for
proper
turn
on
and
for excessive leakage current.
The
leakage
voltage
supply
of
the
Z-Meter supplies
the
test
voltage
to
dynamically
test
the
SCR
or
TRIAC
under
normal
operating
voltage
conditions.
The
Z-Meter's digital
leakage
current
display
shows
the
results
of
these
tests.
The
SCR250 selects
the
desired
test
and supplies
the
gate
current
needed
to
turn
the
SCR
or
TRIAC
on. The SCR250
can
be
easily
operated
using
the
information
on
the
front panel.
Simplified
operating
instructions
are
included
on
the
top of
the
SCR250 for quickreference.
Battery
Installation/Replacement
The SCR250 requires 3
''
AA''
batteries
for operation. Three alkaline
batteries
typically give
up
to
3600
tests
before
they
need
to
be
replaced.
Toinstall
or
replace
batteries:
l.Remove
the
two
screws securing
the
battery
compartment
cover
on
the
rear
of
the
SCR250.
2.Pull
the
battery
holder
out
of
the
battery
compartment
using
the
pull
tab
.
3.Install3
"AA"
batteries,
matching
the
polarity
of
the
batteries
and
the
polarity
indicators
on
the
battery
compartment
as
shown
in
Figure
1.
4.Slide
the
battery
holder
back
into
the
battery
compartment.
5.Secure
the
battery
compartment
cover
with
the
two
screws.
6
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.....
'1
...
..
Fig.
1:
Installing batteries.
Battery
Test
The
condition
of
the
batteries
is
easily
tested
using
the
PUSH
FOR
BATT
TEST
button
on the front of
the
SCR250. When
the
PUSH
FOR
BATT
TEST
button
ispressed, a
BATT
OK
LED
will
light
if
the
batteries
are good.
To
test
battery
condition:
l.Press
the
PUSH
FOR
BATT
TEST
button
on
the
front
of
the
SCR250.
2.0bserve
the
BATT
OK
LED.
If
the
BATT
OK
LED
does
not
come
on, replace
the
batteries following
the
procedures given in
the
previous
section
on
''Battery
Installation/Replacement''.
Mounting
The
SCR250
On
The
"Z
METER"
The
SCR250 can be placed in a convenient location beside
the
Z·Meter
or
it
can
be secured
to
the
top of
the
Z.Meter for portableuse.
The
SCR250 can be secured
to
the
Z.Meter using
the
Velcro®
strips
supplied
with
the
SCR250. The SCR250 comes with two Velcro®
strips
called the "hooks"
and
two
strips
called
the
"loops".
The
strips
called
the
"hooks" feel rough
to
the
touch
due to
the
many
rows of
nylon
"hooks
". The
strips
called "loops" feel much softer
to
the
touch.
Ve
lc
ro is a
re
gistered t•ademark of V
elcro
USA,Inc. 7
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To
attach
the
SCR250
to
a Z-Meter:
1. Clean
the
top
of
the
Z-Meter
and
the
bottom
of
the
SCR250
with
a
good household cleaner
to
ensure
proper
adhesion
of
the Velcro®
strips
to
the
case.
2.
Remove
the
protectivebackingfrom one ofthe
''loop''
type
Velcro®
strips
and
mount
the
strip
immediately behind
the
warning label
on
the
top
of
the
Z-Meter,
as
shown in
Figure
2.
Fig.
2:
Velcro® strips installed
on
the top
of
a "ZMETER".
3.
Mount
the
other
"loop"
type
Velcro®
strip
on
the
top
of
the
Z-
Meter two inches behind thepreviously installed Velcro® strip.
4.
Place
the
SCR250 on
top
of
the
Z-Meter in
the
location desired.
Determine where
the
Velcro®
strips
need
to
be placed on the
bottom
of
the
SCR250
in
order to
mate
with
the
Velcro®
strips
installed
on
the
Z-Meter.
5.
Mount
the
two
"hook"
type
Velcro®
strips
to
the
bottom of
the
SCR250 so
they
will
mate
with the two "loop"
type
Velcro®
strips
mounted on
the
Z-Meter.
6.
Place
the
SCR250 on
top
of
the
Z-Meter
and
press
down firmly
to
mate
the
Velcro® strips. The SCR250 is now securely fastened
to
the
Z-Meter
as
shown
in
Figure
3.
Velcro Is a registered trademark
of
Velcro USA, Inc. 8
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SCR
&
TRIAC
TEST
ACCI!SSORV
o,jATI
"IS'
oii!RlNl
tlAJ)
Fig.
3:
SCR250 mountedon top
of
a
"Z
METER".
To
remove
the
SCR250 from
the
Z·Meter (to replace
the
batteries, for
example), simply pull
up
on one corner of
the
SCR250. The Velcro®
strips
will release their hold
and
the
SCR250 can be removed.
ConnectingThe SCR250
To
The
''Z
METER''
The
SCR250 is electrically connected to
the
Z·Meter
through
a cable
coming
out
the
back
of
the
SCR250. A 39G196
TEST
LEAD
cable
is
also
supplied with
the
SCR250
to
connect
to
the
SCR or
TRIAC
under
test.
NOTE:Use
the 39G196
test
lead cable
that
is supplied
with
the
SCR250.
Do
not
use
any
other
type
of
test
lead
with
this
instrument.
The
three
E-Z
Hook
® connectors are color-coded for lead identification
and
are
marked
with
the
component
leads
they
are to be connected
to.
To
connect
the SCR250
to
the
Z·Meter:
!.Connect
the
cable from
the
back of
the
SCR250
to
the
BNC
TEST
LEAD
jack
on
the
front
of
the
Z-Meter.
2.Connect
the
39G196
TEST
LEAD
to
the
TEST
LEAD
jack
on
the
front
of
the
SCR250.
Velcro
is
aregistered trademark
ol
Velcro
USA,
Inc.
E-Z
Hook
is a registered trademark
of
E·ZHook, Division
of
Tektest, Inc.
9
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Testing
SCRs
The following procedure checks
an
SCRfor
"turn-on"
and
leakage. The
SCR
must
pass
both
checksbefore
it
is considered good.
To
test
an
SCRwith
the
SCR250:
l.Connect
the
SCR250
test
leads
to
the
SCR
as
follows:
a. Connect
the
Blue E-Z Hook®
to
the
SCR
gate
lead.
b. Connect
the
Black E-Z Hook®
to
the
SCR cathodelead.
c.
Connect
the
Red E-Z Hook®
to
the
SCR anode lead.
r--------
WARNING----------.
Be sure
the
test
leads from
the
SCR250 are connected to
the
corresponding
leads on
the
device
under
test. Incorrect lead
connection can damage
the
device undertest.
2.
Press the
SENSITIVE
GATE
button
or
the
NORMAL
GATE
BUTTON dependingon
the
type
ofSCRbeingtested.
NOTE:
If
the
SCR
type
is unknown, press the
SENSITIVE
GATE
button
first. This supplies a lower current to check
sensitive
gate
SCRs
for proper tum-on.
If
the
unknown
SCR
does
not
pass
the
"tum-on"
test
in
step
4, press the
NORMAL
GATE
button
and
repeat step
4b.
3.
Set
the
APPLIED
VOLTAGE or
LEAKAGE
VOLTAGE switch
on
the
Z-Meter
to
the
rated
working voltage of the SCR under test.
If
the
rated
voltage is
not
known, refer
to
the
section on "Determining
the
Operating Voltage of
an
SCR
or
TRIAC"
found
in
the
Applications
sectionof
this
manual.
4.Perform
the
"turn-on" test:
a. Depress
the
GATE
CURRENT
button
to the
''ON''
position.
b.
Press
the Z-Meter
LEAKAGE
button
.The display on the
Z-
Meter
will overrange withflashing "888" for a good SCRindicating
that
the
device is
"turned
on"
and
current is flowing through it.
5.
Perform
the
"leakage" test:
a.
Set
the
GATE
CURRENT
button
to
the
"OFF"
position.
b.
Press
the Z-Meter
LEAKAGE
button. Thedisplay on
the
Z-
Meter
will show no leakagefor a good device.
E·Z
Hook
Is
a registered trademark
of
E·Z Hook, Division
of
Tektest, Inc.
10
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Testing
TRIACs
The
following procedure checks a
TRIAC
for "turn-on" and leakage in
both
the
"forward"
and
the
"reverse"
direction. The
TRIAC
must
pass
all
tests
before
it
is consideredgood.
To
Test
a TRIAC
with
the
SCR250:
1.Connect
the
SCR250
TEST
LEAD
to
the
TRIAC
as
follows:
a. Connect the Blue E-Z Hook®
to
the
gate
lead
of
the
TRIAC.
b. Connectthe BlackE-Z Hook®
to
the
MTllead
of
the
TRIAC.
c.
Connectthe Red E-Z Hook® to
the
MT2lead
ofthe
TRIAC
.
......---------WARNING-----------.
Be
sure
the test leads from
the
SCR250 are connected
to
the
corresponding
leads on
the
device
under
test. Incorrect lead
connection
can
damage
the
device under test.
2.
Press
the
POSITIVE
GATE
BIAS
button
on
the
SCR250.
3.
Set
the
APPLIED
VOLTAGE or
LEAKAGE
VOLTAGE switchon
the
Z-Meter
to
the
rated
working voltage of
the
TRIAC under
test.
If
the
rated
voltage
is
not
known, see
the
section on "Determining
the
Operating
Voltage
of
an
SCR
or
TRIAC"
found in
the
Applications
section
of
this
manual.
4.
Perform
the
"turn-on"
test:
a.
Depress
the
GATE
CURRENT
button
to
the
"ON"
position.
b.
Press
the Z-Meter
LEAKAGE
button. The display on
the
Z-
Meter
will
overrange
with
flashing
"888"
for a good
TRIAC
indicating
that
the
device is
"turned
on"
and
isconducting.
c.
Press
the
NEGATIVE
GATE
BIAS
buttonandrepeatstep
4b.
5.
Perform
the
''leakage''
test.
a.
Set
the
GATE
CURRENT
button
to
the
"OFF"
position.
b.
Press
the Z-Meter
LEAKAGE
button.
The display
on
the
Z·
Meter
will show no leakage for a gooddevice.
c.
Press
the
POSITIVE
GATE
BIAS
button
and
repeat
step
5b.
E·Z
Hook
Is aregistered trademarkof
E·Z
Hook, Division
of
Tektest, Inc.
11
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APPLICATION
SECTION
SCR
Operation
A Silicon Controlled Rectifier (SCR) is a three lead device
that
functions like a
DC
switch when given
the
proper control signal.
An
SCR has a cathodelead
and
an
anode lead
just
like a
standard
rectifier.
A
third
lead, called
the
gate
lead, controls
the
operation
of
the
SCR.
An
SCR functions like
an
open circuitwhen
it
is
"turned
off" and like a
diode when
the
SCR is
"turned
on". This SCR action is controlled
by
the
signal applied to
the
gate
lead. Figure 4 shows
the
symbol used on
schematics for
an
SCR. Notice
that
the
symbol looks similarto a diode
with
the
exceptionof
the
gate
lead.
Red
Test
Clip
Anode
SCR
Blue Test
Clip
Black Test
Clip
Cathode
Fig. 4: Schematic symbol
of
an
SCR
with SCR250
test
leadconnections.
With
no
gate
current applied
to
the
gate
lead,
the
SCR acts like a
switch
that
is
in
the off position. One common failure of SCRs is
the
inability
to
completely
shut
off.
The
SCR
may
be either totally
shorted
or
leaky. Some defective SCRs become leaky only when the voltage
applied between
the
anode
and
the
cathode is near
the
peak operating
voltage
and
thus
they
must
be
tested
at
theiroperatingvoltage.
SCRs
"turn
on"
when a small
current
is applied
to
their
gate
lead. A
"turned
on"
SCR
acts
just
like a diode, allowing
current
to
flow
in
the
forward direction only.
In
the
reverse direction, no current flows.
Anothercommonfailure
in
SCRs
is
a failure
to
'
'tum
on.''
12
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SCRTypes
SCRs
come
in
a variety of sizes, shapes,
current
ratings,
and
voltage
ratings.
They can, however, all be classified into one of
two
types:
Sensitive
Gate
and Normal Gate. Sensitive
Gate
SCRs
get
their
name
from
the
fact that
they
are
very sensitive
to
the
current
applied
to
the
gate
lead. They are typically used
in
low
current
applications where
only
a small gate control current is available. Sensitive
Gate
SCRs
come
in
a variety
of
physical shapes
and
sizes and
can
not
be easily
distinguished
by simplylooking
at
them.
For
many
applications, Sensitive
Gate
SCRs, are too sensitive for
reliable use. Internal
currents
in
the
SCR, or small
currents
in
the
triggering
circuits,
may
accidentally cause these SCRs
to
"turn
on."
Heat
can
also cause internal leakage
currents
to rise
to
the
point
of
"turning-on"
the SCR.
To
prevent
SCRs from accidentally
"turning-on",
many of
them
have
an
internal bleeder resistance built
into
them.
This bleeder resistance is placed between
the
gate
and
cathode
lead
as
shown
in
figure
5.
The resistance bleeds off any
internal
currents
that
might
build
up
and
prevents
the
SCR from
accidentally
"turning
on"
by
itself. Due
to
the
internal resistance,
these
SCRs require a higher external
gate
current
to
turn
them
on.
In
most
applications, this additional
gate
current
is easily obtainable,
thus
these
SCRs have become more popular
than
the
sensitive
gate
type
and
are called •'normal
or
standard
gate
SCRs.''
Anode(A)
Gate(G)
Cathode(K)
Fig.
5:
Equivalent
circuit
of
a normal gate
SCR.
13
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TRIAC
Operation
A TRIAC is a bidirectional device similar in operation
to
an
SCR
except
that
it
passes current
in
both
directions when
"turned
on.''
Figure 6 shows
the
schematic symbol for a TRIAC. Note
that
the
symbolresembles
two
diodes facing opposite directions. A TRIAC
has
three leads labeled: GATE,
MTl
and
MT2. The
gate
lead performs
the
same function
as
the
gate
lead on
an
SCR:
it
turns
the
device on.
The
other two leads
are
labeled differently from an SCR because
the
function of these leads change
with
the
polarity
of
the
voltage applied
to the leads. The
TRIAC
lead electrically closest
to
the
gate lead
is
simply called
the
Main Terminal 1 (MTl) lead,
and
the
other lead
is
called
the
MainTerminal 2 (MT2) lead.
Red Test
Clip
Terminal2
(MT2)
TRIAC
Blue
Test
Clip
Black Test
Clip
Fig.
6:
Schematic
symbol
of
a TRIAC
with
SCR250 test
lead
connections.
TRIAC failures are much
the
same as SCR failures.
One
common
failure mode
in
a
TRIAC
is
an
open.
In
other
words,
the
TRIAC can
not
be
"turned
on."
A defective
TRIAC
can fail
to
pass
current
on
one
direction
but
properly
pass
it
in
the
otherdirection. The reason for
this
is
that
a
TRIAC
functionally looks like two SCRs facing in opposite
directions. A defective TRIAC can fail
to
pass
a current
in
one
direction only
as
would be the case if one of
the
two antiparallel SCRs,
in
the SCR analogy, were
to
fail,
or
it
can fail
to
pass
current
in
both
directions.
Like SCRs,
TRIACs
can
become leaky. A defective TRIAC can
leak
in
one direction only
or
in
both
directions. Some
TRIACs
become
"leaky"
only when
the
full
working voltageis applied
to
them.
14
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Testing
SCRs
And
TRIACs
For
Leakage
The
leakage test for SCRs
and
TRIACs
is done automatically when
the
GATE
CURRENT switch on
the
SCR250
is
in
the
"OFF"
position.
Any
reading displayed
on
the
Z-Meter while
the
LEAKAGE
button
is depressed is
the
leakage of
the
component
under
test.
The
leakage
test
is performed
at
the
rated
voltage of
the
device
and
gives a
true
indication
of
the
leakageunder normal operatingvoltages.
If
you
need a more criticalleakage reading for SCRs, such
as
for those
used
in
the
high voltage shutdown circuits
of
TVs, place
the
LEAKAGE
RANGE switch
to
the
100uA range.
With
the
LEAKAGE
RANGE switchin
this
position, leakage
currents
down
to
1 microamp
will
be measured.
The
leakage
in
SCRs
and
TRIACs
should
not
exceed 10
uA
at
room temperature.
TRIACs
will normally
show
slightly differentleakage currentsineachdirection.
Some
defective
SCRs
and
TRIACs
become leaky only when
they
become
warm.
If
the
SCR or
TRIAC
is suspected of being
"thermal",
in
other
words
it
drastically changes characteristics when
it
becomes
warm,
heat
the component
with
a
heat
gun.
A
"thermal"
SCR or
TRIAC
will show a rapidincrease
in
leakage
as
it
becomes warmer.
Determining
Operating
Voltage
Of
An
SCR
Or
TRIAC
SCRs
and
TRIACs typically do
not
have their working voltage
stamped
on the case
as
do capacitors. Furthermore, their working
voltage
is generally
not
listed in
the
parts
list
of
the
instrument.
The
working
voltage
can
often be determined
by
one of
the
following
methods.
A
good
indication of
the
rated
voltage of
the
SCR
or
TRIAC
can
be
obtained
by
looking
at
the
operating voltage of
the
circuit
that
the
device
is
used
in. For example, if
the
SCR
or
TRIAC
is used
to
switch
AC
line
power,
the
device
must
be able to
withstand
the
full
peak-to-peak voltage of
the
line. This requires a device having a
rated
working
voltage
of
at
least
400 volts.
An
SCR used in
the
regulator
section
in a television horizontal
output
section
must
have a
rating
of
at
least
400 to 500 volts to
withstand
the
reverse voltage from
the
flyback. SmallSCRs
used
in hold down circuits, for example, typically
operate
from a 24 volt B +supply
and
usually have a working voltage
rating
of 50 volts
or
more.
The
best
way to determine
the
operating voltage
of
an
SCR
or
TRIAC
is
to
cross
the
device over
to
a
substitute
type
using a
substitution
guide
for semiconductors. The working voltage of
the
substitute
SCR
or
TRIAC
is
equal to or higher
than
the
working voltage of
the
device
you
are
testing.
15
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There are occasions when
the
SCR
or
TRIAC
to
be
tested
is
not
listed
in a
substitution
guide
and
no circuit voltages are available.
With
the
following procedure, you
can
test
the
SCR or
TRIAC
at
a
potential
below
that
of
its
rated
voltage without fear of
damaging
the device
from applying too muchvoltage.
To
test
an
SCR
or
TRIAC
at
a
potential
below
its
rated
voltage:
a. Set the
APPLIED
VOLTAGE switch on
the
Z-Meter to the
25
volt range. This is
the
lowest
standard
voltage
range
for SCRs
and
TRIACs.
b.
Test
the SCR or
TRIAC
following
the
procedures given in
the
sections on
"Testing
SCRs"
or
on
"Testing
TRIACs".
c.
If
the
device does
not
test
good when
the
"turn-on"
test
is
performed,
increase
the
applied
voltage
to
the
next
standard
voltage range.
Standard
working voltages for SCRs and
TRIACs
are 25, 50, 100, 200,
...
, 1000 volts in 100 volt increments.
16
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3J.V9
300HJ.V.J
300NV
+
~
ro
et::tD
l'l
It
lJ
(I)
...
(\J
~i\J
It
~~
lJ
:.:
Nl{)
Cl::
.-'
0 0 0
'-~-=---
.--
-,
'-
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SCHEMATIC
REFERENCE
R1
R2
R3
CR1
CR2,3
NOTES:
PART
NUMBER
14C1-680
14C1
-152
14C11-183
16G18
50C5-2:A
25G379
20G21
26G124
25A377
25A378
39G196
68A14-8
68A14-11
68A14-12
1_
All
resistances in
ohms_
2 . Board interconnection
no
t
es
:
D denotes a single push-
on
type connector_
Qden
otes wire soldered to
PC
board.
DESCRIPTION
Resistor, carbon,68 OHM,1/4W
Resistor, carbon,1.5K,1
/4W,5%
Resistor, carbon,18K,2W,10%
Diode, Silicon, 1.0 Amp
Diode, 1N4148
Switch, momentary-push
LED,Indicator with resistor
Connector,BNC
Switch,pushbutton-4 station
Switch, pushbutton-push-on/off
Complete Test Lead
E-Z
Hook test clip, red
E-Z
Hook test clip, black
E-Z Hook test clip, blue
odenot
es
mol
ex
connec
ti
on
. Numbers inside
or
along side i
nd
icate
the pin number of the
pl
ug
-i
n connector.
3 . All
co
ntrols,jac
ks,
and displays
on
exterior of unit are shown
wi
th box around the name.
E·Z
Hook Is aregistered trademarkol
E-Z
Hook, Division
ol
Tektest, Inc.
SEN
CORE
3200 Sencore Drive, Sioux Falls, South Dakota
57107
Form
3508
Printed
in
U.S.A.
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