Tektronix 067-0883-99 User manual

Tektronix,
Inc.
P.O.
Box
500
Beaverton,
Oregon
97077
061-2213-00
Product Group 45
COMMITTED
TO
EXCELLENCE
PLEASE CHECK FOR CHANGE INFORMATION
AT
THE REAR OF THIS MANUAL.
UNIVERSAL
LOAD UNIT
067
-0883-99
INSTRUCTION
MANUAL
Serial Number
_____
_
First Printing AUG 1979
Revised MAR 1982

The
Universal
Load
Unit
is
a
non-supported
Tektronix
product.
* * * * * * * * * *
Although thematerial inthismanual has been
thoroughly
edited and checked
for
accuracy, Tektronix, Inc., makes no
guarantees against typographical or human errors. Also, Tektronixassumes no responsibilityorliability, consequential
or
otherwise, of any kind arising from misinterpretation or misuse of the material in this manual. The contents of this manual
are subject
to
change
without
notice.
Copyright©
1979 by Tektronix, Inc., Beaverton, Oregon. Printed in the United States of America. All rights reserved.
U.S.A. and foreign TEKTRONIX products covered by U.S. and foreign patents and/or patents pending.
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

UNIVERSAL LOAD UNIT
LE
F CONTENTS
SECTION 1- GENERAL INFORMATION
Introduction
Description
Electrical Characteristics
Environmental Characteristics
Accessories
SECTION 2 - OPERATION
Front Panel Controls
Rear Panel Controls & Connectors
Initial Turn On
Operational Notes
WARNING I
THE FOLLOWING SERVICING INSTRUCTIONS ARE FOR USE BY
QUALIFIED PERSONNEL ONLY. TO AVOID PERSONAL INJURY, DO
NOT PERFORM ANY SERVICING OTHER THAN THAT CONTAINED IN
OPERATING INSTRUCTIONS UNLESS YOU ARE QUALIFIED TO DO SO.
SECTION 3 - THEORY OF OPERATION
Block Diagram Description
Circuit Description,
High Current Cells
Medium Current Cells
Low Current Cells
Digital Multimeter
Program Board
Power
Supplies
SECTION 4 - CALIBRATION TEST & PROCEDURE
Required Equipment List
Verification Procedure
Calibration Procedure
SECTION 5 - REPLACEABLE PARTS
SECTION 6 - DIAGRAMS & CIRCUIT BOARD ILLUSTRATIONS
APPENDIX A - PROGRAMMING PLUG-IN MODULE
Program Resistor Selection
Safe Operating Area Curves
Replaceable Parts List
Diagrams
i
1-1
1-1
1-1
1-3
1-5
1-5
2-1
2-1
2-4
2-7
2-7
3-1
3-1
3-4
3-4
3-4
3-5
3-5
3-8
3-8
4-1
4-1
4-2
4-4
A-1
A-2
A-10
A-13
A-18

2213-01
Universal Load Unit

UNIVERSAL LOAD UNIT
SECTION 1
GENERAL INFORMATION
Introduction
The Universal Load Unit (ULU) is a bench top testing device that will
provide a convenient method of performance checking the internal power
supplies in several Tektronix instruments. It may be used to test and
verify proper voltage regulation of single and multiple output supplies
under variable load conditions. The ULU is used in conjunction with
Programming plug-in modules that are temporarily installed, one at a time,
into the Load Unit through its front panel.
Description
The Universal Load Unit includes twelve active load cells (channels)
and one passive channel through which up to thirteen output voltage levels
can be concurrently loaded. The current through any active channel is
varied by an internal pulse generator to provide transient response testing.
The voltage or current in a selected channel may be displayed on the Load
Units front panel digital multi-meter. Also, each channel is monitored for
an out-of-tolerance condition.as indicated by one of thirteen comparator-
driven, front panel LED's. The thirteen position CHANNEL SELECTOR switch
is used to connect the ULU controls and output monitoring circuits to each
of the 12 active cells. As selected, each active load cell or channel can
be set up to provide a .resistive load or a constant current load for a
given power supply output. Each active load cell includes a current sensing
resistor, current amplifier and cell protection circuitry. Each programming/load
module supports 12 active and 1 passive channel. All twelve active channels
can be programmed by the installation of six user selected resistors per
channel (See Appendix A). The resistors select high or .low current levels
and equivalent load resistances and establish nominal voltages and tolerance
limits for the ULU's comparator circuitry. The passive channel (13) is
programmed with two fixed resistors.
·Each programming module is used to test the internal power supplies
in a specific Tektronix instrument and will be separately part numbered.
1-1

UNIVERSAL LOAD UNIT
1-2 @

UNIVERSAL
LOAD
UNIT
Electrical
Characteristics
Input
AC
Power
The
ULU
may
be
operated
at
115
or
230
VAC
(48
to
67
HZ)
and
requires
less
than
80
watts
during
normal
operation.
It
uses
a 1
amp
standard
3AG
fuse.
The
power
cord
is
detachable
and
will
plug
into
a female
receptacle
conforming
with
NEMA
#5-15.
(Two-pole,
three
wire
grounding).
Load
Cells
(Channels)
Maximum
and
minimum
input
voltages
and
currents
are
given
in
the
following
tabular
listing.
Current:
Max
Fused
Accuracy
Channels 1,
2,
7'
8 24.A
30A
±5%
± 0.5%
FS
Channels
3,4,9,10
10A
15A
±5%
±
0.
5%
FS
Channels
5,6,11,12
2A
5A
±5%±0.5%FS
Channel
13
1A
Voltage:
Max
Trip
Voltage
Saturation
Amps
(Crowbar)
(minimum)
Channels
1,2
50V
55V
S.2V
@
15A
max.
Channels
7,8
-50V -55V
S.2V
@
15A
max.
Channels
3,4
100V
11
ov
S.4.5V @
10A
max.
Channels
9'
10
-100V -110V S.4.5V @
10A
max.
Channels
5,6
160V 180V
S.8V
@
2A
max.
Channels
11
'12
-160V
180V
S.8V
@
2A
max.
Channels
13
350V
none
S.1V
@
1A
max.
Power
Maximum
•
Channels
1,2,7,8
120W
Channels
3,4,9,
10
80W
Channels
5,6,11,12
80W
Channel
13
10W
*
500
watts
total
input
power,
all
channels.
or
1-3

UNIVERSAL
LOAD
UNIT
1-4

UNIVERSAL
LOAD
UNIT
Operational
Modes:
The
ULU
includes
two
operational
modes;
Chop
individual
and
Chop
All.
Chop
Rate:
Chop
Duty
Cycle:
Chop
Rise/Fall
time:
96
Hz
nominal
50%
nominal
_5-
10
µS
(10%-90%)
Indicators:
The
ULU
includes
two
indicating
devices
-a
digital
multimeter
(DMM)
display
and
10
Out-of-Regulation
LED's.
DMM
Ranges:
DMM
Accuracy:
LED
Accuracy:
Voltage
2v,2ov,2oov,2ooov
±0.1% ± 2
counts
Current
200A,20A,
2A
1%
± 6
counts
±5%
deviation
from programmed
value
Environmental
Characteristics
The
ULU
has
been
tested
and
verified
operable
in
the
following·
class
5
categories:
shake,
shock,
transportation,
bench
handling
and
abbreviated
thermal
tests
(limited
to
o
0
c
to
50°c
with
instrument
on).
Accessories
Standard.
Accessories
for
the
ULU
include
this
manual
(061-2213-00)
and
the
following
listed
items:
Mating
Connectors
P1
&
P2
(2)
Mating
Connector,
P3
AC
Power Cord
Packing
Box
Foam
Pad
Pad
Set
131-0097-00
131-0293-00
161-0066-00
004-0766-00
004-0281-00
004-1092-00
Optional.
Optional
Accessories
for
the
ULU
include
the
following
listed
items:
@
Unprogrammed
Plug-in
&
Connector
Set
7612D
Programming
Plug-in
7612D
Programming
Plug-in
Inst.
Manual
7912AD
Programming
Plug-in
7912AD
Programming
Plug-in
Inst.
Manual
1-5
067-0919-99
067-0921-99
061-2214-00
067-0920-99
061-2213-00