Tektronix TEKTOOLS DMM155 User manual

Tektronix
/
0
U
0
0
O
0 0
O 00
O
000
O 00
O
000
O 00
O 000
O 00
O
000
O 00
O 000
O 00
O
000
O 00
O
000
O 00
O
000
O 00
O 000
O 00
O 000
O 00
O
000
O 00
O 000
O 00
O 000
O 00
O 000
O 00
O
000
O 00
O
000
O 00
O 000
O 00
O
000
O 00
O 00 0
DMM155 & DMM157
Digital Multimeters
Instructions
070-8943-02

Tektronix
/
DMM155 & DMM157
Digital Multimeters
Instructions
070-8943-02

Table of Contents
Product Description
1
Controls and Connectors
2
Using the Multimeter
4
Preparing for Measurement
4
Measuring Voltage
4
Measuring Resistance
5
Checking Continuity
6
Testing Diodes
6
Measuring Capacitance (DMM157)
6
Measuring Current
7
Holding a Measurement
7
Offsetting a Measurement
7
Extending the Display Resolution
8
Selecting a Range
8
Resetting the Display
8
Using the Tilt Stand and Holster Hook
9
Using the Probe Holders
10
Replacing the Battery
11
Replacing the Fuses
13
Replacement Parts
15
Specifications
16
General Characteristics
16
Measurement Ranges and Accuracies
17
Copyright Tektronix, Inc. 1993. All rights reserved.
Tektronix products are covered by U.S. and foreign
patents, issued and pending. Information in this
publication supercedes that in all previously published
material. Specifications and price change privileges
reserved.
Tektronix, Inc., PO. Box 1000, Wilsonville, OR
97070-1000
TEKTRONIX and TEK are registered trademarks Of
Tektronix, Inc.

Safety
This manual contains information and warnings that must
be followed for operating the Instrument safely and
maintaining the product in a safe operating condition.
A CAUTION. Caution statements identify conditions or
LIApractices
that could result in damage to the
equipment or other property.
A WARNING. Warning statements identify conditions
La or practices that could result in personal injury or
loss of life.
Terms as Marked on Equipment
A
ATTENTION
Refer to manual
Do Not Operate Without Covers — To avoid personal
injury, do not apply any voltage or current to the product
without the covers in place.
Electric Overload — Never apply a voltage to a connec-
tor on the product that is outside the range specified for
that connector.
Do Not Immerse — The product is not waterproof.
Product Description
The DMM155 and DMM157 are rugged, handheld digital
multimeters that allow you to make accurate measure-
ments quickly and easily. Whether you are a professional
or hobbyist, these instruments provide a useful range of
features:
•
Shock-absorbing cover
• Tilt stand, holster hook, and probe holders
•
33 digit (2000 count) LCD display
• Auto range (volts, ohms) and manual selection
• Measurement hold or offset
• Measures DC and AC voltages, DC and AC current,
resistance, diode voltage, continuity, and capacitance
(DMM157)
• Overvoltage and overload protection
• Low-power ohms setting
•
Diode and continuity tester with audible signal
•
Alarm that warns of improper connections to the
current inputs
•
Recessed input jacks for safety
•
Automatic power off after 30 minutes prolongs battery
life
• Low-battery indicator
•
Uses standard 9 V battery
•
Double Insulated
II
1

omo
ir rp,i
3,u
10
9
8
7
10A mA COM V11-01-
©
Tektronix
Figure 1: Controls and Connectors
6 3
Controls and Connectors
See Figure 1 for location of controls and connectors.
1. HOLD —
Holds or "freezes" the measurement
display.
2. OFFSET --
Offsets the Measurement. This subtracts
the last two digits from subsequent measurements.
3. Vf1-01- (or VO -
4 1- ) — Input for measuring volts,
ohms, diodes, and continuity. (The DMM157 also
measures capacitance.)
4. COM — Input for the common (ground reference)
connection.
5. mA —
Input for measuring current up to 200 mA.
6. 10A —
Input for measuring current above 200 mA.
7. Rotary Switch —
Selects the multimeter function:
volts, ohms, diodes, continuity, or amperes. (The
DMM157 also measures capacitance.)
8. AC/DC, D/LPfl — Selects AC or DC voltage, AC or
DC current, high- or low-power ohms.
9.
RANGE, RESET — Press this button to select one
measurement range. Hold it down for 2 seconds to
return to auto range. This control will also restore the
display after automatic power off.
10. Digital
Display —
This liquid crystal display (LCD)
has a maximum reading of 1999
(33.
digit). The
display indicates auto range, auto polarity, decimal
point, overrange, AC (DC implied), 0/LPO,
measurement units, hold, and offset.
2
3

Using the Multimeter
Please read this section to learn how to use your
DMM155 or DMM157 Digital Multimeter safely and
efficiently.
Preparing for Measurement
1.
Wait 30 seconds after turning on the meter before
making a measurement.
2.
Set the rotary switch to the function you want to use
before connecting the probes to voltage or current.
Disconnect the test leads from the voltage or current
before selecting a new function.
3. Disconnect power to the equipment under test if you
are measuring resistance or capacitance, testing
continuity, or checking diodes.
4. If you use the multimeter near equipment that
generates electromagnetic interference, the display
may be unstable or indicate incorrect measurement
values.
Measuring Voltage
A WARNING.
Do not apply more than 600 VDC or 600
LAVAC R
ms to the input. Do not apply more than
600 VDC or 600 VAC R ms between the COM input
terminal and earth ground. Exceeding these limits
creates a shock hazard to the user and can also
damage the meter.
Use extreme caution to avoid personal contact with
high voltage when measuring in high voltage circuits.
1. Connect the black test lead to the COM (—) terminal
and the red test lead to the
VD (+) terminal.
4
2 Set the rotary switch to the
V function.
3 Press the AC/DC button to select AC or DC
measurement. (The display indicates AC but not DC.)
4 Connect the test leads across the source or load. The
multimeter automatically selects the range and
displays the polarity and voltage. Input voltage that
exceeds the selected range causes the
most-significant digit ("1" or '-1") to flash.
Measuring Resistance
I. Connect the black test lead to the COM terminal and
the red test lead to the vn terminal.
2. Set the rotary switch to the Q position to measure
resistance up to 2 MO; set it to the 2-20 MD position
to measure resistance from 2 MO to 20 MO.
A WARNING. To prevent possible personal injury or
Udamage to the meter, make sure the device being
tested is off and no source of voltage is present.
3. To measure in-circuit resistance shunted by
semiconductor junctions, press the
D/LPD switch for
lower power resistance measurements. The display
indicates "LPO".
4. Connect the test leads across the resistance. For the •
best accuracy when measuring low resistance, short
the test leads together and press
RANGE: then press
the
OFFSET button. This selects the lowest range and
compensates it for the resistance of the test leads.
5

Checking Continuity
1. Connect the black test lead to the COM terminal and
the red test lead to the Vfl terminal.
2. Set the rotary switch to the ))-614- position.
3. Connect the test leads adross the resistance. The
beeper sounds if the measurement is lower than 25
and continues to sound until the resistance increases
to greater than 200 O.
Testing Diodes
1 Set the rotary switch to ))-ot- position.
NOTE. Do not use AC volts for testing diodes.
2 Connect the black test lead to the COM (—) terminal
and the red test lead to the vn (+) terminal.
3. Connect the test leads across the diode to check.
Normally, the forward voltage drop of good silicon
diodes is between 0.400 V and 0.900 V. If the diode
under test is defective, "000" (short circuit) or
approximately 2.6 V (non-conducting) is displayed.
4. Reverse Bias Check. The display reads
approximately 2.6 V with the diode reverse biased.
The multimeter displays "000" or some other value
lower than 2.6 V if the diode is shorted (or 'resistive).
Measuring Capacitance (DMM157)
1. Connect the black test lead to the COM terminal and
the red test lead to the V0 - 11 - terminal.
2. Set the rotary switch to the range needed
(2pF-200 pF) for the capacitance to be measured.
3.
Measure capacitance by placing the test leads across
the component. Observe polarity markings (if any) on
6
the capacitor by placing the red lead on the (+) and
the black lead on the (—) component leads.
Measuring Current
1. Connect the black test lead to the COM terminal and
the red test lead to the mA terminal for a maximum of
200 mA. For a maximum of 10 A, move the red test
lead to the 10 A
terminal. (The multimeter will indicate
to a maximum of 13 A, but the maximum measuring
time at that current level is 30 seconds.)
2. Set the rotary switch to the range needed
(2 mA-10 A)
for the current to be measured. Select
AC or DC current measurement using the
AC/DC
switch.
NOTE.
If you do not know the correct current range,
start at the highest range and work down.
3. Connect the test leads in series with the load under
measurement.
Holding a Measurement
To retain a measurement, press the
HOLD button. The
hold indicator (H)
appears on the display and the reading
will not change. Press the
HOLD button again to
continue with normal operation.
Offsetting a Measurement
Pressing the OFFSET
button subtracts the two least
significant digits from a selected range. You must not be
in auto range. The multimeter offsets subsequent mea-
surements.
The offset feature is especially useful when you want to
subtract the lead resistance from very low resistance
measurements or detect small voltage, capacitance, or
current variations.
7

Extending the Display Resolution
Once you exceed the count of 1999 on a selected range
you may still interpret the reading up to a count of 2999:
1. Select the next higher range (or auto range) and verify
that the count does riot exceed 299.
2.
Return to the lower range. Interpret the flashing "1" as
a "2" and read the lower three digits.
Selecting a Range
Press RANGE
to make repeated measurements without
automatically ranging. The first press selects the same
range and removes the AUTO
symbol. Continue to press
the RANGE button to step through the available ranges.
Press and hold the RANGE button for 2 seconds to
return to auto range.
If you apply a voltage that exceeds the maximum reading
of the display, the multimeter flashes the most significant
digit to indicate overrange. Select a higher range or auto
range to display the measurement.
Resetting the Display
If you leave the multimeter on longer than 30 minutes
without using it, the display will automatically turn off. To
return the display without disturbing any other setup,
press RESET (RANGE).
8
Using the Tilt Stand and Holster Hook
Swing the stand out for easier meter reading.
Swing the upper holster hook out and
hook it over a door or mount the
multimeter to a vertical surface with a
screw.
Figure 2: Using the Tilt Stand and Holster Hook
9

Replacing the Battery
The meter uses a single 9 V battery. Refer to Figure 4,
and use the following procedure to replace the battery:
1. Disconnect the test leads from any circuit under test
and turn off the meter.
2. Remove the test leads and the protective holster from
the meter.
3. Lay the meter face down on a work surface that will
not damage the meter face.
4. Remove the screw from the case bottom using a small
Phillips screwdriver.
5. Gently lift the case bottom at the end nearest the LCD
until it unsnaps from the case top.
6. Lift the battery from the case top, and carefully
disconnect the battery connector from the battery.
7. Snap the battery connector to the terminals of the
replacement battery, and replace the battery in the
case top.
8.
Replace the case top. Make sure the battery leads do
not get pinched between the case top and case
bottom. Make sure all the gaskets properly seat and
the two snaps on the case top engage.
9.
Reinstall the screw in the case bottom.
Using the Probe Holders
(
1
Figure 3: Using the Probe Holders
10 11

Case
Bottom
Case Top
9 V
Battery
Figure 4: Replacing the Battery
Replacing the Fuses
Refer to Figure 5, and use the following procedure to
examine or replace the meter fuses:
1. Perform steps 1 through 5 of the Replacing the Battery
procedure on page 11.
2.
Lift the circuit board from the case top. Do not remove
the screws from the circuit board.
3. Remove a defective fuse by gently prying one end of
the fuse loose and sliding the fuse out of the fuse
holder.
4. Install a new fuse of the same size and rating. Make
sure the new fuse is centered in the fuse holder.
A CAUTION.
To prevent product damage, make sure
Lathat the rotary switch and circuit board switch are
both in the OFF position. Notice the pointing
direction of the rotary switch and circuit board switch
are 180 opposite each other
5. Replace the case top. Make sure all the gaskets
properly seat and the battery leads are not pinched
between the two halves of the case. Make sure the
two snaps on the case top engage.
6. Reinstall the screw in the case bottom.
12
13

Case
Bottom
Case
Top
1 A
Fuse
13A
Fuse
Replacement Parts
Table 1 provides a list of replacement parts for the
DMM155 and DMM157 Digital Multimeters. For further
information about the availability of replacement parts,
contact your nearest Tektronix sales office.
Table 1: Replacement Parts
Item Qty
Description Part Number
Battery 1
9V 146-0017-00
Fuse
1
1A, 600 VRAS
159-0337-00
Fuse
1
13A, 600 VRMS
159-0357-00
Test Lead
Set
1 Test leads for input
connectors
196-3408-XX
Protective
Cover
1
Holster 118-9023-XX
Manual
1
Instructions 070-8943-XX
Figure 5: Replacing the Fuses
14
15

Specifications
Accessories
Test leads (pair), protective hol-
General Characteristics
ster, battery, and instructions
31, digit Liquid Crystal Display
(LCD) With a maximum reading
of 1999. Extended resolution of
2999 counts is possible in manu-
al range mode. In the extended
resolution operating mode,
readings above 1999 are dis-
played with a blinking "1" most
significant digit. The blinking "1"
should be interpreted as the digit
2. The three least significant dig-
its display data normally.
Automatic; positive implied, neg-
ative indicated
"1" or "—I" blinks
The"
"symbol is displayed
when the battery voltage drops
below the operating voltage
level.
2 times/second
0 C to +35 C, 0-80% R.H.
35' C to +50 C, 0-60% R.H.
—20
-
C to +60 C, 0-80% R.H.
with battery removed from the
multimeter
Single standard 9 V battery:
NEDA 1604, J1S006P, or IEC6F22
Alkaline 400 hours
165 mm x 85 mm x 38 mm
(6.5 in x 3.3 in x 1.5 in)
with holster
DMM155: 380g (13.40z)
DMM157: 390 g (13.8 oz)
Measurement Ranges and Accuracies
Accuracies are ± (% reading + number of digits) at 23° C
± 5 C, at less than 75% R.H. (relative humidity).
DC Volts
Ranges
200 mV, 2 V, 20 V, 200 V, 600 V
Accuracy (DMM155)
200 mV range: ± (1.0% reading + 2 digits)
2 V. 20 V, 200 V, 600 V ranges:
± (0.7% reading + 2 digits)
Accuracy (DMM157)
200 mV range: ± (0.8% reading + 2 digits)
2 V, 20 V, 200 V, 600 V ranges:
± (0.5% reading + 2 digits)
Input Impedance
10 MO paralleled by less than 100 pF
Overload Protection 600 VDCNAC
R ms all ranges
Resolution (by range)
200 mV
100 pV
2V
1 mV
20V
10 mV
200V
100 mV
600V
1 V
AC Volts
Ranges
2 V, 20 V, 200 V, 600 V
Accuracy (DMM155) ± (1.7% reading + 4 digits)
50 Hz to 400 Hz
Accuracy (DMM157) ± (1.5% reading + 4 digits)
50 Hz to 400 Hz
Input Impedance
10 MO paralleled by less than
100 pF
Overload Protection 600 VDCNACRms all ranges
Display
Polarity Indication
Overrange Indication
Low Battery Indication
Sampling Rate
Operating Temp.
Storage Temp.
Power Supply
Battery Life
Dimension (HxWxD)
Weight (including
battery & holster)
16
17

•
Accuracy (DMM157)
Resolution (by range)
2V
20 V
200V
600 V
DC Current
Ranges
Accuracy (DMM155)
Accuracy (DMM157)
Overload Protection
mA input
10A input
Resolution (by range)
2 mA
200 mA
10 A
AC Current
Ranges
Accuracy (DMM155)
1 mV
10 mV
100 mV
1 V
2 mA, 200 mA, 10 A (10 A range:
30 seconds maximum above
10 A input up to 13A)
2 mA, 200 mA ranges:
± (1.2% reading + 2 digits)
10 A range:
± (2.5% reading + 5 digits)
2 mA, 200 mA ranges:
± (1.0% reading + 2 digits)
10 A range:
± (2.5% reading + 3 digits)
1 A (240 V) fast-blow fuse
13 A (240 V) fast-blow fuse
1A
100 pA
10 mA
2-mA, 200 mA, 10 A (10 A range:
30 seconds maximum above
10 A input up to 13A)
2 mA, 200 mA ranges:
± (1.7% reading + 4 digits)
50 Hz to 400 Hz
10 A range:
± (2.9% reading + 7 digits)
50 Hz to 400 Hz
2 mA, 200 mA ranges:
± (1.5% reading + 4 digits)
50 Hz to 400 Hz
10 A range:
± (2.9% reading + 5 digits)
50 Hz to 400 Hz
1 A (240 V) fast-blow fuse
13 A (240 V) fast-blow fuse
Overload Protection
mA input
10 A input
Resolution (by range)
2 mA
200 mA
10 A
Resistance
Ranges
1 pA
100 pA
10 mA
200 0, 2 kO, 20 kO, 200 kO, 2 MO,
20 MO. (20 MO range measures
approximately 2 MO to 20 MO
only.)
Accuracy (DMM155)
20 MO Range
200 0 Range
Other Ranges
Accuracy (DMM157)
20 MO Range
200 0 Range
Other Ranges
Overload Protection
Test Voltage
Low-Power Ohms
Open-Circuit
Voltage
High-Power Ohms
Open-Circuit
Voltage
± (2.5% reading +
4 digits)
± (1.2% reading + 2 digits)
± (1.0% reading + 2 digits)
± (1.9% reading + 4 digits)
± (1.0% reading + 2 digits)
± (0.8% reading + 2 digits)
600 VDC/VAC R
ms all ranges
Approximately 450 mV
Approximately 900 mV
19
18

Resolution (by range)
200 0
0.10
2k0
10
20k0
100
200 k0
100 0
2 MO
1 k0
20 MO
10 k0
Continuity Check
Threshold
The beeper sounds if the resis-
tance of the circuit measured is
< 25 0 and turns off at > 200 0
Beeper Frequency 2 kHz
Overload Protection 600 VDCNACRms
Diode Test
Test Current
1.6 mA maximum
Test Voltage
3.3 V maximum open circuit
Overload Protection 600 VDCNACRms
Capacitance (DMM157)
Ranges
2 pF, 20 pF, 200 pF
Accuracy
± (1.9% reading + 5 digits)
Resolution (by range)
2 pF
1 nF
20 pF
10 nF
200 pF
100 nF
Overload Protection 600 VDCNACRms all ranges
Auto Power Off
The multimeter will automatically
shut off in about 30 minutes from
the last function or mode
change. The multimeter will turn
on again when another range is
selected or any key switch is
pressed.
WARRANTY
Tektronix warrants that this product will be free from
defects in materials and workmanship for a period of
three (3) years from the date of shipment. If any such
product proves defective during this warranty period,
Tektronix, at its option, either will repair the defective
product without charge for parts and labor, or will provide
a replacement in exchange for the defective product.
In order to obtain service under this warranty, Customer
must notify Tektronix of the defect before the expiration of
the warranty period and make suitable arrangements for
the performance of service. Customer shall be
responsible for packaging and shipping the defective
product to the service center designated by Tektronix,
with shipping charges prepaid. Tektronix shall pay for the
return of the product to Customer if the shipment is to a
location within the country in which the Tektronix service
center is located. Customer shall be responsible for
paying all shipping charges, duties, taxes, and any other
charges for products returned to any other locations.
This warranty shall not apply to any defect, failure or
damage caused by improper use or improper or
inadequate maintenance and care. Tektronix shall not be
obligated to furnish service under this warranty a) to
repair damage resulting from attempts by personnel
other than Tektronix representatives to install, repair or
service the product; b) to repair damage resulting from
improper use or connection to incompatible equipment;
or c) to service a product that has been modified or
integrated with other products when the effect of such
modification or integration increases the time or difficulty
of servicing the product.
20

THIS WARRANTY IS GIVEN BY TEKTRONIX WITH
RESPECT TO THIS PRODUCT IN LIEU OF ANY
OTHER WARRANTIES, EXPRESSED OR IMPLIED.
TEKTRONIX AND ITS VENDORS DISCLAIM ANY
IMPLIED WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE.
TEKTRONIX' RESPONSIBILITY TO REPAIR OR
REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND
EXCLUSIVE REMEDY PROVIDED TO THE
CUSTOMER FOR BREACH OF THIS WARRANTY.
TEKTRONIX AND ITS VENDORS WILL NOT BE
LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL,
OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF
WHETHER TEKTRONIX OR THE VENDOR HAS
ADVANCE NOTICE OF THE POSSIBILITY OF SUCH
DAMAGES.