Extech Instruments 38070 User Manual

User's Guide
Analog Multimeter
Model 38070
Introduction
Congratulations on your purchase of the Extech model 38070 Analog
Multimeter. This device measures AC/DC Voltage, DC Current, Resistance,
and dB, displaying measurements in analog format. Properly used, this meter
will provide many years of reliable service.
Support line (781) 890-7440
Technical support: Extension 200; E-mail: support@extech.com
Repair & Returns: Extension 210; E-mail: repair@extech.com
Product specifications subject to change without notice
For the latest version of this User's Guide, Software updates, and other up-
to-the-minute product information, visit our website: www.extech.com
Extech Instruments Corporation, 285 Bear Hill Rd., Waltham, MA 02451
WARNING: USE EXTREME CAUTION IN THE USE OF THIS DEVICE.
Improper use of this device can result in injury or death. Follow all safeguards
suggested in this manual in addition to the normal safety precautions used in
working with electrical circuits. DO NOT service this device if you are not
qualified to do so.

Safety Instructions

This meter has been designed for safe use, but must be operated with caution.
The rules listed below must be carefully followed for safe operation.
1. NEVER apply voltage or current to the meter that exceeds the specified
maximum:
Input Protection Limits
Function Maximum Input
V DC or V AC 500V AC and DC
mA DC 500mA DC
Resistance 50V DC/AC
2. USE EXTREME CAUTION when working with high voltages.
3. DO NOT measure voltage if the voltage on the "COM" input jack exceeds
500V above earth ground.
4. NEVER connect the meter leads across a voltage source while the
function switch is in the current or resistance mode. Doing so can
damage the meter.
5. ALWAYS discharge filter capacitors in power supplies and disconnect the
power when making resistance tests.
6. ALWAYS turn off power and disconnect test leads before opening the
covers to replace the fuse or battery.
7. NEVER operate the meter unless the back cover and the battery and fuse
covers are in place and fastened securely.
8. If the equipment is used in a manner not specified by the manufacturer,
the protection provided by the equipment may be impaired.

Safety Symbols

This symbol adjacent to another symbol, terminal or operating
device indicates that the operator must refer to an explanation
in the Operating Instructions to avoid personal injury or damage
to the meter.
This WARNING symbol indicates a potentially hazardous
WARNING
situation, which if not avoided, could result in death or serious
injury.
This CAUTION symbol indicates a potentially hazardous
CAUTION
situation, which if not avoided, may result damage to the
product.
MAX
This symbol advises the user that the terminal(s) so marked
500V must not be connected to a circuit point at which the voltage
with respect to earth ground exceeds 500V.
This symbol adjacent to one or more terminals identifies them
as being associated with ranges that may, in normal use, be
subjected to particularly hazardous voltages. For maximum
safety, the meter and its test leads should not be handled when
these terminals are energized.
This symbol indicates that a device is protected throughout by
double insulation or reinforced insulation.
Controls and Jacks
1. Scale
2. Pointer
3. Scale zero adjust
4. Ohms zero adjust
5. Rotary function switch
Positive V, mA and Ω input jack
6.
7. COM input jack

Specifications

Function Range
DC Voltage 500V
250V
50V
10V
AC Voltage 500V
(50/60Hz)
250V
50V
10V
DC Current 250mA
50Ma
0.5mA
Resistance Rx10 (10,000Ω)
Rx1k (1,000,000Ω)
Decibels -10 to +56 dB (4 ranges)
500V AC/DC
Max input voltage
2kΩ/V
Input Sensitivity,
50/60Hz
Frequency Range
0ne (1) 1.5V AA battery
Battery
500mA/250 fast blow (5mmx20mm)
Fuse
o o o
Operating Temperature 41 F to 104 F (5 C to 40
o o o
14 F to 122 F (-10 C to 50
Storage Temperature
Max 80% up to 87ºF (31ºC) decreasing linearly to
Operating Humidity
50% at 104ºF (40ºC)
<80%
Storage Humidity
7000ft. (2000meters) maximum.
Operating Altitude
3.88oz (110g)
Weight
3.82x3.34x1.3" (97x65x33mm)
Size
For indoor use and in accordance with the
Safety
requirements for double insulation to IEC1010-1
(1995): EN61010-1 (1995) Overvoltage Category II
500V, Pollution Degree 2. UL, CE Approved
1
2
3
4
5
6
7
Accuracy
± 4% of full scale
± 5% of full scale
± 4% of full scale
± 5% of full scale
0dB=1mW in 600Ω
o
C)
o
C)