CEM DT-912 User manual

OPERATING INSTRUTION
DIGITAL MULTIMETER
10A COM V mA
OFF
600
200
2000
20m
200
m
10A
1.5V
9V
200
2000
20k
200k
2000
k
600
200
20
2000
m
200
m
V AC
A DC
BATT.
CAT III 600V
V DC
HOLD

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2
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 Limits
Function
Maximum Input
VAC
600V DC/AC
V DC or V
AC
600V DC/AC, 200Vrms on 200mV
range
mA DC
200mA 250V fast acting fuse
A DC 10A 250V fast acting fuse
(30 seconds max every 15 minutes)
Resistance
, Continuity
250Vrms for 15sec max
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, resistance, or
diode mode. Doing so can damage the meter.
5. ALWAYS discharge filter capacitors in power supplies

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and disconnect the power when making resistance or
diode tests.
6. ALWAYS turn off the power and disconnect the test
leads before opening the doors to replace the fuse or
batteries.
7. NEVER operate the meter unless the back cover and the
battery and fuse doors are in place and fastened
securely.
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 situation, which if not
avoided, could result in death or serious
injury.
This CAUTION symbol indicates a
potentially hazardous situation, which if not
avoided, may result damage to the
product.
This symbol advises the user that the
terminal(s) so marked must not be
MAX
WARNING
CAUTION

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connected to a circuit point at which the
voltage with respect to earth ground
exceeds (in this case) 500 VAC or VDC.
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
10A COM V mA
OFF
600
200
2000
20m
200
m
10A
1.5V
9V
200
2000
20k
200k
2000
k
600
200
20
2000
m
200
m
V AC
A DC
BATT.
CAT III 600V
V
DC
HOLD
1
6
2
3
7
5
4

5
1. LCD Display
2. Function switch
3. 10A jack
4. COM jack
5. Positive jack
6. Data Hold Button
7. Backlight Button
Note: Tilt stand, fuse and battery compartment are on rear
of unit.
SYMBOLS AND ANNUNCIATORS
•))) Continuity
Diode test
µ micro (amps)
m milli ( volts, amps)
k kilo (ohms)
 Ωohms
VDC volts direct current
VAC volts alternating current
ADC amps direct current
BAT Battery test

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SPECIFICATIONS
Function
Range
Resolution
Accuracy
DC Voltage
(V DC)
200mV
0.1mV
±(0.5% reading + 2
digits)
2000mV
1mV
20V
0.01V
200V
0.1V
±(0.8% reading + 2
digits)
600V
1V
AC Voltage
(V AC)
200V
0.1V
±(1.2% reading + 10
digits
(50/60Hz)
600V
1V
DC Current
(A DC)
2000µA
1µA
±(1.0% reading + 2
digits)
20mA
10µA
200mA
100µA
±(1.2% reading + 2
digits)
10A 10mA ±(2.0% reading + 2
digits)
Resistance
200Ω
0.1Ω
±(0.8% reading + 2
digits)
2000Ω
1Ω
20kΩ
0.01kΩ
200kΩ
0.1kΩ
2000kΩ
1kΩ
±(1.0% reading + 2
digits)
Battery Test
9V
10mV
±(1.0% reading + 2
digits)
1.5V
1mV
NOTE: Accuracy specifications consist of two elements:
•(% reading) – This is the accuracy of the measurement
circuit.

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•(+ digits) – This is the accuracy of the analog to digital
converter.
NOTE: Accuracy is stated at 65oF to 83oF (18oC to 28oC) and
less than 75% RH.
SPECIFICATIONS
Diode Test Test current of 1mA maximum,
open circuit voltage 2.8V DC
typical
Continuity Check Audible signal will sound if the
resistance is less than
approximately 30Ω
Battery Test current 9V (6mA); 1.5V (100mA)
Input Impedance >1MΩ
ACV Bandwidth 45Hz to 450Hz
DCA voltage drop 200mV
Display 3 ½ digit, 2000 count LCD, 1.1”
digits
Overrange indication “1” is displayed
Polarity Automatic (no indication for
positive polarity); Minus (-) sign
for negative polarity.
Measurement Rate 2 times per second, nominal
Low Battery Indication “BAT” is displayed if battery
voltage drops below operating
voltage
Battery one 9 volt (NEDA 1604) battery

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Fuses mA, µA ranges; 0.2A/250V fast
blow
A range; 10A/250V fast blow
Operating Temperature 32oF to 122oF (0oC to 50oC)
Storage Temperature -4oF to 140oF (-20oC to 60oC)
Relative Humidity <70% operating, <80% storage
Operating Altitude 7000ft. (2000) meters maximum.
Weight 255g
Size 150mm x 70mm x 48mm
Safety For indoor use and in accordance
with Overvoltage Category II,
Pollution Degree 2. Category II
includes local level, appliance,
portable equipment, etc., with
transient overvoltages less than
Overvoltage Category III.
BATTERY INSTALLATION
WARNING: To avoid electric shock, disconnect the test
leads from any source of voltage before removing the
battery door.
1. Disconnect the test leads from the meter.
2. Open the battery door by loosening the screw using a
Phillips head screwdriver.
3. Insert the battery into battery holder, observing the correct
polarity.
4. Put the battery door back in place. Secure with the screw.

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WARNING: To avoid electric shock, do not operate the
meter until the battery door is in place and fastened
securely.
NOTE: If your meter does not work properly, check the fuses
and batteries to make sure that they are still good and that
they are properly inserted.
OPERATING INSTRUCTIONS
DATA HOLD BUTTON
The Data Hold function allows the meter to "freeze" a
measurement for later reference.
1. Press the DATA HOLD button to “freeze” the reading on
the indicator. The indicator “HOLD” will be appear in the
display.
2. Press the DATA HOLD button to return to normal
operation.
BACK LIGHT BUTTON
1. The BACK LIGHT button is used to turn the back light on
or off. Press the BACK LIGHT BUTTON to turn the back
light on.
2. Press the BACK LIGHT BUTTON to turn the back light
off.
WARNING: Risk of electrocution. High-voltage
circuits, both AC and DC, are very dangerous and
should be measured with great care.