AEMC 3910 User manual

TRUE RMS POWER METER
ENGLISH User Manual
3 910

Owner’s Record
The serial number for the Model 3910 is located inside the battery com-
partment of the instrument. Please record this number and purchase date
for your records.
TRMS POWER METER MODEL 3910
CATALOG #: 2111.27
SERIAL #: _______________________________________________
PURCHASE DATE: ________________________________________
DISTRIBUTOR: ___________________________________________

Table of Contents
1. INTRODUCTION............................................................................... 2
1.1 International Electrical Symbols................................................3
1.2 Receiving Your Shipment..........................................................3
1.3 Ordering Information.................................................................3
1.3.1 Accessories and Replacement Parts............................3
2. PRODUCT FEATURES ...................................................................... 4
2.1 Description................................................................................4
2.2 Control Features .......................................................................5
2.3 Display Features.......................................................................7
2.4 Button Functions ......................................................................7
2.4.1 PEAK Button.................................................................7
2.4.2 Memory Button .............................................................8
3. SPECIFICATIONS............................................................................. 9
3.1 ElectricalSpecications ............................................................9
3.2 MechanicalSpecications ......................................................10
3.3 SafetySpecications ..............................................................11
4. OPERATION .................................................................................. 12
4.1 Single-Phase Networks ..........................................................12
4.2 Balanced Three-Phase Networks ...........................................13
4.3 Three-Phase, Four-Wire Networks .........................................14
4.4 Using as a Voltmeter...............................................................15
4.5 Using as an Ammeter .............................................................16
4.6 Measurements: Review of Formulas Used.............................17
5. MAINTENANCE ............................................................................. 18
5.1 Warning...................................................................................18
5.2 Battery Replacement ..............................................................18
5.3 Cleaning..................................................................................18
Repair and Calibration...........................................................................19
Technical and Sales Assistance ............................................................19
Limited Warranty ...................................................................................20
Warranty Repairs...................................................................................20

2 TRMS Power Meter Model 3910
CHAPTER 1
INTRODUCTION
WARNING
These safety warnings are provided to ensure the safety of
personnel and proper operation of the instrument.
• Read this instruction manual completely before attempting
to use or service this instrument and follow all the safety
information.
• Use caution on any circuit: Potentially high voltages and
currents may be present and may pose a shock hazard.
• The instrument must not be operated beyond its specied
operating range.
• Safety is the responsibility of the operator.
• Never open the back of the instrument while connected to
any circuit or input.
• Always make connections from the instrument to the circuit
under test.
• Always inspect the instrument and accessory leads for ser-
viceability prior to use, and replace defective parts immedi-
ately.
• Do not use the meter or any test leads, connectors, probes or
clips if they look damaged.
• Never use the Model 3910 on electrical conductors rated
above 600V.
• On the current probe input, only use the current probe(s)
supplied with the instrument.
• Never use the Model 3910 without its rubber holster.

TRMS Power Meter Model 3910 3
1.1 International Electrical Symbols
Thissymbolsigniesthattheinstrumentisprotectedbydoubleor
reinforced insulation. Use only specied replacement parts when
servicing the instrument.
This symbol on the instrument indicates a WARNING and that
the operator must refer to the user manual for instructions before
operating the instrument. In this manual, the symbol preceding
instructions indicates that if the instructions are not followed, bodily
injury, installation/sample and product damage may result.
Risk of electric shock. The voltage at the parts marked with this
symbol may be dangerous.
1.2 Receiving Your Shipment
Upon receiving your shipment, make sure that the contents are consistent
with the packing list. Notify your distributor of any missing items. If the
equipmentappearstobedamaged,leaclaimimmediatelywiththecar-
rier and notify your distributor at once, giving a detailed description of any
damage. Save the damaged packing container to substantiate your claim.
Do not use an instrument that appears to be damaged.
1.3 Ordering Information
TRMS Power Meter Model 3910........................................ Cat. #2111.27
Includes 3910 power meter, shock-proof safety holster, 500AAC clamp-on current probe, two
5 ft (1.5m) leads, two test probes, two probe grips, batteries (not installed), user manual and
hard carrying case.
1.3.1 Accessories and Replacement Parts
Probe Adaptor...................................................................... Cat. #2118.34
Clamp-on Current Probe Model SR652 (1000AAC)............. Cat. #2113.46
Order Accessories and Replacement Parts Directly Online
Check our Storefront at www.aemc.com for availability

4 TRMS Power Meter Model 3910
CHAPTER 2
PRODUCT FEATURES
2.1 Description
The True RMS Power Meter Model 3910 is designed for today’s electrical
environments. Operation is simple. There are no programming require-
ments or menus, just four push-buttons for direct access. The Model 3910
is auto-ranging and ensures the best range for measurements.
Troubleshooting and measuring power is done simply by connecting two
voltage leads and clamping on the current probe. The Model 3910 is
easier to operate than most DMMs and may even replace your multimeter
for individual voltage or current measurements.
Small and compact in its protective holster, the Model 3910 provides seven
essential power measurement values. Four measurements are displayed
at a time on its extra large multi-display LCD.
The Model 3910 performs current and voltage measurements in True
RMS, and provides immediate readings of power factor (PF), active power
(kW), reactive power (kVar), apparent power (kVA) and frequency (Hz).
The Model 3910 displays Vrms,Arms, kW and PF on the rst screen;
pressing and holding the PAGE button gives access to kVar, kVA and Hz
on a second screen.
ThePeakfunctionallowsselectionofaspecicparameter(A,VorW)for
peak measurement, and also displays the associated values at the par-
ticular peak (for example, the Model 3910 displays the actual V, kW, PF,
kVar, kVA and Hz values when Apeak is selected).
The unique memory function permits not only storing the measurements
at any time, but also comparing subsequent readings by displaying the dif-
ference between the stored values and the new readings. This is helpful in
analyzing and measuring the impact of loads being turned on and off.
A selector switch on the front panel selects power measurements for
single-phase or balanced three-phase, three-wire systems.

TRMS Power Meter Model 3910 5
2.2 Control Features
1
2
3
5
6
7
8
9
4

6 TRMS Power Meter Model 3910
1. SEL Button
Selects the parameter (A, W, V) whose peak is to be measured.
2. MEM Button
Accesses two functions:
• Memory
• Measurements of differences in voltage, current and active power
between stored values and subsequent readings.
3. ON/OFF Switch
Turns the instrument ON or OFF. The Model 3910 takes a few sec-
onds to power up when turned “ON”.
4. Clamp Input
FRB socket for connecting the clamp-on current probe. Use only
speciedcurrentprobes,whichhaveavoltageoutput(1mVAC/AAC).
5. Display
LCD (40x50mm), displays the seven measurements on two pages.
NOTE: A beep sounds when the PAGE, PEAK, SEL or MEM button
is pressed.
6. PEAK Button
Selects “PEAK” measurement mode.
7. PAGE Button
Displays Vrms, Arms, W, PF (or Cos Φ)onpage1automatically;
pressing PAGE gives access to Var, VA and Hz on page 2.
8. 1Ø / 3Ø
Selects the type of network to be tested.
• 1Ø: single-phase
• 3Ø: balanced three-phase, three-wire
9. Voltage Inputs
Two safety input terminals (4mm) for lead connection. Voltage mea-
surement may be made up to 600VAC/DC.

TRMS Power Meter Model 3910 7
2.3 Display Features
When the Model 3910 is switched ON, page 1 is displayed automatically:
• RMS voltage (V)
• RMS current (A)
• Active power (W)
• Power factor (pF) (or Cos Φ)
Hold down the PAGE button to display page 2:
• Reactive power (Var)
• Apparent power (VA)
• Frequency (Hz)
To return to page 1, release the PAGE button
2.4 Button Functions
2.4.1 PEAK Button
When this button is activated, PEAK values of a measurement can be
displayed.
To activate the PEAK mode, press the PEAK button once. The Model
3910 changes initially to peak current measurements and “PEAK A” is
displayed.
Press the SEL button to choose the desired parameter (A, W, V). The SEL
button can only be used after the PEAK button has been activated.
NOTE: The peak measurement is:
• the maximum value for the current (A)
• the maximum value for the active power (W)
• the minimum value for the voltage (V)

8 TRMS Power Meter Model 3910
The Model 3910 stores all the measurements present when peak is
selected.Therstfourmeasurements(V,A,W,PF)aredisplayedonpage
1 and the following three measurements (Var, VA, Hz) on page 2 (press
thePAGEbutton).Forexample,youcanndthevoltage,thepower,etc.,
at the moment when current is at a peak.
In PEAK mode, the typical acquisition time is 400ms. Each new peak is
taken into account as long as the PEAK button is activated. To exit PEAK
mode, press the PEAK button.
2.4.2 Memory Button
This button has two functions:
• First Function - Memory
To store page 1 of the display, press the MEM button
once. “MEM” will show on the display.
Voltage, current, active power and power factor are
stored.
• Second Function - Differential Measurements
Once the values are memorized (MEM is displayed), press the PAGE
button. Page 2 will display the differences between the values in memory
and the values that the instrument continues to measure.
Measurements of differences in voltage, current
and active power.
NOTE: The power factor is no longer displayed.
If the difference between measurements is a nega-
tive value, a minus “-” sign is displayed.
To exit memory mode, press the MEM button again.