3B SCIENTIFIC PHYSICS Escola 30 User manual

3B SCIENTIFIC®PHYSICS
1
Analogue Multimeter Escola 30 1013526
Instruction sheet
12/16 SD/JS
1 Connection sockets
2 Display with mirror scale
3 Slotted screw for zero calibration
4 Calibration trimmer for setting centre zero point
5 Rotary switch to select the measurement range
6 Three-way switch
1. Description
The ESCOLA 30 is an electronic meter with a mir-
rored dial for measurements of current and volt-
age involving analogue techniques for schools
and training use.
The meter allows measurements of AC and DC
current and voltage values and the zero point can
be set up in the centre of the scale for measure-
ment of DC quantities. AC quantities with frequen-
cies of up to 40 kHz can be measured. All the pos-
sible measuring ranges can be selected by means
of a single rotary switch.
The excess current protection of the Escola 30 au-
tomatically limits the power when overloaded. Af-
ter a brief cooling phase, the multimeter au-toma-
tically switches on again.
The use of a robust moving coil galvanometer and
a mechanically resilient casing make it pos-sible
to use the equipment even under highly challen-
ging conditions. This means that this equipment is
suitable for use in schools by children of all years.
2. Initial calibration
Set up the ESCOLA 30 meter either horizon-
tally or vertically.
Do not connect measuring leads to begin with.
Set the three-way switch to .
The needle will point to the zero point of the dial.
If it does not, the amount of charge of the battery
should be checked.

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3. Safety instructions
The analogue nultimeter Escola 30 conforms tosa-
fety regulations for electrical measurement, control
and laboratory equipment, as specified in DIN EN
61010-1, protection class 2 and to measuringcate-
gory CAT I for up to 30 V. It is not approved for
measurements on low-voltage distribution
equipment, such as sock-ets, fuses, etc. The nom-
inal voltage must not exceed 30 V.
The meter is intended for measurements within its
measuring ranges and in a measuring environ-
ment as described in detail in the course of this
manual. Safe operation of the multimeter is gua-
ranteed if it is solely used as specified. Safety can-
not be guaranteed, however, if the multimeter is
used incorrectly or handled without due care and
attention.In order to avoidserious injury due to cur-
rent or voltage shocks, the following safety instruc-
tions are to be observed at all times:
Carefully read the instruction manual before
using the multimeter and obey the instruc-
tions therein.
The assumption needs to be made that unfore-
seen voltages may be present in the vincinity of
objects being measured (e.g. faulty equipment).
Before using the multimeter, check the hou-
sing and measuring leads for damage and if
there should be any malfunctions or visible
damage, the multimeter is not to be used. Pay
specific attention to the insulation for the mea-
suring sockets.
The authorised measuring range is not to be
exceeded. If measurements are made when
the magnitude of the variable is unknown, al-
ways select a large measuring range before
shifting down to lower ones.
Before using the analogue multimeter to
check that a voltage source is not exhibiting
any actual voltage, check that the meter is
working properly by selecting the battery test
function.
When measuring current, make sure the elec-
tricity is turned off before the analogue multi-
meter is connected into the circuit.
When making measurements, always con-
nect the ground lead first. Disconnect the sig-
nal measurement lead before unplugging the
ground.
Turn off the multimeter before opening the
casing, disconnect the power to the circuit and
the measuring leads from the multimeter.
When the multimeter is used by teenagers,
trainees etc., a suitable person should super-
vise to ensure the equipment is used safely.
4. Operation
4.1 To switch on:
Set the three-way switch to or .
4.2 Checking battery charge:
Set the three-way switch to .
Disconnect all measuring leads.
Set the rotary switch to .
If the battery is sufficiently charged, the needle will
point to the following range indication, . If
this is not the case, the battery will need to be re-
placed immediately.
4.3 Zero point calibration:
Set up the analogue multimeter either hori-
zontally or vertically
Set the three-way switch to .
Turn the rotary switch to 30 V=.
Connect the sockets together with a short
connecting lead.
Turn the zero-point trimmer screw to adjust
the zero point as needed.
4.4 Zero point calibration for centre zero
point:
For measurements of DC current and voltage, the
zero point of the scale can be moved to the centre
of the dial.
Disconnect all measuring leads.
Set the three-way switch to and turn the
rotary switch to a DC current or voltage range,
Use the zero-point trimmer to line up the nee-
dle precisely in the centre of the dial.
4.5 To switch off:
Set the three-way switch to .
When the meter is turned off, the needle points to
.
4.6 If a measurement is interrupted by battery
cut-out:
After 45 minutes of use, the multimeter is auto-
matically shut off and the needle will then point to
.
To switch back on:
Set the three-way switch of the analogue mul-
timeter to off and then use it to turn the meter
back on.

3
5. Current measurements
The Escola 30 is not permitted to be
used for measurements on low-volt-
age mains distribution equipment,
suchasmainssockets,circuitbreakers
and fuses etc.
The nominal voltage of the electricity
source must not exceed 30 V and its
nominal current must be no higher
than 3 A.
The multimeter is to be connected
in series with the load on the side
where the voltage with respect to
ground is lowest!
Turn off the circuit before the Es-
cola 30 meter is connected into it.
Connect the side with the lower potential to
the left-hand socket.
Connect the common/ground lead first and
only then the signal lead.
5.1 DC currents (mA=):
Set the rotary switch to the desired DC current
range. If measurements are made when the
magnitude of the variable is unknown, always
select a large measuring range before shifting
down to lower ones.
Set the three-way switch to or, if the
zero point is to be set in the centre, to .
5.2 AC currents (mA~):
Set the rotary switch to the desired AC current
range. If measurements are made when the
magnitude of the variable is unknown, always
select a large measuring range before shifting
down to lower ones.
Set the three-way switch to .
6. Voltage measurements
The Escola 30 is not permitted to be
used for measurements on low-volt-
age mains distribution equipment,
suchasmainssockets,circuitbreakers
and fuses etc.
The nominal voltage of the voltage
source must not exceed 30 V.
Connect the side with the lower potential to
the left-hand socket.
Connect the common/ground lead first and
only then the signal lead.
6.1 DC voltages (V=):
Set the rotary switch to the desired DC voltage
range.If measurements are made when the
magnitude of the variable is unknown, always
select a large measuring range before shifting
down to lower ones.
Set the three-way switch to or, if the
zero point is to be set in the centre, to .
6.2 AC voltages (V~):
Set the rotary switch to the desired AC voltage
range.If measurements are made when the
magnitude of the variable is unknown, always
select a large measuring range before shifting
down to lower ones.
Set the three-way switch to .
Symbols for measuring ranges
mA=
DC (unit mA)
mA~
AC (unit mA)
V=
DC voltage (unit V)
V~
DC voltage (unit V)
~
~
~~
~
~
~~

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7. Technical data
Display:
Scales: 0 … 10, linear
0 … 3, linear
Type: Mirror scale
Scale length: 80 mm
Pointer deflection: 0…90°
Electrical
zero-point offset: in all DC ranges
Measurements:
Voltage ranges: 0.3, 1, 3, 10, 30 VAC/DC
Internal resistance: 10 k/V
Current ranges: 1, 10, 100, 1000,
3000 mA AC/DC
Voltage drop when
measuring current: 100 mV approx. AC/DC
Reference conditions:
Ambient temperature: 23 °C
Operating alignment: Vertical/horizontal
Signal form: Sine (1% max. discrep-
ancy)
Peak factor:
2
Frequency range: 40 Hz … 50 Hz … 5 kHz
Accuracy (at reference conditions):
DC quantities: Class 2
DC with
zero-point offset: Class 5
AC quantities: Class 3
Extended frequency range (class 10):
0.3 –30 V: 40 Hz … 50 Hz … 40 kHz
1 –3000 mA: 40 Hz … 50 Hz … 40 kHz
Overload protection:
Current and voltage ranges:
reversible for up to ±50 V AC/DC peak-to-peak
value and max. 40 A.
Electrical safety:
Safety specifications: EN 61010-1
Measuring category: CAT I: 30 V
Contamination level: 2
Protection type: IP20
Connectors: 4-mm safety sockets
Power supply:
Battery: 1x 1.5 V, AA IEC LR6
Automatic cut-off after: 45 min ± 10 min
Electromagnetic compatibility:
Interference emission: EN 55011:2009
Interference resistance: EN 61326-1:2013
Operating conditions:
Ambient temperature: 5 °C ... 23 °C … 40°C
Storage temperature: -20 … 70°C
Relative humidity: <85% with no condensa-
tion
General data:
Shock test: max. 147 m/s²
Dimensions: 100x150x50 mm3 ap-
prox.
Weight: 300 g approx..
Measuring categories according to DIN EN
61010-1.
CAT I or unstipulated: Approved for measure-
ments in circuits which are not directly connected
to the low voltage mains grid (e.g. batteries).
CAT II: Approved for measurements in circuits
which are directly connected, by a mains lead and
plug for instance, to the low voltage mains grid
(e.g. household or office appliance and lab
equipment).
CAT III: Approved for measurements in circuits
which are part of a building’s wiring installation
(e.g. stationary consumers, distribution terminals,
appliances connected directly to the distribution
box).
CAT IV: Approved for measurements in circuits
which are directly connected to the source of the
low voltage mains (e.g. electricity meters, main
service feed, primary excess voltage protection).

3B Scientific GmbH ▪ Rudorffweg 8 ▪ 21031 Hamburg ▪ Germany ▪ www.3bscientific.com
Subject to technical amendments
© Copyright 2016 3B Scientific GmbH
10. Battery, care and maintenance
10.1 Battery testing:
Batteries which are discharged and have not been
used for a while may leak.
Check the amount of charge left in
the battery from time to time.
Flat or leaking batteries should be
removed from the meter.
If the Escola 30 goes unused for a
long period:
Remove the Escola 30’s battery
before reusing.
10.2 Changing the battery:
Before opening the casing:
Turn off the Escola 30.
Disconnect all measuring leads.
The polarity is indicated by plus and minus signs
inside the fuse holder compartment. A mechanical
system ensures the battery makes no contact if it
is inserted the wrong way round.
Unscrew the back of the casing.
Replace flat batteries with 1.5-V alkaline bat-
teries of size AA IEC LR6.
Place the negative pole of the battery on the
spring.
Close casing again.
10.3 Cleaning:
For cleaning, use a soft cloth, slightly mois-te-
ned with alcohol, or a brush.
Electrostatic charging of the display window can
affect the measurements under certain circum-
stances:
To remove such charge, use a soft cloth
slightly soaked in alcohol or a paint brush.
Dirt or moisture in the measurement sockets can
affect readings.
Shake out any dirt that may be in the meas-
urement sockets.
Soak a new swab with isopropyl alcohol and
work around the inside of each measurement
socket.
11. Disposal
The packaging should be disposed of at local
recycling points.
Should you need to dis-
pose of the equipment it-
self, never throw it away in
normal domestic waste. If
being used in private
households it can be dispo-
sed of at the local public
waste disposal authority.
Comply with the applicable regulations for the
disposal of electrical equipment.
Do not dispose of the batteries in the regular
household garbage. Follow the applicable le-
gal regulations (UK: Waste Batteries and Ac-
cumulators Regulations, EU: 2006/66/EC).
12. Symbol legend
Hazard, read instruction sheet
Moving coil galvanometer
Apparatus with electronic amplifier
DC quantities accuracy class 2
AC quantities accuracy class 3
Use in vertical position
Use in horizontal position
Dial position when turned off
Dial position for battery test when bat-
tery charge is satisfactory
Meter on for AC and DC measurements
Meter on for measurements with centre
zero point
Meter switched off
Battery test
EU conformity mark
Electrical safety assured by double in-
sulation
Do not dispose in normal domestic
waste
For use indoors only