Transistor Testing; Continuity Test; Measuring Temperature; Specification - Sealey Professional MM20 Instructions

3.6.

TRANSISTOR TESTING

3.6.1. Set the rotary switch to the hFE position.
3.6.2. Determine whether the transistor to be tested in NPN or PNP type and locate the Emitter, Base and Collector leads. Insert leads of the transistor into
the correct holes in the transistor testing socket.
3.6.3. The meter will show the approximate hFE value at test conditions of base current 10µA and Vce 3V.
3.7.

CONTINUITY TEST

3.7.1. Connect the black lead to the COM input socket and the red lead to the ºCVΩmA input socket (the polarity of the red lead is ‘+’).
3.7.2. Set the rotary switch to the
than 50Ω) the built-in buzzer will sound.
3.8.

MEASURING TEMPERATURE

3.8.1. Set the rotary switch to the
3.8.2. Insert the red lead of the K-type thermocouple plug into the ºCVΩmA input socket on the front panel and the black lead into the COM. Now touch the
object to be measured with the thermocouple probe.
WARNING! To avoid electric shock, ensure that the thermocouple has been removed before changing to another function measurement.
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4.

SPECIFICATION

RESISTANCE
Range Accuracy
200Ω ±0.8% of reading ±3 digits
2kΩ ±0.8% of reading ±2 digit
20kΩ ±0.8% of reading ±2 digit
200kΩ ±0.8% of reading ±2 digit
2MΩ ±1.0% of reading ±2 digit
Maximum open circuit voltage: 3.2V
Overload protection: 250V dc or rms. as for all
ranges
DC VOLTAGE
Range Accuracy
200mV ±0.5% of reading ±2 digits
2V ±0.5% of reading ±2 digits
20V ±0.5% of reading ±2 digits
200V ±0.5% of reading ±2 digits
600V ±0.8% of reading ±2 digits
Input impedance: 10MΩ for all ranges.
TRANSISTOR hFE TEST (0-1000)
Range Test Range Test Current
NPN & PNP 0-1000 1b=10 µA
4.1. Accuracy Calculation
Example: Test reading on 200Vdc range is 56.4V. Accuracy is ±0.5% of reading ±2 digit.
Reading ±2 digit = 56.4 ±2 on the last figure i.e. 56.2 to 56.6V.
±0.5% on this range gives 56.2 - 0.5% to 56.6 + 0.5% or 55.9 to 56.9V. Therefore the actual voltage lies between 55.9 and 56.9V.
Note: Accuracy is specified for a period of one year after calibration and at 18
5.

MAINTENANCE

WARNING! Before attempting to open the case, ensure that test leads have been disconnected from measurement circuits to avoid electric shock hazard.
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5.1. For continued protection against fire, replace fuse only with another of the same rating (F200mA/250V Quick Acting). Fuse is located under the circuit board. To
gain access to the fuse, remove the protective rubber boot and the two screws from the rear of the meter. Lift off the rear cover, replace the fuse and re-assemble in
reverse order.
5.2. If the battery sign
section 5.1 but replacing the battery (9V PP3) instead of the fuse.
5.3. SPARE PARTS
MM20.01 TEST LEADS FOR MM20
MM20.02 FUSE (0.5A) FOR MM20
MM20.03 PROBE FOR MM20
6.

DECLARATION OF CONFORMITY

Declaration of Conformity We, the sole UK importer, declare that the product listed below is in conformity with the following standards and directives.
DIGITAL MULTIMETER
Model: MM20
89/336/EEC EMC Directive
73/23/EEC Low Voltage Directive
93/68/EEC CE Marking Directive
NOTE: It is our policy to continually improve products and as such we reserve the right to alter data, specifications and component parts without prior notice.
IMPORTANT: No liability is accepted for incorrect use of this equipment.
WARRANTY: Guarantee is 12 months from purchase date, proof of which will be required for any claim.
INFORMATION: For a copy of our latest catalogue and promotions call us on 01284 757525 and leave your full name and address, including postcode.
01284 757500
position and connect the test leads across the two points of the circuit under test. If continuity exists (i.e. resistance less
C position and the LCD display will show the ambient temperature.
O
AC VOLTAGE
Resolution Range
0.1Ω 200V ±1.2% of rdg ± 10 digits
1Ω 600V ±1.2% of rdg ± 10 digits
10Ω
100Ω
1kΩ Overload protection: 600V dc or rms. ac for all
ranges.
Frequency range: 40Hz - 400Hz
Response: Average calibrated in rms sine wave.
TEMPERATURE
Resolution
Range Accuracy
0.1mV
-20° to 0°C 0° to 400°C 400°C to 1000°C
1mV
± 10.0%
-20°C
10mV
of rdg ± 2
to
0.1V
digits
1000°C
1V
Test Voltage
Vce=3V
appears on the LCD display, it indicates that the battery should be replaced. Repeat the steps detailed in
Sole UK Distributor,
Sealey Group,
Bury St. Edmunds, Suffolk.
01284 703534
Accuracy Resolution
100mV
1V
± 1.0% of
± 2.0% of rdg
rdg ± 3
digits
C to 28 C with a relative humidity of 80%.
O O
The construction file for this product is held by the Manufacturer and may be inspected,
by a national authority, upon request to Jack Sealey Ltd.
Signed by Mark Sweetman
For Jack Sealey Ltd. Sole UK importer of Sealey Professional Tools.
sales@sealey.co.uk
e-mail
DC CURRENT
Range Accuracy
2mA ±1.5% of reading ±1 digit
20mA ±2.0% of reading ±5 digits
200mA ±1.5% of reading ±1 digits
10A ±2.0% of reading ±5 digits
Overload protection: F200mA/250V fuse
10A range unfused
Resolution
1°C
22 November 2004
www.sealey.co.uk
Web
Resolution
1µA
10µA
0.1mA
10mA
MM20 - 1 - 221104