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 position and connect the test leads across the two points of the circuit under test. If continuity exists (i.e. resistance less
than 50Ω) the built-in buzzer will sound.
3.8. MEASURING TEMPERATURE
3.8.1. Set the rotary switch to the OC position and the LCD display will show the ambient temperature.
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.
p WARNING! To avoid electric shock, ensure that the thermocouple has been removed before changing to another function measurement.
5. MAINTENANCE
4. SPECIFICATION
6. DECLARATION OF CONFORMITY
p WARNING! Before attempting to open the case, ensure that test leads have been disconnected from measurement circuits to avoid electric shock hazard.
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 appears on the LCD display, it indicates that the battery should be replaced. Repeat the steps detailed in
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
For Jack Sealey Ltd. Sole UK importer of Sealey Professional Tools.
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.
Sole UK Distributor,
Sealey Group,
Bury St. Edmunds, Suffolk.
Declaration of Conformity We, the sole UK importer, declare that the product listed below is in conformity with the following standards and directives.
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.
DIGITAL MULTIMETER
Model: MM20
89/336/EEC EMC Directive
73/23/EEC Low Voltage Directive
93/68/EEC CE Marking Directive
Signed by Mark Sweetman 22 November 2004
DC VOLTAGE
Range Accuracy Resolution
200mV ±0.5% of reading ±2 digits 0.1mV
2V ±0.5% of reading ±2 digits 1mV
20V ±0.5% of reading ±2 digits 10mV
200V ±0.5% of reading ±2 digits 0.1V
600V ±0.8% of reading ±2 digits1V
Input impedance: 10MΩfor all ranges.
AC VOLTAGE
Range Accuracy Resolution
200V ±1.2% of rdg ± 10 digits 100mV
600V ±1.2% of rdg ± 10 digits 1V
Overload protection: 600V dc or rms. ac for all
ranges.
Frequency range: 40Hz - 400Hz
Response: Average calibrated in rms sine wave.
RESISTANCE
Range Accuracy Resolution
200Ω±0.8% of reading ±3 digits 0.1Ω
2kΩ±0.8% of reading ±2 digit 1Ω
20kΩ±0.8% of reading ±2 digit 10Ω
200kΩ±0.8% of reading ±2 digit 100Ω
2MΩ±1.0% of reading ±2 digit 1kΩ
Maximum open circuit voltage: 3.2V
Overload protection: 250V dc or rms. as for all
ranges
DC CURRENT
Range Accuracy Resolution
2mA ±1.5% of reading ±1 digit 1µA
20mA ±2.0% of reading ±5 digits 10µA
200mA ±1.5% of reading ±1 digits 0.1mA
10A ±2.0% of reading ±5 digits 10mA
Overload protection: F200mA/250V fuse
10A range unfused
Range Accuracy Resolution
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 18OC to 28OC with a relative humidity of 80%.
-20° to 0°C 0° to 400°C 400°C to 1000°C
1°C
-20°C
to
1000°C
± 10.0%
of rdg ± 2
digits
± 1.0% of
rdg ± 3
digits
± 2.0% of rdg
TEMPERATURE
TRANSISTOR hFE TEST (0-1000)
Range Test Range Test Current Test Voltage
NPN & PNP 0-1000 1b=10µA Vce=3V
01284 757500 sales@sealey.co.uk www.sealey.co.uk
01284 703534 e-mail Web
MM20 - 1 - 221104
