MARTINDALE MM45 User manual

Operating Instructions
Model MM45
Digital Multimeter
SAFETY INFORMATION
The following safety information must be observed
to ensure maximum personal safety during the
operation of this meter:
Do not use the meter if the meter or test leads look
damaged, or if you suspect that the meter is not
operating properly.
Never ground yourself when taking electrical
measurements. Do not touch exposed metal pipes,
outlets, fixtures, etc, which might be at ground
potential. Keep your body isolated from ground by
using dry clothing, rubber shoes, rubber mats, or
any insulating material.
Turn off power to the circuit under test before
cutting, unsoldering, or breaking the circuit. Small
amounts of current could be dangerous.
Use caution when working above 60V DC or 30V AC
rms. Such voltages pose a shock hazard.
When using the probes, keep your fingers behind
the finger guards on the probes.
MM45 REV3 7/05
NOTE
This instrument is only to be used by a suitably
trained and competent person.
The symbols used on this instrument are:
Measuring voltage which exceeds the limits of the
multimeter may damage the meter and expose the
operator to a shock hazard. Always recognise the
meter voltage limits as stated on the front of the
meter.
SPECIFICATIONS
Display: 3½ digit liquid crystal display (LCD) with a
maximum reading of 3200.
Analog bar graph: 34 segments with measurements
12 times per second.
Polarity: Automatic,(-) negative polarity indication.
Overrange: “OL” mark indication.
Zero: automatic.
Low Battery Indication: The is displayed when
the battery voltage drops below the operating level.
Measurement rate: 2 times per second, nominal.
Operating environment: 0°C to 50°C at < 70% R.H.
Storage temperature: -20°C to 60°C, 0 to 80% R.H.
with battery removed from meter.
Battery life: 200 hours typical with carbon-zinc.
Battery: Single standard 9-volt battery, MN1604,
NEDA 1604, JIS 006P, IEC 6F22, PP3.
Dimensions: 147mm (H)x 70mm (W)x 39mm (D).
Weight: Approx. 345g (11.8 oz) including holster.
Auto power off: Meter automatically shuts down after
approx. 10 minutes of inactivity.
Accessories: One pair test lead, One spare fuse, 9V
battery (installed) and Operating Instructions.
Range
320mV
3.2V
32V
320V
600V
Range
320µA
3200µA
32mA
320mA
10A
Range
320Ω
3.2kΩ
32kΩ
320kΩ
3.2MΩ
32MΩ
0-2000
Range
320Ω
Voltage
(50/60Hz)
Current
(50/60Hz)
OHM
Diode
Test
Continuity
Check
AC Accuracy
N / A
± 2.0% rdg+4d
AC Accuracy
± 2.5% rdg+4d
± 3.5% rdg+4d
Accuracy
± 2.0% rdg+3d
± 1.5% rdg+3d
± 2.5% rdg+3d
± 5.0% rdg+5d
± 10% rdg+2d
Audible Indication
< approx. 20Ω
Input Impedance
> 1000MΩ
11MΩ
10MΩ
Voltage Burden
0.2V
2V
0.2V
2V
2V
Test Current
< 0.7mA
< 0.13mA
< 13µA
< 1.3µA
< 0.13µA
0.5mA (Vf = 0.6V)
Test Current
< 0.7mA
DC Accuracy
± 1.2% rdg+1d
± 0.8% rdg+1d
± 1.2% rdg+1d
DC Accuracy
± 2.0% rdg+1d
± 3.0% rdg+3d
Resolution
100mΩ
1Ω
10Ω
100Ω
1kΩ
10kΩ
1mV
Resolution
100mΩ
Caution, risk of electric shock
Caution, refer to accompanying
documents
Equipment protected throughout
by Double Insulation (Class II)
Alternating current
Direct current
Ground
z
Maximum Input
600VDC or
600VAC rms
Input Protection
0.5A/250V fuse
10A/250V fuse
Input Protection
500VDC or
500VAC rms
500V DC or AC rms
Input Protection
500V DC or AC rms
~
HIGH ENERGY SYSTEMS
GS38 advises fused test leads to be used when
working on high energy systems. Suitable leads
are Martindale TL55.
The instrument meets the requirements for double
insulation to BS EN 61010-1 at 600V Installation
Category III. Installation Category III (distribution
level) relates to transient overvoltage likely to be
found in fixed installation wiring.

OPERATION
Before taking any measurements, read the Safety
Information Section. Always examine the instrument
for damage, contamination (excessive dirt, grease,
etc.) and defects. Examine the test leads for cracked
or frayed insulation. If any abnormal conditions exist
do not attempt to make any measurements.
Input Warning Beeper
The meter has a beeper that warns the user when
the test lead is in the current socket while the meter
is switched to make a voltage measurement.
Another safety feature to protect the meter and you.
Manually Selecting A Range
The meter also has a manual range mode. In manual
range, you select and lock the meter in a range. To
manually select a range:
Press [RANGE] button to hold the selected range.
Subsequently pressing the [RANGE] button will
select each range in sequence from the lowest to
highest range. Hold the button for 2 seconds to
return to the Autorange Mode.
Mode Switch (DC/AC), /
Press this switch to toggle between DC and AC in
the current measurements. Press this switch to
toggle between thecontinuity/diode modes, if the
function switch is set / to position.
Voltage Measurements
1. Connect the red test lead to the "VΩ" socket and
the black test lead to the "COM" socket.
2. Set the Function switch to the desired voltage type
(DCV) or (ACV) position.
3. Touch the probes to the test points, the range will
change automatically to the level that will display the
input voltage with best resolution.
4. The value indicated in the display window is the
measured value of voltage with proper decimal point
and annunciator indication.
5. For DC, a (-) is displayed for negative polarity;
positive polarity is implied.
Current Measurements
1. Set the Function switch to the desired current
range (µA, mA or 10A) position.
2. To toggle between “DC” and “AC” mode, press
Mode switch. The “DC” or “AC” annunciator is
displayed in the upper left corner.
3. For current measurements less than 320mA,
connect the red test lead to the µA/mA socket and the
black test lead to the COM socket.
4. For current measurements of 320mA or greater,
connect the red test lead to the 10A socket and the
black test lead to the COM socket.
5. Remove power from the circuit under test and
open the normal circuit path where the measurement
is to be taken. Connect the meter IN SERIES with the
circuit.
6. Apply power and read the value from the display.
Resistance Measurements
1. Set the Function switch to the “Ω” position.
2. Turn off power to the circuit under test. External
voltage across the components causes invalid
readings.
3. Connect the red test lead to the “VΩ” socket and
the black test lead to the “COM” socket.
4. Connect the test leads to the point of
measurements and read the value from the display.
Testing Diodes
1. Set the Function switch to / position.
2. Turn off power to the circuit under test. External
voltage across the components causes invalid
readings.
3. To toggle between the continuity/diode modes,
press Mode switch.
4. Touch probes to the diode. A forward-voltage
drop is about 0.6V (typical for a silicon diode).
5. Reverse probes. If the diode is good, “OL” is
displayed. If the diode is shorted, a value near 0mV
will be displayed.
6. If the diode is open, “OL” is displayed in both
directions.
Continuity Measurements
1. Set the Function switch to / to position.
2. Turn off power to the circuit under test. External
voltage across the components causes invalid
readings.
3. To toggle between the continuity/diode modes,
press Mode Switch.
4. Connect the test leads to the two points at which
continuity is to be tested. The buzzer will sound if the
resistance is less than approximately 20Ω.
MAINTENANCE
Battery Replacement
Power is supplied by a 9 volt "transistor" battery.
(NEDA 1604, IEC 6F22, PP3). The appears on
the LCDdisplay when replacement is needed. To
replace the battery, remove the three screws from the
back of the meter and lift off the front case. Remove
the battery from case bottom.
Fuse Replacement
If no current measurements are possible, check for a
blown overload protection fuse. There are two fuses; F1
for the mA socket and F2 for the 10A socket. For access
to fuses, remove the three screws from the back of the
meter and lift off the front case. Replace F1 only with
the original type 0.5A/250V, ceramic, fast acting
fuse. Replace F2 only with the original type
10A/600V ceramic, fast acting fuse. The use of other
fuses may cause damage to the meter, invalidate the
warranty and impair the safety of the user. Domestic
‘Plug Top’ fuses should not be used.
Instrument Repairs and Spare Parts
Apart from the battery and fuses, there are no user
serviceable parts inside. If you suspect that the meter
is not operating properly, please check fuses, battery
and leads.
If the meter is still suspected of being faulty please
contact:
Metrohm House, Penfold Trading Estate,
Imperial Way, Watford, Herts. WD24 4YY, UK.
Tel: [phone] Fax: [phone]
E-mail: [email protected]
Web Site: http://www.martindale-electric.co.uk
WARNING
Remove test leads before changing battery or fuse
Accessories
F1 - 20x5mm 500mA 250V Ceramic -
Ref: FUSE500250 (Pack of 3)
F2 - 1¼ x ¼ ” 10A 600V Ceramic - Ref: FUSE10600
(Pack of 3)
Fused test leads to GS38 specification - Ref: TL55
Soft foam lined carry case - Ref: TC55
MM45 REV3 7/05