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CAT III
(Measurement Category III)
is applicable to test and
measuring equipment connected to the distribution part of
the building’s low-voltage MAINS installation.
CAT IV (Measurement Category IV)
is applicable to test and
measuring equipment connected at the source of the
building’s low-voltage MAINS installation.
For further information on measurement categories
see page 21 or visit
www.martindale-electric.co.uk/measurement_categories.php
Equipment complies with relevant EU Directives
End of life disposal of this equipment should be in accordance
with relevant EU Directives.
1.2 Precautions
This product has been designed with your safety in mind, but please
pay attention to the following warnings and cautions before use.
Warnings
In order to avoid the danger of electrical shock, it is important that
proper safety measures are taken when working with voltages
exceeding 30V AC rms, 42V AC peak or 60V DC.
Where applicable other safety measures such as the use of protective
gloves, goggles etc. should be employed.
The multimeter must only be used by a skilled and competent person
who is familiar with the relevant regulations, the safety risks involved
and the consequent normal safe working practices, and under the
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conditions and for the purposes for which it has been constructed
and specified.
Before each use the multimeter and any associated test leads
and accessories should be examined for damage, cracks, cuts or
scratches.
Do not use
if damaged in any way.
Make sure the multimeter and test leads are dry, clean and free from
dust, grease and moisture while in use to avoid the danger from
electric shock due to surface leakage.
Always test this unit on an appropriate proving device or a known
good voltage source before and after using it to determine if a
hazardous voltage exists in a circuit to be tested.
Do not use
the
unit if it does not function correctly during proving.
Measuring/testing for a voltage/current that exceeds the specified
limits of the unit may damage the unit and may expose the operator
to a shock hazard. Always check the unit’s specified limits before
use.
The multimeter must only be used on CAT IV installations up to
600V to earth, CAT III and CAT II installations up to 1000V to earth,
and within the operating temperature and humidity range specified.
The CAT III 1000V marking does not mean the clamp meter can
be used to 1000V AC rms, but that it will be safe to the user if
inadvertently connected across a voltage up to 1000V AC rms to
earth.
If the removable probe tip caps are not fitted to the probes of the test
leads, their measurement category becomes CAT II 1000V, and they
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must not be used
on CAT III or CAT IV installations to avoid the
risk of shorting high energy circuits and arc flash.
When this unit is used in combination with test leads, the
measurement category of the combination is the lower
measurement category of either this unit or the test leads used.
Likewise if test lead accessories such as crocodile clips are also
used, the measurement category will be the lowest measurement
category in that combination.
Do not use
if the battery compartment cover is not fitted.
When using test leads,
always
keep your fingers behind the finger
guard on the test lead probe.
To avoid electrical shock, and damage to the multimeter, do not use
the multimeter and the associated temperature probe when voltages
at the measurement surface exceed 30V AC rms or 60V DC.
Cautions
Avoid severe mechanical shock or vibration and extreme
temperature.
When using test leads avoid excessive stresses to the cable entry
points at the probe and 4mm plug connector.
To avoid burns or damage to equipment, do not take temperature
measurements inside microwave ovens.
To avoid possible corrosion from a leaking battery, remove the
battery when the unit is not in use for an extended period.
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2. INTRODUCTION
2.1 Inspection
Examine the shipping carton for any sign of damage. Inspect the
unit and any accessories for damage. If there is any damage then
consult your distributor immediately.
2.2 Description
The Martindale MM94 has the following measurement functions:
True rms AC voltage to 750V
DC voltage to 1000V
True rms AC current to 20A
DC current to 20A
Resistance to 60M
:
Conductance to 60nS
Capacitance to 6mF
Frequency to 10MHz
Duty cycle
Temperature (Type K thermocouple)
Continuity with audible indication
Diode testing
Further functions are:
Display hold
Min/Max indication
Peak hold measurement
Selectable high frequency rejection
Relative function
Selectable 6000 or 60000 count display
Display backlight
