Drummond MTL10 User manual

MTL10 & MTL20 TEST LAMPS
Instruction
Manual

ALWAYS READ THESE INSTRUCTIONS BEFORE PROCEEDING
Thank you for buying one of our products. For safety and full
understanding of its benets please read this manual before use.
Technical support is available from [phone] and
[email protected].
CONTENTS
1 Description 1
2 Safety Information 2
2.1 Meaning of Symbols and Markings 2
2.2 Precautions 3
2.3 Safety Advice 5
3 Introduction 6
3.1 Inspection 6
3.3 Accessories 6
4 Operation 7
4.1 Control Elements and Connections 7
4.2 Description of LED Indicators 8
4.3 Operating Duty Ratio 8
4.4 Proving Check 9
4.5 Testing for the Presence of Hazardous Live Voltage 10
4.6 Push Button Switches (MTL20 only) 10
4.7 Interference (Phantom) Voltage 11
5 Maintenance 12
5.1 Probe Replacement 12
5.2 Periodic Testing 12
5.3 Cleaning 12
5.4 Repair and Service 13
5.5 Storage Conditions 13
6 Warranty 14
Measurement Categories
Specications

1
1. Description
The MTL10 and MTL20 test lamps are two-pole voltage indicators /
detectors for universal applications. They are designed to be used
by skilled persons in accordance with safe methods of work, and
are constructed in accordance with the applicable safety standards
to provide safe and reliable indication.
The MTL10 and MTL20 have the following features:
•AC and DC Voltage tests up to 500V AC and 750V DC
•Bright LED indication
•Full voltage indication function without batteries
• PTC thermistor tted in probe to limit current in the event of
cable damage
•Contrasting colour of inner sheath to highlight cable damage
•Ergonomic and robust housing
•Probe tips comply with GS38
•Measurement Category CAT IV 600V
•Constructed in compliance with BS EN 61243-3:2010
•IP64 rated environmental protection for internal electronics

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2. SAFETY INFORMATION
REMEMBER: SAFETY IS NO ACCIDENT
These instructions contain both information and warnings that are
necessary for the safe operation and maintenance of this product. It
is recommended that you read the instructions carefully and ensure
that the contents are fully understood. Failure to understand and
to comply with the warnings and instructions can result in serious
injury, damage or even death.
Particular attention should be paid to the Warnings, Precautions
and Technical Specications.
Please keep these instructions for future reference.
Updated instructions and product information are available at:
www.martindale-electric.co.uk
2.1 Meaning of Symbols and Markings
Caution - risk of danger & refer to instructions
Caution - risk of electric shock
Equipment protected by double or reinforced
insulation (Class II)
Suitable for live working
Alternating current (AC)
Direct current (DC)
ON/OFF (push button)
CAT IV (Measurement Category IV) is applicable to test and
measuring equipment connected at the source of the
building’s low-voltage MAINS installation.

3
For further information on measurement categories refer to page 15
or visit www.martindale-electric.co.uk/measurement_categories.php
Equipment complies with relevant EU Directives
Equipment complies with relevant UK Conformity
Assessed marking
End of life disposal of this equipment should be in
accordance with relevant Directives
ELV Extra low voltage. Voltage below 50V AC or 120V DC
2.2 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 voltage indicator 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.
Before each use the voltage indicator should be examined for
damage, cracks, cuts or scratches to the housing, cable and prods.
The cable has black outer and contrasting inner insulation, to allow
damage to the cable to be easily identied. If there is any doubt the
voltage indicator should not be used.

4
Make sure the voltage indicator is dry, clean and free from dust,
grease and moisture while in use to avoid the danger from electric
shock due to surface leakage.
Before and after each use, the voltage indicator must be proven
using a suitable proving device or a known good voltage source.
Do not use the voltage indicator if any expected LED’s fail to
illuminate correctly during proving.
Testing for a voltage that exceeds the specied limits of the voltage
indicator may damage the voltage indicator and may expose the
operator to a shock hazard. Always check the voltage indicator’s
specied limits before use.
The specied measurement category means the voltage indicator
will be safe to the user if connected to a voltage up to 1000V to
earth on a CAT II or CAT III installation and 600V to earth on a
CAT IV installation. It does not mean it can be used to test for a
voltage beyond its maximum specied limits.
If using the voltage indicator in falling rain or damp conditions, the
operator must use additional protection to avoid the danger from
electric shock due to surface leakage.
Select appropriate test prods and secure with captive ring nuts. The
L-shaped test prods should be oriented in one of four directions
using the square location feature before it is secured.
When changing or adjusting the prods, ensure that both prods have
been disconnected from any source of power or other equipment.
Always keep your ngers behind the nger guards. Never touch the
exposed metal prod tips.
The different indicating signals of the voltage indicator (including the
ELV limit indication) are not to be used for measuring purposes.

5
The voltage indicator must not be dismantled or modied in any way
by unauthorized persons. The safety of the voltage indicator cannot
be guaranteed under such circumstances and it must not be used.
Cautions
Avoid severe mechanical shock or vibration and extreme
temperature.
If the voltage indicator has been stored or transported in
temperatures outside its normal operating range it should be given
sufcient time to stabilise in the environment where it is to be
used. An acclimatisation time of at least 2 hours is required prior to
operation of the voltage indicator.
2.3 Safety Advice
Depending on the internal impedance of the voltage indicator there
will be a different capability of indicating the presence or absence of
operating voltage in case of the presence of interference phantom
voltage.
A voltage indicator of relatively low internal impedance, compared
to the reference value of 100 kΩ, will not indicate all interference
voltages having an original voltage value above the ELV level.
When in contact with the parts to be tested, the voltage indicator
may discharge temporarily the interference voltage to a level below
the ELV, but it will be back to the original value when the voltage
detector is removed.
When an indication of voltage present does not appear, it is highly
recommended installing earthing equipment before work.
A voltage indicator of relatively high internal impedance, compared
to the reference value of 100 kΩ, may not permit to clearly indicate
the absence of operating voltage in case of the presence of
interference voltage.

6
When an indication of voltage present appears on a part that
is expected to be disconnected from the installation, it is highly
recommended conrming by another means (e.g. use of an
adequate voltage indicator, visual check of the disconnecting point
of the electric circuit, etc.) that there is no operating voltage on the
part to be tested and to conclude that the voltage indicated by the
voltage indicator is an interference voltage.
A voltage indicator declaring two values of internal impedance
has passed a performance test of managing interference voltages
and is (within technical limits) able to distinguish operating voltage
from interference voltage and has a means to directly or indirectly
indicate which type of voltage is present.
3. INTRODUCTION
3.1 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.
3.2 Accessories
•2pc. Straight prod
•1pc. L-shaped prod
•Instructions

7
4. OPERATION
4.1 Control Elements and Connections
MTL10
1
5
3
4
2
MTL20
6
6
1 - Instrument body
2 - LED indicator bands
3 - Straight prod
4 - L shaped prod
5 - Probe handle
6 - Switches (MTL20 only)

8
4.2 Description of LED Indicators
400V band
120V band
230V band
50V band
The magnitude of a voltage is indicated by the illumination of LED’s
in four separate bands around the top of the instrument body.
The nominal voltage thresholds of the indicator LED bands are 50V,
120V, 230V and 400V and are marked next to the relevant band.
The indicator LED bands will illuminate when the magnitude of
the voltage source is at a value approaching or greater than the
corresponding marked voltage. For example if the voltage source is
55V AC rms then only the 50V indicator LED band will illuminate, if
450V AC rms all four indicator LED bands will illuminate.
Note: The individual LED indications are not to be used for
measuring purposes.
4.3 Operating Duty Ratio
The voltage indicator should be operated (ON) for a maximum
period of 30 seconds. This should be followed by a recovery period
(OFF) of 4 minutes.
The operating duty ratio is 8 to 1, so if the voltage indicator is only
ON for 2 seconds then the OFF period need only be 16 seconds.

9
4.4 Proving Check
Before each use the voltage indicator should be examined for
damage, cracks, cuts or scratches to the housing, cable and prods.
The cable has black outer and contrasting inner insulation, to allow
damage to the cable to be easily identied. If there is any doubt the
voltage indicator should not be used.
Before and after use, verify the voltage indicator is functioning
correctly with a proving device (PD440S is recommended), or a
known good voltage source. Do not use the voltage indicator if any
expected LED’s fail to illuminate correctly during proving.
Warning
If the proving device or voltage source exceeds the specied limits
of the voltage indicator the voltage indicator may be damaged and
the operator may be exposed to a shock hazard. Always check the
specication of the proving device or the voltage magnitude of the
voltage source before proceeding with a proving check.
The LED bands that illuminate during proving will depend on the
magnitude of the proving unit output or the voltage source.
For example if the voltage source is 230V AC rms then all LED
bands except the 400V LED band must illuminate. If a PD440 is
used then all LED bands must illuminate.
During this verication emphasis should also be place upon
the exing of the voltage indicators cable along its length, and
particularly at the entry points to the hand held elements, to conrm
that the cable has not been fractured.

10
If using a PD440S for proving, the press button switches on the
MTL20 can also be functionally checked. In this case when both
buttons are pressed simultaneously the 400V LED band will cease
to illuminate, indicating that the added load of the MTL20 has
caused the output voltage of the PD unit to drop, thereby proving
the functionality of the switches and loading circuit.
Any unexpected display should be investigated and the voltage
detector not used until all expected LED’s illuminate.
4.5 Testing for the Presence of Hazardous Live Voltage
Warning
Hold the unit and test leads behind the nger guards in a manner
that will not obscure the voltage band indication LED’s. Never touch
the exposed metal test prods or any part of the instrument forward
of the nger guards while applied to hazardous voltages
While taking all required safety precautions connect the test prods
across the test points where a voltage difference may be present.
The voltage level of any voltage present between the test points will
be indicated by the illumination of the relevant voltage indicator LED
bands.
3.6 Push Button Switches (MTL20 only)
The purpose of the push button switches on the MTL20 is to provide
additional load to the circuit under test where the presence of
interference (phantom) voltage may be suspected (see section 3.7).
Simultaneous depression of both switches (one on the probe handle
and one on the instrument body) introduces a load of approximately
8.8kΩ to the circuit being tested.

11
Note: Interference (phantom) voltages can rise again after the push
buttons are released. If a voltage indication re-appears on the LED
bands while the buttons are not pressed, there may be a hazardous
voltage that must be treated with caution.
4.7 Interference (Phantom) Voltage
It is possible for wiring that is ‘dead’ to indicate the apparent
presence of voltage at power frequency.
If wiring that is live is running in close proximity to the ‘dead’ wiring
being tested, there can be capacitive or inductive coupling between
the two, thereby causing interference (phantom) voltage.
Refer to section 2.3 for safety advice relevant to interference
voltage.

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5. MAINTENANCE
5.1 Probe Replacement
If the test prods become damaged they should be replaced.
Replacement prods are available as spare items:
•AC
•Straight prod (DRUMTL2104)
•L-shaped prod (DRUMTL2105)
Contact your local distributor or contact Martindale Electric on
01923 441717 or email [email protected].
5.2 Periodic Testing
To maintain the integrity of the voltage indicator, Martindale Electric
recommends that it is returned at least once a year to verify physical
integrity, electrical specication and insulation integrity.
Martindale Electric is pleased to offer you this service. Please
contact our Service Department for details.
Email: [email protected] Tel: [phone]
5.3 Cleaning
Warning
To reduce the risk of surface leakage, this instrument must be
kept in a clean condition.
Prior to cleaning, ensure that the instrument is disconnected
from any voltage source.
Wipe the voltage indicator with a cloth soaked with alcohol or mild
non-conductive detergent. Particular attention should be paid to all
areas forward of the nger guards. Do not use abrasives, abrasive
solvents or detergents which can cause damage to the voltage

13
detector. Allow the voltage indicator to thoroughly dry before use.
If contamination is found, clean with a damp soft cloth and if
necessary a mild detergent or alcohol. Do not use abrasives,
abrasive solvents, or detergents which can cause damage to the
unit. If a mild detergent is used, the unit should subsequently
be thoroughly cleaned with a water dampened soft cloth. After
cleaning, dry and allow to remain in a dry environment for 2 hours
before use.
5.4 Repair and Service
There are no serviceable parts in this unit. The MTL10 and MTL20
are sealed units and must not be opened for any reason.
5.5 Storage Conditions
The instrument should be kept in cool, dry conditions and not
subjected to shock, scratching or other damage, prolonged direct
harsh sunlight, extremes of temperature and in such a manner as
to preserve the working life of the unit. It is strongly advised that the
unit is not kept in a tool box where other tools may damage it.

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6. WARRANTY AND LIMITATION OF LIABILITY
This Martindale product is warranted to be free from defects in
material and workmanship under normal use and service. The
warranty period is 2 years and begins on the date of receipt by the
end user. This warranty extends only to the original buyer or end-
user customer, and does not apply to fuses, disposable batteries,
test leads or to any product which, in Martindale’s opinion, has been
misused, altered, neglected, contaminated, or damaged by accident
or abnormal conditions of operation, handling or storage.
Martindale authorised resellers shall extend this warranty on new and
unused products to end-user customers only but have no authority to
extend a greater or different warranty on behalf of Martindale.
Martindale’s warranty obligation is limited, at Martindale’s option, to refund
of the purchase price, free of charge repair, or replacement of a defective
product which is returned to Martindale within the warranty period.
This warranty is the buyer’s sole and exclusive remedy and is in lieu
of all other warranties, expressed or implied, including but not limited
to any implied warranty of merchantability or tness for a particular
purpose. Martindale shall not be liable for any special, indirect,
incidental or consequential damages or losses, including loss of data,
arising from any cause or theory.
Since some jurisdictions do not allow limitation of the term of
an implied warranty, or exclusion or limitation of incidental or
consequential damages, the limitations and exclusions of this
warranty may not apply to every buyer. If any part of any provision
of this warranty is held invalid or unenforceable by a court or other
decision-maker of competent jurisdiction, such holding will not affect
the validity or enforceability of any other provision or other part of that
provision.
Nothing in this statement reduces your statutory rights.

15
CAT Ratings
BS EN61010-1 Installation Categories
(CAT ratings) define the risks from
hazardous transient impulses and
potentially lethal short circuit currents
on the mains supply system based
on where you are working.
Voltage Ratings
Test equipment used for measuring
mains circuits will have a CAT rating
to show where it can be used. Each
category also has a voltage rating
to show the maximum safe phase to
earth system voltage, normally 50V,
100V, 150V, 300V, 600V or 1000V.
Stay safe - Match your test
equipment safety rating to the
installation category.
CAT II: Socket outlets and similar
points of the mains installation.
CAT III: The distribution part of the
building’s mains installation.
CAT IV: The supply side source of
the building’s mains installation.
Testers, leads and accessories
all need safety ratings equivalent
to, or higher than the installation
category and voltage rating for the
location to be safe.
MEASUREMENT CATEGORIES
OVER OR
UNDER
GROUND
PV
ARRAY
*MAIN
ISOLATOR
SWITCH
L1 (L2, L3)
N
PV
ARRAY
DISTRIBUTION
BOARD
LOW-VOLTAGE
SUPPLY SOURCE
CAT III CAT IICAT IV
Tarrif Meter
Service fuse
Circuit Breakers
6
6
Lighting
Generation Meter
Socket Wiring
Socket Outlet
Plug-in Lamps
Electrical Appliances
1
1
2
2
5
5
4
4

Specication
MTL10 & MTL20 Mk2
Test Lamps
Electrical
Maximum working voltage: 500V AC, 750V DC
Nominal voltage threshold indications: 50, 120, 230, 400V AC/DC
Nominal voltage threshold tolerance: Conforms to BS EN 61243-3:2010
Internal impedance at ELV a.c.: 30kΩ (MTL10)
30kΩ / 8.8kΩ (MTL20)
Range detection: Automatic
Response time: <0.1s
Frequency range: DC, 40-65Hz
Switchable load (MTL20 only): approx. 8.8kΩ load
Test current:
MTL10 & MTL20 (switches not operated): <3.5mA at 500V AC rms, 750V DC
MTL20 (switches operated):
approx. 28mA at 230V AC rms, DC
approx. 60mA at 500V AC rms, DC
Duty ratio: 30s ON (operated) / 240s OFF (recovery)

Environmental
Temperature (Operating & Storage): -10°C to 55°C
Humidity (Operating & Storage): ≤ 85% R.H.
Altitude: up to 2000m
Pollution degree: 2
General
Power: from circuit under test
Dimensions: 213(L) x 112(W) x 72(D) mm.
Weight packed:
MTL10 – 320g approx.
MTL20 – 350g approx.
Includes: 2pc. Straight prod, 1pc. L-shaped prod, instructions
Safety
Conforms to BS EN 61243-3:2010 CAT IV 600V
Class II, double insulation.
IP rating: IP64
Probe tips comply with GS38
EMC
Conforms to BS EN 61326-1.
Specication
MTL10 & MTL20 Mk2
Test Lamps

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Due to policy of continuous development, Martindale Electric reserves the right to alter
equipment specification and description outlined in this document without prior notice.
No part of this document shall be deemed to be part of any contract for the equipment
unless specifically referred to as an inclusion within such contract. © 2022 Martindale
Electric Co. Ltd. Registered in England No. 3387451. LITMTL10/20
Ver. C1.1
Martindale Electric Co. Ltd. Metrohm House, 12 Imperial Park,
Imperial Way, Watford WD24 4PP. T: [phone] F: [phone]
www.martindale-electric.co.uk [email protected]