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Megger LTW315

The Megger LTW range of wire non-tripping loop testers have stood the test of time and are a staple for many electrical engineers

Next Day Delivery (subject to availability)

including VAT @ 20%
Regular Price:
  • Manufacturer Certificate Included
  • 2 wire non-tripping loop test
  • 0.01 ohm resolution
  • Non Trip Testing
  • FreeDelivery
  • 30DayMoneyBack
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Megger LTW315 Earth Loop Tester

The entry-level tester in Megger's earth loop tester range, the LTW315 is used for carrying out 2 wire loop impedance measurements on phase to earth or phase to neutral.

Guaranteed not to trip working RCDs of more than 30mA thanks to a non-trip loop test and compatible with both three and single phase systems, this tester makes performing measurements easier by requiring the use of only 2 test leads in order to carry out measurement procedures. When there is no risk of tripping an RCD it is also possible to use high current loop testing mode.

When carrying out no-trip testing procedures the LTW315 constantly evaluates the level of noise detected on circuitry to ensure that the accuracy of results is not modified by the presence of electrical noise.

The Megger LTW315 is part of the LTW range of earth loop testers. The following table outlines the difference between each of the available models in this series.


Megger LTW315 Comes Supplied With:

  • Megger LTW315 Earth Loop Tester
  • BS1363 to 3 x 4mm Socket Leadset
  • 2 Wire Leadset with Croc Clips
  • Shuko Plug Test Lead – EU-SC
  • AU/NZ Plug Test Lead – EU-AU
  • Hard Carry Case
  • User CD

Key Features:

  • 2-wire loop testing procedures on phase to earth and phase to neutral
  • Guaranteed to not trip out RCDs thanks to non-trip loop testing
  • Noise detection filters out electrical noise that can create erratic readings
  • Resolution down to 0.01Ω
  • Portable lightweight instrument with tough carrying case encasing the tester
  • AUTO start function starts testing as soon as the leads are connected
  • PFC display up to 20kA

Megger LTW Series Selection Chart

 Function   LTW315   LTW325   LTW335   LTW425 
 2-Wire Non Tripping Loop Testing  X X X X
2-Wire Fast Test (High Current) X X X X
110V to 280V Applications X X X X
50V to 440V Applications   X X X
Phase to Phase Testing   X X X
20KA PFC Range X X X X
40KA PFC Range       X
0.01Ω Resolution X X X X
0.001Ω Resolution       X
AUTO Noise Detection X X X X
AUTO Start Loop Test X X X X
Voltage Measurements X X X X
Frequency Measurements X X X X
Max Zs Display   X X X
R2+R2 Display   X X X
Backlit Display (White Light) X X X X
Built-In Front Cover (Foldaway) X X X X
IP54 Weatherproof Case X X X X
Accepts Rechargeable Batteries X X X X
Test Result Storage     X  
Downloadable     X  


Megger LTW315 Loop Tester
General Accuracy
All accuracy statements are based on:  
Ambient Temperature 23° ±2°C
Nominal Voltage Source 230V a.c ±1%
Voltage Measurements
(ac only) 50V to 440V
Accuracy ±2% ±1V
Frequency Measurements
Range  25Hz to 99.99Hz 
Accuracy ±0.1Hz
 A warning will be shown if applied voltage exceeds 440V.  
Damage will occur if applied voltage exceeds 600V rms
Loop Testing Accuracy
±5% ±0.03Ω @230V a.c
±10% ±0.03Ω @100V a.c and 280V
No Trip Loop and High Current Loop Test
Source Voltage  100V to 280V (49Hz to 50.1Hz) 
Display Range 0.01 to 2000Ω
Accuracy ±5% ± 0.03Ω
No Trip Loop Test Nominal Current  15ma (at nominal 230V a.c supply) 
High Current Loop Test 4A (at nominal 230V a.c supply)
Operational Range 0.30 to 1000Ω
Prospective Fault Current (PFC)
Prospective Fault Current  =Measured Source Voltage/Loop Resistance 
Maximum Range No Trip Mode: 20KA
Accuracy is derived from loop test and voltage measurement

IEC 61010
Designed to IEC61010-1
Designed for 300 volts to Earth Category IV
with phase to phase voltages to 440V.
Fuse protected to 600 volts rms AC


Complies with the following parts of EN61577:  
Electrical Safety in Low Voltage Systems up to
1000V ac and 1500V dc - Equipment for testing,
measuring or monitoring of protective measures:
Part 1: General Requirements
Part 3 - Loop Resistance

E.M.C In accordance with IEC61326-1
Power Supply
Battery 8 x 1.5V Cells IEC LR6 Type (AA Alkaline)
Rechargeable 8 x 1.2V NiCd or NIMH Cells
Battery Life 2000 consecutive tests
Weight 1000g ±10% excluding test leads
Dimensions 203 x 148 x 78mm

Standard Delivery 3-5 Day Delivery – UK
£2.95 for all all orders under £40.00 (exld vat). Sent by Royal Mail Tracked, delivered/posted within 3-5 working days from the date of your order, subject to availability.

Standard Free Delivery 3-5 Day Delivery – UK Mainland only - Zone A & B
Included in the price for all orders over £40.00 (exld vat). Sent using FedEx, delivered within 3-5 working days from the date of your order, subject to availability.

Express DPD Delivery 1-2 Day Delivery – UK Mainland only - Zone A & B
£4.50 select at the checkout. Sent using DPD on their Award Winning “Predict” Service with these great key benefits:

  • You are given a one hour delivery window. (no more waiting in all day for your parcel)
  • You are notified by text or e-mail on your parcels progress.
  • Change of plan? You can easily use the text or e-mail to rearrange your delivery.
  • Notifications on your parcel up to 15 minutes before delivery.

Orders must be placed before 3pm for next day delivery and a mobile number supplied, subject to availability.

Next Day Delivery – UK Mainland only - Zone A & B
£8.00 select at the checkout. Sent using FedEx, orders must be placed before 3pm for next day delivery, subject to availability.

Saturday Pre 12am - UK Mainland only - Zone A & B
£15.00 select at the checkout. Sent using FedEx, orders must be placed before 3pm for Saturday delivery.

Delivery Surcharges
Because of the high cost of carriage we need to apply a surcharge on all deliveries made in the following regions: 

  • Scotland, Isle of Wight & Isles of Scilly - £6.00  
  • Scottish Highlands and Northern Ireland - £12.00  Zone C
  • Scottish Islands, Isle of Man and Channel Islands - £14.00  Zone D
  • Southern Island - £15.00  Zone E


 International delivery

International delivery charges are automatically added to your order at the checkout; you can also use the guide below for a guide on prices. For any questions regarding international deliveries please contact us at

 Zone 1:

  • France, Germany, Belgium, Netherlands, Luxembourg. £20.00 per parcel

Zone 2:

  • Austria, Denmark. £22.00 per parcel
  • Liechtenstein, Switzerland £47.00 per parcel (added cost for custom clearance surcharge)

Zone 3:

  • Czech Republic, Italy, Slovakia, Spain. £28.00 per parcel

Zone 4:

  • Estonia, Finland, Hungary, Poland, Portugal, Slovenia, Sweden. £50.00 per parcel

Zone 5:

  • Bulgaria, Croatia, Greece (incl islands) Latvia, Lithuania, Romania. £60.00 per parcel

Bosnia-Herzegovina, Iceland, Norway, Serbia. £85.00 per (added cost for custom clearance surcharge)

If no shipping option is available to your selected country.  Please call us on +44 (0) 1603 406 148 to purchase your items.