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Kewtech KT300 Digital Insulation Continuity Tester

NEW The Kewtech KT300 Digital Insulation Continuity Tester, using the latest in technology, provides a slick way to go 18th edition

Important Calibration Information

This instrument comes with a manufacturers calibration certificate.
Please see 'Calibration Options' in the description for more details.

Next Day Delivery (subject to availability)

£316.67 exc. VAT £380.00 inc. VAT £513.60 inc. VAT
  • Audible
  • Breakdown voltage
  • Buzzer facility
  • Hands Free function
  • Insulation test at 50V, 100V 250V, 500V & 1000V
  • Test lead null facility
  • Voltage present LED
  • FreeDelivery
  • 30DayMoneyBack
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  • Description
  • Features & Specification
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Kewtech KT300 Digital Insulation Continuity Tester

Fully featured single function tester that fits your hand - a great way to go 18th edition testing

Kewtech's long awaited revision of the highly popular KT3x series of single-function testers.
A suite of three testers for those who prefer to do their testing with separate instruments as opposed to the multifunction tester scenario. Gone is the now very dated old square box and analogue display, in comes a new ergonomic case design with a fully digital display. Boasting a host of new features and enhancements over the predecessors this set of testers will surely find favour with many engineers and electricians who prefer this style of ownership.

*Important Calibration Information:

This instrument comes complete with the manufacturers calibration certificate. Please be aware that these certificates are generic and may also be time lapsed.
If you would prefer a personalised full traceable calibration certificate applied to the equipment before dispatch, then please select this option from the drop-down menu above, an additional calibration charge will apply.

Kewtech KT300 Comes Supplied With:

  • ACC020 two wire test lead set 
  • Carry Case 
  • Manual 
  • Batteries 
  • Calibration certificate 

Key Features:

  • Insulation test at 50V, 100V 250V, 500V & 1000V 
  • Continuity test with audible tone 
  • Test lead null facility 
  • Buzzer mode 
  • Hands free function 
  • Breakdown voltage 
  • Voltage present LED 
  • Auto power off 

Makes a great 18th Edition kit along with the KT400 (Loop Impedance Tester) and the KT500 (RCD Tester).

ISSWWW and Kewtech

One of our longest standing manufacturer partnerships and a brand that sells well day in day out for solid dependability and innovation at the price point.

Kewtech manufacture innovative, accurate and reliable test equipment that enables UK electrical contractors to undertake their testing obligations quickly and efficiently. 

A product with the “Kewtech” brand has been specifically designed for the UK market by a team with many years of industry experience. We pride ourselves on developing and manufacturing products that have real benefit to the industry.

Kewtech have consistently introduced industry firsts, like our Lightmate testing adaptors, the Pat Adaptor, the MFT with PAT testing plus download and our award winning RB1 Replacement Lamp. Our 18th Edition multifunction testers lead the way in ease of use, loop accuracy and repeatability of reading.


Kewtech KT300 Digital Insulation/ Continuity Tester Technical Specifications

Continuity Test Range Accuracy
Range Tolerance (@20ºc)
0.00 to 9.99 Ω + (3% + 2 digits)
10.0 to 99.9 Ω + (3% + 2 digits)
100 to 19.99 kΩ + (3% + 2 digits)
Open circuit Voltage >4V, <10V
Zero offset adjust (test lead null) 5 Ω
Typical test time (2 Ω) >2 seconds
Hazard Warning LED >25V
Run Leakage
Test Voltage Ranges (Auto Range) Tolerance (@ 20°C)
50 V 0.01 to 9.99 MΩ ± (6% + 2 digits)
10.0 to 49.9 MΩ ± (6% + 2 digits)
100 V 0.01 to 999 MΩ ± (6% + 2 digits)
10.0 to 99.9 MΩ ± (6% + 2 digits)
250 V 0.01 to 9.99 MΩ ± (3% + 1 digits)
10.0 to 99.9 MΩ ± (3% + 1 digits)
100 to 199 MΩ ± (6% + 1 digits)
500 V 0.01 to 9.99 MΩ ± (3% + 1 digits)
10.0 to 99.9 MΩ ± (3% + 1 digits)
100 to 199 MΩ ± (3% + 1 digits)
200 to 499 MΩ ± (6% + 1 digits)
1000 V 0.01 to 9.99 MΩ ± (3% + 1 digits)
10.0 to 99.9 MΩ ± (3% + 1 digits)
100 to 399 MΩ ± (3% + 1 digits)
400 to 999 MΩ ± (6% + 1 digits)
Insualtion Output Voltage 
Voltage Load Output Current Tolerance
50 V 50 kΩ 1 mA -0% +20%
100 V 100 kΩ 1 mA -0% +20%
250 V 250 kΩ 1 mA -10% +20%
500 V 500 kΩ 1 mA -10% +20%
1000 V 1 MΩ 1 mA -10% +20%
Short circuit current (into 2k Ω) < 2 mA
Typical Test Time (10 MΩ) < 2 seconds
General Specifications 
Power supply 4 x AA LR6 Batteries
Battery life 50 hours
Overvoltage category CAT III 500V
Operating temperature 0 - 40ºC
Storage temperature -10 to 60ºC
Operating humidity 80% @ 31ºC to 50% @ 40ºC
Safety compliance BSEN 61010-2-030:2010
EMC compliance BSEN 61326-2-2:2013
Performance standard BSEN 61557-1:2007
BSEN 61557-2:2007
BSEN 61557-4:2007
Probes GS38 compliant
Dimension (mm) 180mm x 85mm x 50mm
Weight (g) Approximately 450g
There are no files associated with this product. For more information please call 0800 0224 060

Orders requiring calibration 

Whilst we take the greatest care to get all orders dispatched and delivered to you in the stated time frame, orders received PM and requiring
calibration may on occasion miss dispatch that day, according to the complexity of the calibration. Be assured they will ship on the next dispatch
this in most cases should not add more than 24 hours to your delivery.

Bank/Public Holidays

Predicted delivery times are based on regular trading days Monday to Friday. Public holidays, bank holidays and weekends are outside the usual scope 
of our dispatch and subject to activities/holidays of our carriers and therefore may incur additional days lead time to your order.

*UK Mainland (Temporarily revised June 2020)

Please note that regrettably, we have had to realign our delivery service options to those available from our carriers.
During the current situation surrounding the effects of the Coronavirus pandemic, logistics from every company are under immense pressure to deliver goods on time.
We have taken the decision to temporarily limit our services rather than let our customers down.
We hope you will understand our position on this and we apologise unreservedly for the inconvenience we know this will cause.
We look forward to restoring our full delivery service schedule just as soon as we are able.

Standard FREE 1-2 Day Courier Delivery – UK Mainland only - Zones A & B

Included in the price for all orders over £75.00 (exc vat). Sent using express courier, delivered within 1-2 working days from the date of your order, subject to availability.


Next Day Anytime Delivery (Excluding Saturday & Sunday) – UK Mainland only - Zones A & B
Sent by express courier, delivered next day (excluding weekends) from the date of your order, subject to availability.


Orders must be placed before 3:00pm for a qualifying next day delivery and a telephone number supplied, subject to availability.

New Postage Map Sept 2018>

Delivery Surcharges

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

  • Zones A & B  - Mainland delivery rates apply. 
  • Zone C - Scottish Highlands (Charges are calculated at the checkout).
  • Zone D - Outer Hebrides, Orkney Isles, Shetland Isles, Isle of Man, Scilly Isles, and Channel Islands (Charges are calculated at the checkout).
  • Zone E - Northern Ireland (Charges are calculated at the checkout).
  • Zone F - Republic of Ireland (Charges are calculated at the checkout).

Offshore Services

All offshore deliveries are a 2 day service as standard. This includes Channel Islands, Northern & Southern Ireland, Scottish Islands, Isle of Man and the Scilly Isles.

International Delivery

International delivery charges are automatically added to your order at the checkout. For any questions regarding international deliveries please contact us at


All export inquiries should be directed to the export division before placement of order.

If no shipping option is available to your selected country please call us FREE on 0800 0224 060 to purchase your items.
All stated prices are subject to VAT at the current rate where applicable E&OA