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Seaward Powertest 1557 Multifunction Tester

FREE Gift Seaward Powertest 1557 Promotion. A cost effective multifunction tester

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)

£299.00 excluding VAT £358.80 including VAT @ 20% Regular Price: £992.40
  • Fully 18th Edition Compliant
  • Manufacturers Calibration Certificate
  • Auto RCD
  • Backlit LCD Display
  • Non Trip Loop Testing
  • FreeDelivery
  • 30DayMoneyBack
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  • Description
  • Features & Specification
  • Resources
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Free Gifts

This instrument comes complete with your choice of free gift from the drop-down menu above. Choose from a quality set of 3-wire silicone test leads with croc clips, a calibration voucher for next year or a 50m R2 wander lead. How about any one of the IET Guidance Notes, or a Fluke T90 two-pole tester? 
Whatever you choose you can be sure you're getting a fantastic deal at Instrument Sales & Service.

The PowerTest 1557 multifunction installation tester

The PowerTest 1557 is a multi function installation tester with integral probe, allowing the instrument to be held and the results to be read at the same time.

The PowerTest 1557 is also very fast, performing earth loop, line loop, PFC and PSC tests with one press of a button in under 5 seconds. It's lightweight, handheld and battery powered.

Thanks to a clever bit of design, Seaward have included a cordless probe for use with the tester, meaning you can hold the tester and see the results at the same time. Weighing in at a mere 900 grams, it’s light too. And it can do any test that you require at the turn of a knob, including Earth Continuity, Insulation (100v, 250v, 500v), Non-trip Loop Impedance, Line Impedance, RCD trip line, RCD trip current and voltage / frequency measurements.

*Calibration Options:

This instrument comes complete with the manufacturers dated 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.

Limited Edition package includes:


ISSWWW and Seaward

Established over 30 years ago, Seaward Electronic based in Co. Durham, England is the market leader in the field of electrical safety test instrumentation.

The company provides total test solutions to enable companies and organisations to comply with the demands of all types of electrical safety legislation including portable appliance testing, installation, medical, and machinery testing.

Seaward is renowned for its commitment to continuous product development, innovation, and is the global market leaders in portable appliance test instruments (PATS) and associated accessories such as PAT software. ISSWWW have worked with Seaward throughout our trading history and enjoy mutual support and continued development with them.


Earth Continuity

Test Current >200mA
Display Range 0.00ohms - 199ohms
Resolution 0.01ohms max
Test Lead Compensation: 0.00ohms - 10.00ohms
Live Circuit Detection Test inhibit if >30V detected

Insulation Resistance

Test Voltage 100V, 250V, 500V
Display Range 0.05Mohms - 199Mohms
Resolution 0.01Mohms maximum
Live Circuit Detection Test  inhibit if >30V detected

Loop/Line Impedance

Supply Voltage 195 - 253V/440V, 45Hz - 65Hz
Test Current 15mA (non tripping for RCD protected circuits)
Display Range 0.01ohms - 2000ohms
Resolution 0.01ohms maximum
Loop Impedance Phase to Earth
Line Impedance Phase to Neutral/Phase to Phase
PFC/PSC Range 0 - 26kA


RCD Trip Time

Supply Voltage 195 - 253V, 45 - 65Hz
Test Currents 10, 30, 100, 300, 500mA
Trip Time Ranges 0ms - 2000ms at ½IDn
0ms - 300ms at IDn general
There are no files associated with this product. For more information please call 0800 0224 060

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

Standard 1-2 Day Express Courier Delivery – UK Mainland only - Zones A & B
£4.50 for all all orders under £40.00 (exc vat). Sent by express courier, delivered within 1-2 working days from the date of your order, subject to availability.

Express Courier 1-2 Day Delivery – UK Mainland only - Zones A & B
£4.50 select at the checkout. Sent using express courier.

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

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

Orders must be placed before 3pm for next day delivery and a telephone number supplied, subject to availability.
Please note that 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 therefore may incure additional days lead time to your order.

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 late afternoon 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 you delivery.

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. 
  • Zone D - Outer Hebrides, Orkney Isles, Shetland Isles, Isle of Man, Scilly Isles, and Channel Islands.
  • Zone E - Northern Ireland
  • Zone F - Republic of Ireland

New Postage Map Sept 2018> 

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

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