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Martindale PD690S Proving Unit 690V AC

NEW The Martindale PD690S proving unit is fast and easy to use, instantly supplying the full test voltage for both high and low impedance voltage indicators, test lamps and meters.

Next Day Delivery (subject to availability)

£80.45 exc. VAT £96.54 inc. VAT £118.80 inc. VAT
  • Colour Coded Voltage Output
  • Durable Overmoulded Boot
  • Low Battery Indicator
  • Magnetic Hanger Included
  • LED Indication
  • 690V Proving Unit
  • Batteries Included
  • FreeDelivery
  • 30DayMoneyBack
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  • Description
  • Features & Specification
  • Resources
  • Delivery (updated)

Martindale PD690S Proving Unit 690V AC

Safe electrical working requires the use of a voltage indicator that has been proven with a suitable proving device before and after use to ensure the instrument is working correctly in accordance with the Electricity at Work Regulations.
With all the benefits of the industry standard Martindale PD440 and PD690 proving units, the new S models come in an overmoulded low profile case with magnetic hanger. They are fast and easy to use, instantly supplying the full test voltage for both high and low impedance voltage indicators, test lamps and meters.

The SX Series have a unique CALCHECK feature making it easy to verify the insulation and low resistance ranges on 18th Edition multifunction testers, wherever you are working. In addition, the new SX models have stepped voltage LEDs with thresholds matched to most voltage indicators and two pole testers.

Martindale PD690S Comes Supplied With:

  • MG3 magnetic hanger
  • 6 x 1.5V AA alkaline batteries
  • Instruction manual

Key Features:

  • Ideal for proving low and high impedance voltage indicators, test lamps and two pole testers
  • Includes MG3 high strength magnetic hanger
  • Colour coded for voltage output (440V and 690V)
  • Tough overmoulded low profile design
  • Long battery life with low battery indicator and auto power off

Additional features PD440SX and PD690SX

  • Unqiue CALCHECK feature for verifying insulation and low resistance ranges of installation testers
  • Stepped voltage output matched to two pole tester thresholds


Which Martindale Proving Unit is right for me?

Selector Chart


ISSWWW and Martindale Electric

Founded in 1928 and also owns Edgcumbe Instruments Metrohm® products, as well as the John Drummond Engineers range of test lamps. They are a British owned company, based in Watford, just 5 minutes from junction 5 of the M1.

Their product range helps electricians and maintenance engineers carry out portable appliance testing, check fixed wiring for 17th Edition and Part P testing, safely prove dead, and measure everything from light and sound levels to microwave leakage and power consumption.We are proud to be able to offer Martindale's products and services and have done so for many years.

Martindale PD690S Proving Unit Specification
Output voltage 690V nominal
Output frequency 50Hz nominal
Output loading See datasheet
Temperature (Operating & Storage) -10°C to 40°C
Humidity (Operating & Storage) max. 70% R.H.
Altitude up to 2000m
Pollution Degree 2
Power 6 x 1.5V, AA alkaline batteries (IEC LR6, NEDA 15A)
Dimensions 150 x 80 x 35mm
Weight 350g approx. with batteries

Delivery Notices (Updated March 29th 2021)

During the current situation surrounding the effects of the Coronavirus pandemic, logistics from every company are under immense pressure to deliver goods on time.
Coupled with manufacturers on reduced output due to more stringent working practices and a global shortage of component parts to supply UK manufacturing, we have taken the decision to 
temporarily limit our services rather than let our customers down amid these unprecedented circumstances.
We hope you will understand our position on this and we apologize unreservedly for the inconvenience we know it will cause.

Please note that ALL orders placed before 3:00pm are shipped same-day (subject to stock and any additional services required).
The stated transport times above have some scope for adjustment built-in for the Covid-19 situation. Carriers themselves also have their own extended workload and limitations at this time which are unfortunately beyond our control.

Easter 2021

Easter is always a busy time for suppliers and distributors alike, please bear in mind that we will be away from the office from 17:00 Thursday 1st - 08:00 Tuesday 6th April.
This will likely further impact expected lead times on goods arriving and leaving our premises, we advise you to place your order in good time to negate delays as far as possible.
We apologise for the added disruption that this period is likely to bring.

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 (Revised March 2021)

Service  Price 
Standard FREE 2-3 Day Courier Delivery – UK Mainland only - Zones A & B - Order value OVER £75.00 ex VAT - Order by 3:0pm FREE
Standard FREE 2-3 Day Courier Delivery – UK Mainland only - Zones A & B - Order value UNDER £75.00 ex VAT - Order by 3:0pm £4.75
Next WORKING Day (excludes Saturdays, Sundays and public holidays)  – UK Mainland only - Zones A & B  - ANY order value - Order by 3:0pm      £7.75
Saturday ANYTIME Delivery - Order by 3:0pm £9.95

New Postage Map Sept 2018>

Delivery Surcharges

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

  • 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 3-4 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.