Metrel Instaltest 3017: A "must-have" for electricians & contractors

Supplier: Emona Instruments By: Leo Simpson
29 May, 2014

Did you know that it's now mandatory for electricians to provide a written safety test report when they install new wiring or do repairs to your home, office or factory?

The Metrel Instaltest 3017 does all the tests specified in the Australian/New Zealand AS:NZS3017 standard.
It also provides a step-by-step guide for electricians when they are doing visual checks as well as the electrical tests.

Providing a comprehensive report after an electrician has made repairs or changes to a home or building is a fairly onerous requirement. Not only does the electrician have do the actual wiring or repairs but they now also needs to provide a report, termed the Electrical Safety Certificate, as specified by the relevant organisation in each state. They need to give a copy of the report to the customer and they need to keep a copy for their own records.

Preparing this certificate is no simple task, as it must indicate that all required visual checks have been made and the electrical tests done, including the actual test readings where appropriate. All told, this can add up to quite a lot of work and it means that the electrician must be well organised to do the tests and then create the report for the customer, often after hours when all the "proper work" has been done.

To indicate just how much work can be involved, consider a typical large home these days with multiple power and light circuits. If it is a complete wiring job, each power point and light socket needs to be tested and noted on the report.

Enter the Metrel Instaltest 3017. It has been designed to take the drudgery and much of the paper work out of the process. As well as compliance testing, the Instaltest 3017 can be used for trouble-shooting and also as a cable locator (with an optional kit).

The instrument itself is quite compact and measures about 230mm wide, 103mm high and 117mm deep. It has an LCD screen flanked by membrane switches on the front panel. At the top of the case is connector panel with a sliding door which allows access to a USB socket and a PS2 socket for serial communication to a computer and a DC socket for charging the internal batteries.

The LCD can be illuminated for viewing in poor lighting conditions.

Along with the AS3017 Instaltest instrument itself, the package contains a comprehensive set of test leads and add-ons to cover all tests required under AS/NZS3017. These include tests for voltage and frequency, insulation resistance, fault loop impedance, RCDs and phase rotation. Optional kits also allow earth resistance metering and cable locator/circuit tracing. Not shown here is the comprehensive instruction manual, also included.

For visual checks of wiring, switchboards and so on, the Instaltest 3017 has a number of inbuilt procedures and as you step through them, you can tick the boxes as you go. There is no need to have separate paperwork. Then, you can do the actual tests such as electrical continuity and resistance, insulation resistance, polarity, correct connec- tions, fault loop and RCD tests. Most of these tests, with the exception of polarity (testing whether Active is at 240VAC and Neutral is 0V with respect to earth) are done with no power in the system.
In order that the Instaltest can verify that the Active, Neu- tral and Earth connections in GPO (general purpose output, power point) are correct, a test box must be connected to the circuit at switchboard, with  power  disconnected  via the circuit breaker. The test box connects a 1Ω  resistor between Active & Earth and 5Ω resistor between  Neutral  and Earth. The Instaltest can then check for correct polarity  and  earth  continuity.
Insulation tests are done at 1000V (internally generated). The test shows the insulation resistance (up to 30 megohms) and the test voltage. The instrument can also be used to test the insulation resistance of heating elements (in hot water tanks etc).

The Instaltest 3017 has a very good procedure for check- ing RCDs (residual current devices) and checks each one for six parameters. Having nominated the RCD type (ie, 10mA, 30mA, 100mA etc), the Instaltest tests at half, one and five times the rated current at normal and reverse polarity (180 degrees) and gives the trip times in milliseconds. Each time it trips the RCD, you need to reset it whereupon the Instaltest will do the next step, for all six test.

As each test is completed, you press the F2 button to commit the data to memory and then continuing through until all tests are done. After the job is complete and the electrician is able to do normal paperwork tasks such as invoicing, the Instaltest is connected via the USB or se- rial port to a computer and all the data downloaded to that reports can be compiled for the clients. The printed reports can then be presented to the customer, together with the invoice.

Using an optional transmitter box, the Instaltest can also be used for cable tracing in complex power systems.

All told, the Metrel Instaltest 3017 should be the an- swer to an electrician or contractor’s prayers, providing fully documented reports to cater for all repairs and new installations.