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ELI Testing

SJG provides ELI Testing throughout Warwickshire - and beyond

What is ELI Testing?
ELI testing means Earth Loop Impedance Testing. It is, basically, electrical safety testing of 240v socket outlets.

The Tests
SJG makes accurate measurements of Wiring, Earth Loop Impedance and Phase Neutral Impedance quickly and easily.  The testing employs patented 'T Safe' non-trip technology to avoid tripping in-circuit Residual Current Devices (RCDs).
The test is a comprehensive check of the wiring to obtain an Earth Loop Impedance and Phase Neutral Impedance result displayed to 2 decimal places, in accordance with the requirements of BS 7671 17th Edition.

The package of tests made on each outlet allows for a simple pass or fail scenario. Sockets passing are indicated by a simple pass sticker whilst failures are rendered unusable and a fault report is produced.

If the test detects a fault condition in the wiring under test, or the supply voltage is less than 198V (<198V) or greater than 264V (>264V), or the Earth
Loop Impedance is greater than 3000Ω(>3000Ω) or Phase Neutral Impedance is greater than 3000Ω a failure will be recorded

Nominal Voltage Rating:220 - 240 V
Voltage Range for Wiring Error Detection:30 - 275 V
Open Loop indication: If Open PE or PN Loop is detected, no Impedance Measurement takes place
Voltage Range for Impedance Measurement:198 - 264 V
Frequency:50 Hz
Loop Impedance Ranges:0- 8.99Ω, 9.0- 89.9Ω,90- 899Ω,900-1699Ω,1700-3000Ω
Phase Earth Loop Impedance Accuracy:
0 - 8.99Ω, � 4% � 0.05Ω*
9.0 - 89.9Ω, � 5% � 0.5Ω*
90 - 899Ω, � 5% � 5Ω*
900 - 1699Ω � 5% � 30Ω*
1700 - 3000Ωindicative
Phase Neutral Loop Impedance Accuracy:
.0 - 8.99Ω, � 4% � 0.05Ω*
9.0 - 89.9Ω, � 5% � 0.5Ω*
90 - 899Ω, � 5% � 5Ω*
900 - 1699Ω � 5% � 30Ω *
1700 - 3000Ωindicative
Voltage Accuracy: � 4 %
Frequency Accuracy: � 4 %
Temperature Range: -10� to 40� C at max 80 % Relative Humidity (Non-Condensing)
Power consumption: < 1.6 W
Overvoltage category: Cat III/ 300V

RCD in the Circuit Under Test
The test should not trip RCD's during the testing of wiring with in-circuit RCD's.
Note, however, that many modern products have a constant low level of earth leakage, to ensure that noise and stored charge is dissipated, for example, 3mA earth leakage is typical for a desk-top computer.
Note, also, that a 30mA RCD is guaranteed to trip at 30mA earth leakage, should not trip at 15mA, but is very likely to trip with earth leakage currents above 22mA.

Possible Measurement Errors of Earth Loop Impedance
Where supply circuits under test have highly inductive or capacitive components distributed on that circuit (such as mains filters), or there is an excessive amount of mains disturbance present (e.g. motors running, rain shorting exposed wires, or a generator with high inductance supplying power, etc), it is possible the Phase Neutral and Earth Loop Impedance measurement could be adversely affected.
The report PN CIRCUIT NOISE is used to indicate noise on the Phase Neutral wires. The report PE CIRCUIT NOISE is used to indicate noise on the Phase Earth wires. If the noise levels on Phase Earth are not adversely too high, an estimated Phase Earth Impedance measurement is used together with a circuit noise warning.

PAT Testing

sjg provides Pat Testing throughout Warwickshire - and beyond

Fast, Efficient Testing of 110v, 230v and IT equipment

Compatible with latest IEE Code of Practice

Fully CERTIFIED & DOCUMENTED testing of all 'portable' mains equipment

Regular Annual or ad-hoc testing

Out of hours testing at NO EXTRA CHARGE

What is PAT Testing?
Portable Appliance Testing (PAT) is an important part of a company's or individual's Statutory responsibility to health and safety.
This is done using a series of specialized testing procedures on all 'portable' appliances where the items are inspected and tested with a special 110v/240v testing device.
This ensures the equipment is in a safe condition for use.

The list of Portable Appliances is extensive. Typically, if the appliance [110v & 240v] can be unplugged from its power source then it will need a PAT Test.

What is Tested?
1. Plugs & Adapters are checked for compliance, damage and correct fitting.
2. Cables & leads are checked for wear and tear; heat damage; cuts and abrasions
3. The appliance housing is checked for compliance and damage: cracks, dents and corrosion .
4. An Earth bond test is conducted to ensure earthing of appliance meets acceptable standards.
5. An Insulation test is conducted to ensure the insulation protecting the conductors is valid
6. An Earth Leakage test measures leakage current to earth while the appliance is operating
7. A Function & Load test ensures the appliance is operational within stated parameters.

Each appliance that passes the inspection is labelled with an id number, retest date and engineer's initials. A certificate with test values is produced for each item and an inventory spreadsheet details all items.

SJG PAT Testing

Value added services available from SJG:

Network Infrastructure: Supply, installation & maintenance of voice & data networks; cat 5, 6 fibre.
Telephone systems: Supply, installation & maintenance of telephone systems inc. VoIP
Specialised testing Datacomms: Fibre, ISDN [PRI, DASS , DPNSS & BRI]
Specialised testing Electrical: PAT, ELI, Distribution
CCTV: Supply, installation & maintenance of CCTV
Door Entry & Access Systems: Supply, installation & maintenance of multiple integrated access control systems
Nurse Call Systems: Supply, installation & maintenance of systems for healthcare sectors


Areas Covered

Banbury, Gaydon, Leamington Spa, Rugby, Southam, Warwick



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