Appendix CTest procedure – road lighting (circuits energised)#

This procedure details the required tests to be conducted for road lighting when main circuit is live.

Refer to AS/NZS 3017 Fig 3.14 for full test sequence, where testing requiring no voltage to be applied has been substituted by obtaining current readings (test sequence d), part 2 following).

Procedure (in order of sequence)#

a)Visual inspection#

1. i.Check for any dangerous vermin/biohazards in the switchboard.
2. ii.Make sure the switchboard door and cabinet are correctly earthed.
3. iii.Make sure the MEN link is available (if applicable).
4. iv.Check all exposed conductors cannot be inadvertently accessed (IP2X).
5. v.Look for mechanically damaged equipment, unsupported parts, and cables in tension.
6. vi.Visually check all earthing conductors are connected to the earth bar.
7. vii.Visually check that neutral conductors are connected to the neutral bar.

b)Earth continuity [no voltage test, but working in vicinity of live parts] (for poles can be omitted using alternative refer test sequence f))#

1. i.Isolate supply and confirm no voltage present on load side of main switch and neutral.
2. ii.Complete the following noting possible risk. Disconnect the main earth and MEN from the neutral link. Disconnection point is the earth bar.
3. iii.Place Ohmmeter between the earth bar of the switchboard and the post of each road light using suitable trailing lead (of suitable length recommended).
4. iv.If photo cell is located on a separate metal structure i.e. traffic signal post, then test earth continuity up to the photo cell.
5. v.Record results (measure the resistance of the trailing lead also).
6. vi.Reconnect the main earth and the MEN.

This test can be replaced by completing Earth Fault Loop Impedance test if traffic conditions do not permit use of a trailing lead

c)Insulation resistance test (via leakage current testing)#

Insulation resistance testing requires the supply to be disconnected; therefore, as per AS/NZS 3019 clause 4.7.4, leakage current test is to be conducted using a leakage current clamp meter.

1. i.Simultaneously measure the current in the active and the neutral conductors under test.
2. ii.If leakage current is greater than 10 mA then further testing is required to determine source.

d)Polarity test#

Test sequence part 1 – Voltage readings#

The following test sequence shall be completed with the supply on.

1. i.Check operation of voltage indicator test unit.
2. ii.Confirm main switch closed.
3. iii.Connect one test lead to known earth.
4. iv.Connect other test lead to terminals (one at a time) of switch.
5. v.With switch ON, measure voltage. Voltage should be 230 – 240 Vac at both terminals.
6. vi.Using the test lead referenced in step iv. make contact with other test lead to active and neutral terminal (one at a time).
7. vii.With switch ON measure voltage. Voltage should be 230 – 240 Vac at active terminal, 0 Vac at neutral terminal.
8. viii.Disconnect test lead from earth.

e)Correct circuit connections#

1. i.Prove that the active, neutral and protective earthing conductors of each circuit are correctly connected so that there is no:
2. short circuit between conductors
3. transposition of conductors that could result in the earthing system and any exposed conductive parts of the electrical installation becoming live
4. interconnection of conductors between different CCTS.

f)Earth Fault Loop Impedance (each light to be tested individually)#

1. i.Confirm light switch is ON.
2. ii.Connect Loop Tester at the road light on each run. Measure EFLI at load side of the switch.
3. iii.Take two sets of readings, about 30 seconds apart.
4. iv.Confirm results are same – otherwise test again.
5. v.Record the type and size of the protective device.

g)Infrared thermal imaging#

1. i.In accordance with AS/NZS 3019 Clause 5.8, equipment is to operate under normal operating loads for at least 30 minutes.
2. ii.Measure the temperature of the equipment components using the infrared thermal imaging equipment.
3. iii.Determine if any equipment is affected by excessive rise in temperature. If high temperature values are measured, rectify installation. Retest equipment components including use of infrared thermal imaging equipment.

Drawings from the original pages

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