insulation materials and on the way in which they are applied, but also on the ambient temperature and the relative humidity which shall be recorded at the time of the test.
14.3 Earth continuity
14.3.1 Tests should be made to verify that all earth continuity conductors and earthing leads are connected to the frame of apparatus and to the hull of metal ships or the main earth conductor bar of ships with non-metallic hulls and that socket-outlet earthing terminals are connected to earth. This should also apply where apparatus is bonded directly to the hull.
The earthing arrangements of some control, instrumentation and/or intrinsically safe systems may differ from the normal power earth arrangements and should be given special consideration, e.g. low voltage/low current test equipment.
14.3.2 Where metal-sheathed cables are used, whether armoured or not, tests should be made to verify that all metallic envelopes are electrically continuous throughout their length and are earthed as required, or as may be required for particular arrangements such as when they form part of a control, instrument or intrinsically safe system.
14.3.3 Where earthed systems are used, it should be verified that：
(i) Single-pole control devices and fuses are connected in the live conductor only
(ii) Wiring has been connected correctly to plugs and sockets.
(iii) The outer contacts of Edison screw-type lampholders are connected to the earthed conductor.
14.4 Performance Tests
14.4.1 All switchgear should be loaded as nearly as practicable to its working load in order to demonstrate that no overheating takes place due to faulty connections or incorrect rating.
Infra-red photometry techniques may be employed to assist with this assessment. The measurement of the resistance of joints and contacts by bolt drop methods with the injection of high current from a low voltage source is also recommended. Records should be taken of the readings for subsequent reference.
These techniques may be used at the initial examination and for periodic inspections.
Switches and circuit-breakers should be operated on load and the satisfactory operation of all interlocks is to be demonstrated.
Prior to commencing tests of protective devices, their size, type and ratings should be checked against the design. The operation of protective relays and devices should be effectively demonstrated, which may be by the use of suitable injection testing techniques. Direct acting overcurrent relays can only be tested by primary injection methods but secondary injection may be acceptable elsewhere when the associated current transformers and circuitry should also be tested.
14.4.1 All generator sets should be run over a sufficient range of load, including full rated load, or as near as is practicable to full rated load, and for a duration sufficient to demonstrate that commutation, electrical characteristics, governing, range of excitation control, phase rotation, lubrication and absence of excessive vibration are satisfactory.
If sets are intended to operate in parallel, they should be tested over a range of loads to demonstrate their compliance with the specified requirements.
The voltage and speed regulation when a specified load is suddenly thrown on and off should be satisfactory to previously defined limits.
Overspeed trips together with all other devices relative to the protection of the generator sets should be demonstrated to show that they are satisfactory.
Synchronising equipment and any associated protective devices should be demonstrated to verify correct functioning between each generating set and all other generating sets intended to operate in parallel. Reverse current, reverse power and overcurrent trips and any other safety devices should be satisfactorily demonstrated.
14.4.3 Each motor, together with its control gear, should be tested to prove the wiring and direction of rotation and then run as near as practicable to service conditions for a sufficient length of time to demonstrate that alignment, speed range, commutation, rated output and operating characteristics are satisfactory.
