Monday, October 31, 2016

Inspection Schedule Checklist According to BS 7671 in Electrical Installations

Source: www.iet.org


Inspection Schedule Checklist


Methods of protection against electric shock

Both basic and fault protection:
(i) SELV (ii) PELV (iii) Double insulation (iv) Reinforced insulation

Basic protection:
(i) Insulation of live parts (ii) Barriers or enclosures (iii) Obstacles
(iv) Placing out of reach

Fault protection:
(i) Automatic disconnection of supply:
Presence of earthing conductor
Presence of circuit protective conductors
Presence of protective bonding conductors
Presence of supplementary bonding conductors
Presence of earthing arrangements for combined protective and functional purposes
Presence of adequate arrangements for other sources, where applicable

FELV
Choice and setting of protective and monitoring devices (for fault and/or overcurrent protection)

(ii) Non-conduct ing location:
Absence of protective conductors

(iii) Earth-free local equipotential bonding:
Presence of earth-free localequipotential bonding

(iv) Electrical separation:
Provided for one item of current-using equipment
Provided for more than one item of current-using equipment

Additional protection:
Presence of residual current device(s)
Presence of supplementary bonding conductors

Prevention of mutual detrimental influence:
(a) Proximity to non-electrical services and other influences
(b) Segregation of Band Iand Band II circuits or use of Band II insulation
(c) Segregation of safety circuits

Identification
(a) Presence of diagrams, instructions, circuit charts and similar information
(b) Presence of danger notices and other warning notices
(c) Labelling of protective devices, switches and terminals
(d) Identification of conductors

Cables and conductors

  • Selection of conductors for current-carrying capacity and voltage drop
  • Erection methods
  • Routing of cables in prescribed zones
  • Cables incorporating earthed armour or sheath, or run within an earthed wiring system,or otherwise adequately protected against nails, screws and the like
  • Additional protection provided by 30 mA RCD for cables concealed in walls (where required in premises not under the supervision of a skilled or instructed person)
  • Connection of conductors
  • Presence of fire barriers, suitable seals and protection against thermal effects


General

  • Presence and correct location of appropriate devices for isolation and switching
  • Adequacy of access to switchgear and other equipment
  • Particular protective measures for special installations and locations
  • Connection of single-pole devices for protection or switching in line conductors only
  • Correct connection of accesso ries and equipment
  • Presence of undervoltage protective devices
  • Selection of equipment and protective measures appropriate to external influences
  • Selection of appropriate functional switching devices




Popular Posts