Questions about Assemblies for Construction Sites

Are there any special requirements for power supplies for building and assembly sites?

The supply of electrical systems and equipment on building and assembly sites may only take place from assigned feed points.

The system must have a disconnection device (BGI 608 - Selection and operation of electrical systems and equipment on building and assembly sites).

Feed points are e.g.:

- Site current distributors

- Emergency power generators

- Transformers with separate windings

Does a feed point (site current distributor) on a building or assembly site have to be fitted with an RCD?
  • Circuits with plug and socket devices of In≤ 32 A (AC) must be operated via an RCD with I∆ N = 30 mA.
  • All other circuits with plug and socket devices must be operated via an RCD with I∆ N = 500 mA.
  • Depending on the usage scenario, RCDs that are sensitive to current pulses (type A) or DC/AC-sensitive RCDs are to be used.
  • Older site current distributors that do not have an RCD with I∆ N = 30 mA for circuits of In ≤ 32 A (AC) must be retrofitted! (See BGI 608 Section 3.2.1.)
Test intervals

When?

What?

By whom?

Following the setup of the feed point, prior to first use

Is the feed point in good condition? Are the protection measures effective?

Qualified electrician

Following a modification or repair

Is the feed point in good condition? Are the protection measures effective?

Qualified electrician

Retests (*) (BGV A3 § 5 instruction guidelines)
- once a year

Is the feed point in good condition? Are the protection measures effective?

Qualified electrician

Protection measures with RCD - every working day

Is the RCD working properly? (Check by actuating the test device – test button on RCD.)

Person trained in electrical work

Protection measures with RCD - once a month

Are the protection measures effective

Qualified electrician or person trained in electrical work with the aid of suitable measurement and test devices.

(*) Test intervals
Test intervals are to be defined as per the Ordinance on Industrial Safety and Health in accordance with the hazard and risk assessments.

Which additional feed points can be used for small building sites?

Which additional feed points can be used for small building sites?

  • For small building sites, the following feed points are also permitted:
  • - Small-type site current distributors
  • - Protective distributors
  • - Mobile protection devices, e.g. PRCDs
Following a feed point at a building/assembly site, how long can an extension cable with a safety plug be?
  • The loop resistance of the circuit determines the maximum permitted cable length following a feed point.
  • Ask the qualified electrician at the building site about the permitted cable length. (A qualified electrician is able to calculate the maximum permitted cable length on the basis of measurements or formulae.)
What regulations/standards apply?
  • - Standards in the VDE 0100 series: Stipulations on the setting up of power installations with a rated voltage of up to 1000 V
  • - DIN VDE 0100 Part 704: Setting up low-voltage installations - Requirements for industrial premises, rooms, and installations of a special type - Building sites
  • - Technical connection conditions for connections to the low-voltage grid (TAB) of a specific power supply company
  • - BGV A3 - Accident prevention regulations for electrical systems and equipment (previously VBG 4)
  • - BG information sheet BGI 608: Selection and operation of electrical systems and equipment on building and assembly sites
When are DC/AC-sensitive RCDs required?
  • DC/AC-sensitive RCDs are required for AC systems with a frequency of 50 Hz in conjunction with electronic equipment such as frequency converters, uninterrupted power supplies (UPSs), switching power supplies, and phase angle controls (soft starters).

 

For insulation testing on systems with RCCB type B, lines 3, 5, 7 and 4, 6, 8 must be disconnected from the terminals.

For insulation testing on systems with RCCB type B, lines 3,5,7 and 4,6,8 must be disconnected from the terminals.

For insulation testing on systems with RCCB type B, lines 3,5,7 and 4,6,8 must be disconnected from the terminals.