WorksheetsExamination 2382-10 Questions
Total questions: 41
Worksheet time: 21mins
The external influence code ACM requires IP rated equipment to
IPX4
IPX1
IPO
IPX2
AS 7671 is a
document designed solely for the use of electricians
legal document used in a court of law
Bon statutory document
statutory document
The fundamental principles of BS7671 state that persons and livestock shall be protected against injury as a consequence of over voltages originating from
motors running
the operation of circuit breakers
atmospheric events
voltage recovery
The fundamental principles of BS 7671 covering the protection against voltage disturbances etc., states that the installation shall have an adequate level of immunity against
the weather
electromagnetic disturbances
voltage loss
vibration
What is the maximum As for a 10A type C circuit breaker protecting a standard discharge type lighting circuit?
1.15 Ohms
2.30Ohms
1.44Ohms
1.92Ohms
A double insulated hand held electric drilling machine is known as
class II equipment
a DeWalt
class HI equipment
class I equipment
An electrical installation certificate should be signed by
the local authority
a competent person
the customer
the REC
When considering external influences, the code AD4 requires IP rated equipment to
IPXO
IPX1
IPX4
IPX5
The external influence code AD1 requires IP rated equipment to
IPX4
IPX1
IPXO
IPX2
When considering external influences, the code AA5 relates to the ambient temperature range
-5°C to +45°C
-65°C to +5°C
+5°C to +40°C
-25°C to 0°C
When considering external influences, the code AA1 relates to the ambient temperature range
-5°C to +45°C
-60°C to +5°C
+5°C to +40°C
-25°C to 0°C
Electrical installations shall be divided into circuits to
allow easier access to the installation
allow more even distribution of power
allow for expansion without changing the maximum demand
reduce electromagnetic interference
One method of determining the external loop impedance is by taking a reading at
the origin of supply
the supply and furthest outlet
the supply and subtracting the values of R1 + R2
the furthest outlet from the supply origin
The maximum disconnection time for a 230V a.c. final circuit not exceeding 32 amps, with a TT supply is
3s
0.2s
0.5s
5ms
The maximum Zs for a 16A Type B circuit breaker protecting a fixed appliance is
1.87 Ohm
0.87Ohm
2.40Ohm
2.87Ohm
Undervottage protection is required when the restoration of power may cause
accidental RCD tripping
unexpected stalling of the motor
overload activation
unexpected start-up of the machinery
A device which cuts off all or part of an installation from every source of electrical energy provides
emergency switching
isolatior
a fireman's switch
partial disconnection
For a 32A Type B circuit breaker protecting a standard final ring circuit, the maximum Zs would be
0.70 Ohm
0.30 Ohm
1.44 Ohm
0.20 Ohm
In a TT installation, distribution circuits must satisfy a disconnection time of
5s
1s
0.6s
0.2s
A residual current device (RCD) works by
a magnetic device operating in the event of a fault between five and earth
a magnetic device operating in the event of a fault between neutral and earth
a thin element operating in the event of a fault between neutral and earth
a thin element operating in the event of a fault between live and earth
A RCBO offers protection against
short circuit current
short circuit and earth fault current
short circuit and overload current
basic contact
Protective measures against electric shock can be achieved by automatic disconnection of the supply and in systems additional protection by means of an red shall be provided for
mobile equipment with a current rating exceeding 32 A
mobile equipment with a current not exceeding 22 A
socket outlets with a rated current exceeding 20 A
socket outlets with a rated current not exceeding 20 A
Protective measures against electric shock can be achieved by automatic disconnection of the supply and in systems additional protection by means of an red shall be provided for
socket outlets with a rated current exceeding 20 A
socket outlets with a rated current not exceeding 13 A
mobile equipment with a current rating not exceeding 32 A
mobile equipment with a current rating exceeding 32 A
In a.c. systems in the event of the failure of basic protection, additional protection may be provided by
supplementary bonding
a time delay 100mA RCD
an RCD with an operating current not exceeding 30mA
electrical separation
If a fault occurs in the HV system, and a magnitude of fault voltage of 430 volts occurs between exposed conductive parts and earth on the LV installation. What is the maximum tolerable duration of the fault?
10 ms
100 ms
200 ms
300 ms
If a Line conductor of an IT system is earthed accidentally, the insulation and components rated for the Line to Neutral voltage can be temporarily stressed with a higher voltage. What value can this stress voltage reach up to?
U=V3 U0
U=3U0
U=V U0
U=U0
Nuisance tripping from a large transformer installation can be prevented by
the use of an RCD
the use of a C type MCB
the use of a B type MCB
the use of a D type MCB
In order to reduce the effects of eddy currents when conductors are drawn through a steel conduit system, they should be arranged so that
they are terminated in the correct phase sequence
each conductor of an individual circuit takes approximately the same current
they are physically separated from the conductors of other circuits within the conduit
they are not individually surrounded by the ferrous material
If a cable is buried in a wall less than 50mm depth and is not protected by metallic enclosures, the additional protection required is
RCD protection -
MCB protection
supplementary bonding
external notification of cable routes
At which one of the following terminations would a warning notice NOT need to be attached
a copper water pipe
a bonded gas pipe
an earthing terminal within a consumer unit
an earth electrode
When determining design current, the correction factor that is applied to a BS3036 rewirable fuse is
0.752
0.527
0.725
1.725
A BS1361 protective device is also known as a
circuit breaker
cartridge fuse
RCD
semi enclosed rewirable fuse
An installation protected by an RCD shall have a fixed notice stating
the test button should be pressed occasionally
the test button should be pressed monthly
the test button should be pressed quarterly
the test button should be pressed at 6 monthly intervals
When insulated a PEN conductor shall be identified with
blue insulation along its length
green insulation and blue markings at the termination
green and yellow insulation and blue markings at the termination
green and yellow insulation along its length
Outdoor lighting does NOT involve
shelters
festoon lighting
road trafic signals
floodlighting
Where it is necessary to install cables within a wall consisting of a metal construction, the circuit should
adequately bond the studwork
be RCD protected
be MCB protected
be sheathed in metallic conduit
Where it is necessary to limit the consequences of the risk of fire due to fault currents, an RCD
shall be installed at the end of the circuit to be protected
shall be installed at the origin of the circuit to be protected
is used to switch off the line conductor in the event of a faun
is used to switch off the neutral conductor in the event of a fault
In Great Britain the use of Combined protective and neutral (PEN) conductors is prohibited in consumers installations by which regulations?
The Electricity at Work Regulations 1989
The Supply of Machinery (Safety) Regulations 1992
The IEE Wiring Regulations
The Electricity Safety, Quality and Continuity Regulations 2002
In Great Britain the use of Combined protective and neutral (PEN) conductors is prohibited in consumers installations. One of the exceptions from this is
where the supply is feeding an agricultural installation
where the installation is supplied by a privately owned transformer which has a metallic connection with the distributors network
where the supply is obtained from a private generating plant
where the supply is feeding a swimming pool
Where a generating set is used as an additional source of supply in parallel with other sources, it shall be instated
on the supply side of all the protective devices for the final circuits of the installation with a number of additional requirements
on the supply side of all the protective devices for the final circuits of the installation with no additional requirements
on the load side of all the protective devices for the final circuits of the installation with no additional requirements
on the load side of all the protective devices to the final circuit which must be connected by plug and socket
Regarding auxiliary supplies to safety services, the maximum changeover time refers to
how long the safety source can supply the rated power output to the safety service
the frequency (in cycles per second) of the auxiliary supply feeding the safety service
how often maintenance has to be carried out on the auxiliary supply
the time It takes for the safety source to s
