問題一覧
1
What is the purpose of reverse operation time delay (ROTD or 3 second) handle?
To give the time for the protection to kick in before any other operation can be done.
2
5 Checks each time you enter a S/S to operate switchgear.
Correct S/S, Correct switch name, Current switch position is as per skedule, Check switch condition, Check earth, Check local supplies are as expected
3
Which of the following indicate an OHL is capable of closing onto a fault.
F1H, F2V, Green triangle
4
On pole mounted switch what does the marking F2V stand for?
Fault rated/Cat2 Fitted with any type of arcing horns or plain break contacts/V for vertically mounted.
5
What is the difference in current breaking capacity between a vertically and horizontally pole mounted switch and why?
Vertical = 50% less current breaking capacity than horizontal.
6
If there are no markings on a pole mounted switch what is the making/breaking of the switch?
No markings means treat as Cat3 - DEAD OP ONLY.
7
When undertaking non-routine fault switching, authorised persons shall implement three specific procedures with regard to system controllers instructions. What are they?
1 Keep proper record of all messages passed by telephone or otherwise relating to the operation of the high voltage systems. 2 Read back to the sender of every such message relating to the operation of high voltage systems, ensuring accuracy. 3 Carry out operations instructed by the control engineer without unnecessary delay, then the implementation of the instructions shall be reported back to the control engineer as soon as possible.
8
What are safety locks used for?
To lock off the circuit being worked on, to prevent it from being energised until ready to be restored.
9
When a circuit is isolated by means of removable links or LV fuses, what should happen to them?
They shall be removed and kept in a safe place, commonly with the person issuing the safety document.
10
IN ORDER OF PREFERENCE, what are the 3 methods for applying the first CME?
1 A circuit breaker for first leg work 2 A rated earth switch 3 Portable earth's.
11
What is the general, 3 stage, procedure for applying a portable earth?
Use an approved voltage testing device to verify that the circuit is dead - Connect the earth leads to the earth end first - Connect earths to all phase conductors
12
Who in terms of AUTHORISATION, may operate a HV earthswitch or apply a CME?
An authorised person or a competent person acting under the personal supervision of an AP
13
Who must give permission to operate a HV earthswitch or apply CME?
The system controller
14
Who shall keep a record of the time and particulars of all HV switching?
The system controller
15
What constitutes SWITCHING as defined in the OSR
The operation of any device that makes or breaks a circuit including the application/removal of CMEs
16
If the spout shutters on HV switchgear are not to be used immediately what must happen to them?
The shutters must be locked shut and the keys accessible only to an AP
17
Who gives permission for HV switching
The system controller
18
When can HV switching take place without the appropriate authority
In an emergency
19
Can the system controller pass a HV switching instruction via third party to the authorised switcher
No
20
When the system controller has given permission for HV switching, how must the authorised person carry out the switching?And what must he do immediately after switching
It must be carried out without undue.Delay and reported back to the system controller as soon as possible
21
During switching if the switch is found to show signs of distress what must be done
No switching to take place and the system controller informed of the condition of the switchgear
22
What minimum PPE has to be worn when operating pole or structured mounted equipment
Helmet-EyeProtection-FlashJacket-RubberGloves-Yellowinsulatedwellies
23
Is it permissible to relay HV switching instructions by hand signals
No
24
Is it permissible to carry out HV switching after an agreed interval of time
No
25
Where safety locks are fitted to underground mounted switchgear. How should they be fitted in terms of their subsequent possible movement
They should be fitted so that they do not need to be removed until the circuit is being restored to service
26
What is the minimum and maximum permissible length of operating rods to be used for applying or removing a portable earth
2440mm/8ft/2rods or double that max
27
Why is it necessary to trip test a withdrawable circuit breaker after it has been removed from service and replaced
In order to prove the integrity of the secondary isolating contacts between the fixed portion and the moving portion of the circuit breaker.
28
What methods are available for electrically trip testing circuit breakers? And in what order of preference should they be used
Telly control - Local trip handle - Manual operation
29
Who makes the final decision whether or not to operate HV switch live
The holder of the Items/Schedule/ Person operating the switch
30
You are instructed to close the 'high street' switch on inspecting the switch gear.You find the labels read 'high street shops' and 'high street flats'.Which switch do you operate
None and report back to control
31
Who gives the instruction to carry out switching operation
The system controller
32
Once you have isolated a circuit what should you do with the safety lock keys
Lock them in a key safe or preferably give them to the SAP in charge of the works
33
If an item of ground mounted switch gear has spring assistance to operate the switch is it classed as dependent manual or independent manual
Independent manual
34
At hope lane S/S you have been asked to close the pulpit view switch. On inspection you find switch open with an SL and CN fitted to it.Can you close the switch
No
35
At Despair lane SS you have been asked to remove isolation and close the Dowty View switch. On inspection you find the switch open with a SL and CN fitted to it.Can you close the switch
Yes
36
You have been instructed to open and apply isolation to the Laurel Lane switch. What lock do you apply to the on/off mechanism after operating
A safety lock + Caution notice
37
List three applications where you would find an x lock
Earthing Switch, Interlock, Test access, Transformer tap changer, VT chamber
38
List one application where you would find a Z lock
Weather shield
39
List one application where you would find a Y lock
On/Off switch
40
You have been instructed to open the Oliver lane switch. Just before carrying out the operation. A customer enters the ss and asks when the supplies will be restored. What you do
Stop - Ask the customer to leave the SS - Confirm right switch and right operation - Operate and record - Talk to the customer.
41
List 4 components which will be checked before operation of any pole or structured mounted airbreak switch 'underslung'
get ans
42
List 4 pre operation checks which shall be carried out specifically for handle operated pole mounted air break switches
Right switch, Right position, Check earthing condition, Check condition of permaly
43
With regards to ABSDs air break switch disconnectors.What does an orange triangle indicate
Fault level in excess of making capability
44
With regards to ABSD's airbrake switch disconnectors.What does a green triangle indicate
Fault level less than making capability.
45
The correct hierarchy for operating switch gear assets
Remotely via remote control facilities - Remotely onsite via control panels in a different room as the switch gear being operated - Remotely via a control panel in the same room as the switchgear being operated - Remotely via an approved umbilical device or similar - Via the operating facilities on the switch game
46
Having removed a withdrawable circuit breaker from service and restored.Where must you remain when control carries out a trip test of the breaker
Outside the building
47
Operating a schedule subject to NOP2 Is it acceptable for the local controller to issue you the instruction to carry out a switching operation at a predetermined time
No
48
When carrying out unscheduled switching on overhead networks.Why must you never attempt to reverse an operation when closing onto a suspected fault
The ABSD are not able to break fault current