Download DSR 01 015 Identification of Points of Work - Document Library

UK Power Networks
DSR 01 015
v1.0
Identification of Points of Work
Owner
Name
Peter Vujanic
Title
Head of Health, Safety and Environment
Signature
01 May 2016
Date
Authoriser
Name
Dudley Sparks
Title
Operational Safety Manager
Signature
01 May 2016
Date
This document forms part of the UK Power Networks Integrated Management System and
compliance with its requirements is mandatory. Departure from these requirements may only be
taken with the written approval of the above authoriser.
Revision Record
Version number
1.0
Date published
01/05/2016
Next review date
01/05/2019
Prepared by
R Hembling
Version number
Date published
What has changed?
New document bringing standard practices across the Company
Why has it changed?
Next review date changed to 2019 to align with the printed version.
What has changed?
Why has it changed?
Next review date
Prepared by
Version number
Date published
What has changed?
Why has it changed?
Next review date
Prepared by
This printed document is valid at 06/05/17, check after this date for validity.
Page 1 of 7
UK Power Networks
DSR 01 015
v1.0
Who needs to know?
☐ All UK Power Networks Staff
☒ Asset Management
☒ Capital Programme
☒ Connections
☒ Contractors
☐ Customer Services
☐ Finance
☐ Legal
☐ G81 External website
☐ HR & Communications
☒ HSS&TT
☒ In Business HSS
☒ Safety Reps
☒ ICPs (Independent Connection Providers)
☒ IDNOs (Independent Distribution
Network Operators)
☐ Information Systems
☐ Meter Operators
☒ Network Operations
☒ EPN
☒ LPN
☒ SPN
☒ Distribution Capital Delivery
☐ Logistics
☒ Network Control
☒ Network Operations Connections
☐ Transport Services
☐ Strategy and Regulation
☒ UK Power Networks Services
☒ Airports
☒ Rail
☒ HS1, DLR & Commercial buildings
☒ MUJV / Allenby
☐ Business Development
☐ Others (specify)
Contents
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
Introduction and Purpose ............................................................................................ 3
Scope ............................................................................................................................. 3
Objective ....................................................................................................................... 3
References .................................................................................................................... 3
Definitions ..................................................................................................................... 4
Responsibilities ............................................................................................................ 4
Records ......................................................................................................................... 4
Process Detail ............................................................................................................... 4
Superseded Documents ............................................................................................... 7
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UK Power Networks
DSR 01 015
v1.0
1.0 Introduction and Purpose
This procedure details how to identify Points of Work on apparatus in different situations when
issuing Safety Documents on equipment or plant owned or operated by UK Power Networks.
Rule 4.1.1(e) of the UKPN Distribution Safety Rules states that before any part of the High
Voltage System is released for work it shall be identified at the point of work by Approved
means. This procedure and other approved procedures that exist for specific apparatus shall be
used as those approved means.
This procedure should be read and followed in conjunction with the UK Power Network’s
Distribution Safety Rules and does not authorise any departure from those rules, except where
specifically stated.
2.0 Scope
This procedure applies to identification of the point of work when Safety Documents on any
network owned or operated by UK Power Networks are issued in accordance with DSR 01 013
It also applies to redundant apparatus where no safety document (as defined in the DSRs) can
be issued.
3.0 Objective
To supplement the Distribution Safety Rules and provide an approved procedure if no other
exists for the whole of UK Power Networks
4.0 References
DSRs
Distribution Safety Rules and their appendices
DSR 01 002
HV System Operations
DSR 01 007
Identification of HV Cables
DSR 01 010
Work in Live Substations – Safe Zones of Work
DSR 01 013
Safety Documents
DSR 01 014
Excavating Near Electricity Cables
DSR 01 018
Identification of LV Cables
HSS 01 013
Clearance of Trees and Vegetation Near Overhead Lines
HSS 01 062
Undertaking On-Site (Point of Work) Assessment
HSS 01 105
Putting People to Work
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UK Power Networks
DSR 01 015
v1.0
5.0 Definitions
Hum
This refers to the noise and vibration made by Live Transformers.
ABC
Aerial Bundled Conductors (no earth screen)
ABS
Aerial Bundled Screened aerial cable (screen is earthed)
6.0 Responsibilities
6.1
Person issuing a Safety Document,
Shall ensure the point of work is clearly identified to the recipient of the Safety Document
6.2
Person receiving a Safety Document
Shall satisfy themselves that the point of work has been clearly identified and in the case of
multiple points of work under the same document the method to be used to confirm
identification at those different points, and that this is clearly understood by all members of
the working party (DSR 01 013).
7.0 Records
None
8.0 Process Detail
8.1
8.1.1
Identification, for work on ground mounted transformers.
Non-Fused Transformer (no fuses in the transformer or end box),
When the transformer is fed by a ganged switch or from where visual confirmation can be
given that all disconnectors, HV fuses or links are open or removed. And when the healthy
circuit is switched out from live, by testing for voltage and or hum (Note this should only be
used for identification where there is no suitable access to test points) before isolation, and
confirmation of lack of voltage or hum. after isolation will, provided no other local circuit
interruptions have taken place, confirm isolation.
8.1.2
Fused Transformer (Fused in the end box or transformer)
If the transformer has been switched out from live, 8.1.1 can be followed.
However a transformer with a Fused End Box or internal HV fuses could show no LV volts
even though the incoming HV is still live if the fuses have operated within the end box or
transformer. For this reason if confirmation before isolation cannot be made, then further
checks will be required.
Under a sanction-for-test or permit-to-work the incoming cable box cover will be removed
and the cable, or if a fused end box, the top and bottom of each fuse tested. Where these
connections are shrouded, with the shrouding still in place, test using the approved
capacitive tester. (Note the tester must not come into direct contact with a live
conductor).
If there are exposed conductors a suitable approved tester may be used.
Any tester shall always be proven before and after use.
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UK Power Networks
8.2
DSR 01 015
v1.0
Identification, for work on High Voltage Switchgear where the site is isolated
from the HV Network
If the switchgear is a free-standing circuit breaker or switch fuse controlling a transformer
on the same site it can be tested as in 8.1.1 with the switch closed. This will confirm
isolation.
If the switchgear is a free-standing circuit breaker or switch fuse controlling a transformer
on a different site, additional precautions shall be taken.
1. With the switch fuse/circuit breaker closed confirm the remote transformer is live (output
volts and/or hum).
2. Open the switch fuse/circuit breaker and confirm the remote transformer goes dead.
Close the switch fuse/circuit breaker and confirm the remote transformer becomes live.
This confirms the correct link between the transformer and switchgear.
3. Leaving the switch fuse/ circuit breaker closed isolate the switch fuse/circuit breaker
from its source. Confirmation of lack of output volts and/or hum at the transformer will,
provided no other local circuit interruptions have taken place, confirm isolation.
When the apparatus has been identified by one of the preceding steps, to apply the waiver
within DSR 5.1.2 all the apparatus and conductors within the zone of work must be
connected to the Circuit Main Earths at the time of document issue. To comply with this, in
the case of for example a Ring Main Unit, all switches shall be in the ‘On’ position at the
time of issue. As part of the recipient’s checks, all switches shall be closed to Earth
immediately after receipt of the Safety Document by or under the Personal Supervision of
the SAP.
8.2.1 Where it has not been possible to identify the point of work using one of the above
methods, then all switches at the isolated site shall, under instruction from the Control
Engineer be:
1. Closed to Earth, then.
2. Closed to On position prior to the issue of the safety document (this allows the waiver in
DSR 5.1.2 to take effect).
3. Closed to Earth immediately after receipt of the Safety Document by or under the
Personal Supervision of the SAP.
8.3
Identification, for work on Multi-panel Switchboards where there is live HV
connected to the switchboard
Note: Some covers on some designs of switchgear are interlocked and can only be
accessed when the relevant switch is in a suitable position.
Any covers to be removed or opened must be removed or opened under the Personal
Supervision of the SAP as required by DSR 5.4.4 who shall identify the correct cover(s) by
using the following methods:• Referring to labelling on the circuits front and rear compartments.
• Confirm the position by counting or measuring front and back of the switchgear
• Referencing manufacturer and construction drawings and commissioning and
maintenance records
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UK Power Networks
DSR 01 015
v1.0
The covers will be clearly marked and adjacent panels screened and Danger Notices
applied in accordance with the DSRs. Upon panel removal the conductors shall be tested to
confirm dead with an approved testing device.
8.4
Identification, for work on Overhead Lines with the Circuit(s) dead
The use of plans, Network Diagrams, Circuit Colours, Numbers and symbols will
determine the correct location. This shall be confirmed by following DSR 5.11.1 at the first
point of work.
Where more than one point of work is covered by the Safety Document each point of work
will need identifying by one or more of the following means:
• The SAP identifying all points of work with the permit-to-work recipient, Personally
Supervising identification at each point by following DSR 5.11.1
• If the overhead line is continuous and the point of work is in sight of another earth
applied for the work then the recipient of the permit-to-work can apply or supervise the
application of an Additional Earth at the new point of work.
• If the permit-to-work recipient is, or a member of their working party is, Authorised to test
and apply earths they can identify the points of work specified on the permit-to-work by
following DSR 5.10
8.5
Identification, for work on double circuit overhead lines with one circuit
remaining live.
The live circuit shall where reasonably practicable be set to one trip to lockout.
The SAP shall comply with DSR 5.12.3(b) at all points of work. Additionally, the SAP shall
at the first point of work identify the line to be worked on and Personally Supervise the
testing and bonding of any unearthed steelwork to earth. Then complete the identification of
the line in accordance with DSR 5.11.1. For any other points of work within the isolated
zone one of the following procedures shall be used.
• The SAP shall at every other point of work do the same as for the first point of work, or
• If the permit-to-work recipient is, or a member of their working party is, Authorised to test
and apply earths they can identify the points of work specified on the permit-to-work by
compliance with the relevant parts of DSR 5.12.3
• Note if conductors are to be replaced, the crossarm must remain connected to earth
whilst work is taking place on the pole.
8.6
Identification, for work on HV Overhead ABC and ABS (screened) conductors.
Overhead HV ABC and ABS cables can be treated the same for identification purposes.
The cables shall be Isolated and Earthed in accordance with DSR 4.1.1.
At the point where exposed conductors are accessible the conductors shall be tested and
an Earth applied under the Personal Supervision of the SAP. Depending on the
configuration of the network configuration this could be a Circuit Main Earth or Additional
Earth.
The SAP shall then visually trace the Conductors from this point to the Point of Work. If the
cable goes underground then signal identification as per DSR 01 007 shall be used to
confirm identity.
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UK Power Networks
DSR 01 015
v1.0
8.7
Identification of HV Cables is covered in DSR 01 007
8.8
Unidentified cables are covered by HSS 40 029
8.9
Identification of apparatus in Live Substations is covered by DSR 01 010
8.10 Identification, for work on redundant overhead lines
If an overhead line has been completely disconnected (This includes any cables attached to
poles or towers) from the Network and no longer appears on control diagrams a Safety
Document cannot be issued through the Control Engineer.
Steps still need to be taken to ensure safety by following the steps in 8.4 and 8.5 above and
additionally, identify that all points of possible connection to the network are completely
disconnected from the network before any work proceeds on the site.
9.0
Superseded Documents
EPN Approval 33, 55 (part)
SPN interpretations 5.10.1, 5.12.1, 5.12.3 & 5.14.1
SPN OI G43, G48-10, G50-10
LPN EOI 145
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