ted below are used in this Guideline
(other capitalized terms not defined here can be found in the ISO Tariff and
Metering Protocol):
Revenue Meter - The meter that is being utilized to meter the generator
output or site load, auxiliary usage or power flow at a tie line or other
interconnection point.
NIST - The National Institute of Standards and Technology
Interchange Point - Indicates the location where electrical energy passes
from one Control Area to another. For Intertie locations, the convention OUT
or EXPORT signifies energy flow out of the California ISO Control Area and
IN or IMPORT signifies energy flow into the California ISO Control Area. For
Intratie locations the OUT/IN or EXPORT/IMPORT convention is based on
agreements between the owners
Compensation Ratio and Phase Angle Correction Factors that are applied
to Revenue Meters to adjust for CT/VT inaccuracies as well as power
transformer and/or line losses when required by ISO standards.
Uncompensated - no correction factors are applied for CT/VT, transformer
or line losses.
Out - Indicates the flow of electrical energy (KWH and/or KVARH) delivered
by the ISO Control Area. NO.
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In - Indicates the flow of electrical energy (KWH and/or KVARH)received by
the ISO Control Area.
V
ISO AUTHORIZED METER INSPECTORS SCOPE OF AUTHORITY
The ISO Authorized Inspector has the authority to audit and verify any
metering installation that is either ISO approved or is seeking ISO approval.
The ISO Authorized Inspector shall also have access authority to all ISO
approved metering installations. However, the ISO Authorized Inspector must
have approval from ISO Meter Engineering prior to seeking access and must
comply with local safety and policy requirements when performing work within
the ISO Metered Entitys facilities.
In order for the ISO Authorized Inspector to be able to work within the ISO
Metered Entitys facilities, the ISO Authorized Inspector may be required to
class='doin' >attend a special training class provided and paid for by the Metered Entity to
become certified by the ISO Metered Entity to enter and audit ISO metering
systems within the ISO Metered Entitys facilities.
The ISO Authorized Inspector shall have the authority to work in or inspect
any area associated with the ISO revenue metering circuit. This includes the
areas where the instrument transformers are installed, the secondary
instrument transformer circuit, the ISO revenue metering enclosure and,
where implemented, the ISO local meter data server. The ISO Authorized
Inspector shall also have access rights to any area where the ISO meter data
communication circuits are routed.
The ISO Metered Entity has the right to escort the ISO Authorized Inspector
to any area of their facility and to witness any test requested by the ISO
Authorized Inspector.
The ISO Metered Entity shall assist the ISO Authorized Inspector when
access is required to areas of the facility which the ISO Metered Entity or ISO
Authorized Inspector deem to be critical areas or areas having extreme safety
risks.
The ISO may exercise the option of performing inspection and certification of
meters at ISO interties, intraties, governmental agencies and non-ISO
metered entities.
VI
ISO METER INSPECTORS RESPONSIBILITIES
The ISO Authorized Inspector shall be responsible for contacting the ISO
Metered Entity to schedule an initial installation verification test to see if the
metering facility meets ISO certification. NO.
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The ISO Authorized Inspector shall notify ISO Meter Engineering of all
scheduled visits to the ISO Metered Entitys facilities where the sole purpose
is to perform the initial certification. The ISO Meter Engineer will schedule the
work on the MDAS Calendar. The ISO Authorized Inspector shall provide the
ISO at least a five (5) day notice and receive confirmation from the ISO prior
to proceeding with the inspection to ensure the ISO Authorized Inspector has
all the pertinent data needed for the initial certification.
The ISO Authorized Inspector must be certified by ISO to perform installation
verifications and audits for ISO. The ISO Authorized Inspector must display
his/her credentials (i.e. ISO-provided badge) to the ISO Metered Entitys
representatives to obtain access to the facility.
The ISO Authorized Inspector shall display his/her ISO badge while at the
ISO Metered Entitys facility.
ISO Engineers may perform periodic audits. The ISO will contact companies
providing ISO Meter Inspection Services in the event theirservices are
desired.
Documentation from all ISO authorized inspection or maintenance work shall
be submitted to the ISO within five (5) business days.
Any installation failing ISO certification should be so documented on the site
verification form and the form sent to ISO within five (5) business days. The
ISO Authorized Inspector shall also contact the ISO Metered Entity primary or
secondary contact and ISO prior to leaving the site to inform them of any
certification failures.
For existing facilities that have insufficient data to establish instrument
transformer accuracy, the Inspector shall provide a written list of the data
required from the ISO Metered Entity to complete the certification package
documentation.
VII
PROCEDURES
A. Initial Site Verification and Meter Test Procedures for ISO Meter
Installations
i. Intent - The site verification procedure will be utilized to verify the
metering circuit meets ISO criteria by documenting the accurate application
and proper operation of all equipment in the revenue metering circuit.
ii. Description - The purpose of this site verification procedure is to identify
the duties of the person that will carry out the verification process for initial
transformer rated ISO metering sites. The person completing this procedure
shall have a working knowledge of the instrument transformers, meters, local NO.
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data server, and other associated metering equipment as well as being
knowledgeable of ISO certification guidelines.
iii. Instrument Transformers
(Name Plate Data) - Visually inspect the primary connections of the current
transformers. Read and record all the current transformer nameplate data on
the Site Verification Data Sheet.
The nameplate data should include the following information:
Manufacturer, Type, Current Transformer Ratios, Burden Rating, Rating
Factor, BIL, and Accuracy Class.
Current transformers shall comply with ANSI 0.3 or 0.15 Accuracy Class
for metering current transformers for B0.1 through B1.8 burden ratings.
For existing facilities, ISO-approved correction factor algorithms may be
used to compensate for worst than ANSI 0.3 Accuracy Class.
If the CTs are not accessible due to energized components or extensive
disassembly is required that may impact plant availability, note the
unavailability and request the ISO Metered Entity to identify a scheduled
outage when the CT nameplate data may be accessed safely. Such
schedule shall be subject to ISO approval.
(Phase and Polarity Check) - Verify that polarity marks on all CTs are
following the same convention (i.e. all polarity marks connected using the
same convention, e.g., facing the same source). Note that CT and VT polarity
marks normally face the ISO Grid
If there is more than one primary conductor passing through the current
transformer, then verify the phasing. The purpose of this is to visually
check the current transformer primary connections to ensure they are
properly installed.
If the CTs are not accessible due to energized components or extensive
disassembly that may impact plant availability, note the unavailability and
request the ISO Metered Entity to identify a scheduled outage when the
CT nameplate may be accessed safely. Such schedule shall be subject to
ISO approval.
(Ratio Check) - Verify that the stated CT ratio matches the manufacturers
nameplate ratio.
If the CTs are not accessible due to energized components or extensive
disassembly that may impact plant availability, note the unavailability and
request the ISO Metered Entity to identify a scheduled outage when the NO.
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CT nameplate may be accessed safely. Such schedule shall be subject to
ISO approval.
(Burden Test) - The calculated or tested burden from all the equipment in the
current transformer circuit should be less than the current transformer burden
designated on the nameplate (reference ANSI Standard Burdens for Current
Transformers). Burdens include the burden given in the ISO Metered Entitys
site documentation plus the burden of the ISO metering equipment.
Review the CT test data (ratio and phase angle test at specified burdens)
when available, and the ISO Metered Entitys calculations (TCF at applied or
actual circuit burden) to verify the CTs meet the required ANSI 0.3 metering
accuracy requirements.
iv. Voltage Transformers
(Name Plate Data) - Visually inspect the primary connections of the voltage
transformers. Record all the voltage transformer