Download IMO - Metering

Blondel Compliance
Blondel Compliance
• Update to IMO Wholesale Revenue Metering Standard V2.0
• Section 4.3.3 - Considerations for non-Blondel Meter
Installations
a.
b.
c.
d.
3 CT’s and 2 PT’s (phase-N) using 2.5 element meter
3 CT’s (delta connected) and 2 PT’s (phase-N) using 2 element meter
2 CT’s and 3 PT’s (69V phase-N) using a 2 element meter
2 CT’s and 2 PT’s using 2 element meter where Neutral is not
available
• Section 4.4.1 - Registration of non-Blondel Meter Installations
– At seal expiry, MI registered under 4.3.3b must be upgraded to 4.3.3a
with a conforming 2.5 element Main meter that calculates the missing
voltage and records the missing voltage (V2h) in channel 6 (ION
Meter)
Blondel Compliance
• Section 4.3.2 - Compliance with Measurement Canada
Rulings
Existing installations shall comply with any future Measurement Canada rulings on two and onehalf element metering (or two-element metering, using three delta connected current transformers
and two voltage transformers connected phase to ground). As per Measurement Canada Bulletin E24E (rev.1) dated 2002-11-29, “5.1 Effective April 1, 2003, all new and all reconstruction of
existing 3- phase 4-wire wye configured metering installations shall use metering that is compliant
to Blondel’s theorem such as 3-element metering. An example of a reconstructed metering
installation may include service upgrades and, or instrument transformer replacement.
Reconstruction of existing metering installation, sites that do not have sufficient physical space to
accommodate the additional voltage transformer will not be required to meet 5.1 above”
Blondel Compliance
Blondel Compliant
TS
3 Wire Distribution
VT
Transformer station (TS) has a wye secondary that is
either grounded through impedance or is solidly
grounded. The ground/neutral is not brought outside
the station. Three current transformers and three
voltage transformers connected phase to ground/
neutral are inputs to a 3 element meter.
M
3 Element
Blondel Compliant
TS
3 Wire Distribution
VT
Transformer station has a delta or ungrounded wye
secondary. Two current transformers and two voltage
transformers connected phase to phase are inputs to
a 2 element meter.
M
2 Element
Blondel Compliant
TS
4 Wire Distribution
VT
M
Transformer station has a wye secondary that is
either grounded through impedance or solidly
grounded. The neutral is brought outside the station.
Three current transformers and three voltage
transformers connected phase to neutral are inputs
to a 3 element meter.
3 Element
Blondel Compliant
TS
Grounding
Bank
4 Wire Distribution
VT
M
Transformer station has a delta or ungrounded wye
secondary. The neutral is brought outside the station.
Two current transformers and two voltage
transformers connected phase to phase are inputs to
a 2 element meter on the line side or the load side of
the grounding bank.
2 Element
Blondel Compliant
TS
Grounding
Bank
4 Wire Distribution
VT
M
3 Element
Transformer station has a delta or ungrounded wye
secondary. The neutral is brought outside the station.
Three current transformers and three voltage
transformers connected phase to ground/neutral are
inputs to a 3 element meter on the load side of the
grounding bank.
Blondel Compliance
• In some cases, the Metering requirements may differ
depending on the location of the Meter Installation
• Within a facility (TS)
– Grounded system requires 3 element metering. PT’s connected phaseneutral for 4 distribution system or phase-ground for 3 wire
distribution system.
– Ungrounded system requires 2 element metering*
• Within a distribution system (outside of TS)
– 4-Wire distribution requires 3 element metering - 27.6 kV Wye
– 3-Wire distribution requires 2 element metering - 46 kV (Wye or
Delta)
Blondel Compliance
• What happens when meter is not located at the defined Meter
Point (feeder meter located outside of the TS)?
– Meter Installation is 2 element but declared non-Blondel
– Non-Blondel MEC’s apply
• Do we need to simplify the metering requirements for NEW
meter installations?
– 3 element meter installation irregardless of the # of wires (3 or 4) or
meter location.
– Research industry practices and develop standard.
• IMO and NRC to perform study on non-Blondel installations
(2 element metering on a grounded system).