IEC 60034-2-2:2010 pdf Rotating electrical machines – Part 2-2: Specific methods for determining separate losses of large machines from tests – Supplement to IEC 60034-2-1
1 Scope
This part of IEC 60034 applies to large rotating electrical machines and establishes additional
methods of determining separate losses and to define an efficiency supplementing
IEC 60034-2-1 . These methods apply when full-load testing is not practical and result in a
greater uncertainty.
NOTE In situ testing according to the calorimetric method for full-load conditions is recognized.
The specific methods described are:
– Calibrated-machine method.
– Retardation method.
– Calorimetric method.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60034-1 , Rotating electrical machines – Part 1: Rating and performance
IEC 60034-2-1 , Rotating electrical machines – Part 2-1: Standard methods for determining
losses and efficiency from tests (excluding machines for traction vehicles)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60034-1 and
IEC 60034-2-1 apply, as well as the following.
3.1 calibrated machine
machine whose mechanical power input/output is determined, with low uncertainty, using
measured electrical output/input values according to a defined test procedure
3.2 calibrated-machine method
method in which the mechanical input/output to/from an electrical machine under test is
determined from the measurement of the electrical input/output of a calibrated machine
mechanically coupled to the test machine
3.3 retardation method
method in which the separate losses in a machine under test are deduced from the
measurements of the deceleration rate of its rotating components when only these losses are
present
5 Basic requirements
5.1 Direct and indirect efficiency determination
Tests can be grouped in the following categories.
5.1 .1 Direct
Input-output measurements on a single machine are considered to be direct. This involves the
measurement of electrical or mechanical power into, and mechanical or electrical power out of
a machine.
5.1 .2 Indirect
Measurements of the separate losses in a machine under a particular condition are
considered to be indirect. This is not usually the total loss but comprises certain loss
components. The method may, however, be used to calculate the total loss or to calculate a
loss component.
The determination of total loss shall be carried out by one of the following methods:
– direct measurement of total loss;
– summation of separate losses.
NOTE The methods for determining the efficiency of machines are based on a number of assumptions. Therefore,it is not possible to make a comparison between the values of efficiency obtained by different methods.
5.2 Uncertainty
Uncertainty as used in this standard is the uncertainty of determining a true efficiency. It
reflects variations in the test procedure and the test equipment.
Although uncertainty should be expressed as a numerical value, such a requirement needs
sufficient testing to determine representative and comparative values. This standard uses the
following relative uncertainty terms:
– “low” applies to efficiency determinations based solely upon test results;
– “medium” applies to efficiency determinations based upon limited approximations;
– “high” applies to efficiency determinations based upon assumptions.
5.3 Preferred methods
It is difficult to establish specific rules for the determination of efficiency. The choice of test to
be made depends on the information required, the accuracy required, the type and size of the
machine involved and the available field test equipment (supply, load or driving machine).
Preferred methods for large machines are given in Table 1 .
IEC 60034-2-2:2010 pdf Rotating electrical machines – Part 2-2: Specific methods for determining separate losses of large machines from tests – Supplement to IEC 60034-2-1
