SKF Baker AWA-IV 12 HO, User Manual

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Manually entering resistance measurements
Resistance measurements taken from the motor using a high-precision resistance bridge can
be manually entered instead of having the analyzer run an automatic resistance test.
Manually entered data should be line-to-line type measurements.
To enable manual data entry, click one of the manual entry buttons
(Lead 1–2 (Ohms)
; then
the results section of the Resistance test window enables the
Measured L-L
column so you
can directly enter the lead resistances taken. When you have finished entering data, click the
Accept
button.
Wye-wound resistance measurement
Using the NEMA nomenclature for a wye-wound motor, the resistance measurement for lead
1 should be made between terminals 1 and 2 with terminal 3 left floating. This
measurement will consist of coils 1–4 in series with coils 2–5. Likewise, the lead 2
measurement should be made between terminals 2 and 3 with terminal 1 left floating. The
lead 3 measurement should be made between terminals 3 and 1 with terminal 2 left floating.
Delta-wound resistance measurement
Using the NEMA nomenclature for a delta-wound motor, the lead resistance measurement
should be made between terminals 1–6 and 2-4. This measurement will be of coils 1–4 in
parallel with the series combination of coils 2–5 and 3–6. The lead 2 measurement should
be from terminals 2–4 and terminals 3–5. Likewise, the lead 3 measurement should be
made between terminals 3–5 and terminals 1–6.
After entering all data and clicking the
Accept button, the measurements will be temperature
corrected and displayed in the Temp Corrected column. The coil resistances will also be
calculated for the individual coils and displayed in the Calculated Coil R column.
Coil resistances
As discussed above, the resistance measurements made by the Baker AWA-IV are a user-
configured series or a parallel combination of coils. At the end of a resistance test, the
analyzer will calculate and display the coil resistances. If a temperature has been entered, it
will report those values. These values are found in the right-hand column of numbers in the
Resistance window. The calculation involves numerically solving for the coil resistances given
the type of winding (wye or delta) and the measured balance values.
Under some circumstances, the algorithm may fail because it cannot return a valid result
based on the values entered manually. In such cases, the analyzer will indicate that it cannot
find a solution given the balance resistance values.
PUB CM/I4 71-015 EN V13.2 Static Motor Analyzer—Baker AWA-IV User Manual 59
Baker AWA-IV software overview