47 3. Starting Autotransformer
V
L-L
= 220V
Tabel 4.12 Data pengukuran kinerja motor induksi beban 70 starting
autotransform
Metode Starting
Kecepatan Putaran
Torsi Start Arus Start
Pin W
Pout W
Ƞ Nrpm
N rads
T
Ys
T
Δ s
T
S
T
N
I
Ys
I
Δs
I
S
I
N
AutoTransfo rmer
1415 148.10
- -
0.9 2
0. 6
- -
2.5 1.3
3 339.
55 88.86
26.16
4.2.2 Penyelesaian Data Percobaan
4.2.2a Penyelesaian data beban 50 resistif 1. Starting Langsung
• Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
=148.10 rads •
P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 1.6. 0.67
= 408.48W •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W
Universitas Sumatera Utara
48 •
Ƞ=
���� ���
� 100 =
88.86 �
408.48 �
x100 = 21.75
2. Starting wye-delta •
Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
=148.10 rads •
P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 2.75. 0.67
= 702.08W •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W •
Ƞ=
���� ���
� 100 =
88.86 �
702.08W
x100 = 12.6
3. Starting autotransformer •
Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
=148.10 rads
Universitas Sumatera Utara
49 •
P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 1.33. 0.67
= 339.55W •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W •
Ƞ=
���� ���
� 100 =
88.86 �
339.55 �
x100 = 26.16
4.2.2b Penyelesaian data beban 60 resistif 1. Starting Langsung
Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
=148.10 rads •
P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 1.6. 0.67
= 408.48W •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W •
Ƞ=
���� ���
� 100 =
88.86 �
408.48 �
x100 = 21.75
2. Starting wye-delta
Universitas Sumatera Utara
50 •
Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
=148.10 rads •
P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 1.6. 0.67
= 408.48W •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W •
Ƞ=
���� ���
� 100 =
88.86 �
408.48 �
x100 = 21.75
3. Starting autotransformer •
Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
=148.10 rads •
P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 1.6. 0.67
= 408.48W
Universitas Sumatera Utara
51 •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W •
Ƞ=
���� ���
� 100 =
88.86 �
408.48 �
x100 = 21.75
4.2.2c Penyelesaian data beban 70 resistif 1. Starting Langsung
• Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
=148.10 rads •
P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 1.6. 0.67
= 408.48W •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W •
Ƞ=
���� ���
� 100 =
88.86 �
408.48 �
x100 = 21.75
2. Starting wye-delta •
Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
Universitas Sumatera Utara
52 =148.10 rads
• P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 2.75. 0.67
= 702.08W •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W •
Ƞ=
���� ���
� 100 =
88.86 �
702.08W
x100 = 12.6
3. Starting autotransformer •
Nrads =
2 �
60
.
Nrpm �=3.14
=
2 �3.14
60
.1415 rpm
=148.10 rads •
P
IN
= √3.V. I
N.
Cos ϕ
Cos ϕ = 0.67
= √3. 220. 1.33. 0.67
= 339.55W •
P
Out
= T
N.m
. Nrads = 0.6 N.m . 148.10 = 88.86 W •
Ƞ=
���� ���
� 100 =
88.86 �
339.55 �
x100 = 26.16
Universitas Sumatera Utara
53
25 50
75 100
125 150
50 60
70
Beban
kecepatan torsi start
efesiensi
4.2.3 Perbandingan Hasil Pengukuran Perubahan beban dengan menggunakan tiga metode starting
