2/1/2018
Current Transformer Indoor Toroidal (CT Series) - Hammond Mfg.
Quality Products. Service Excellence.
Current Transformer Indoor Toroidal
CT Series
Features
Toroidal design.
Supplied with 24" insulated secondary leads, terminated with crimped ring connectors.
Suitable for use with bare (uninsulated) primary conductor in circuits up to 600 V (4 KV Hi
pot); or at higher voltages when a suitably insulated conductor is used.
All units have 5 A secondary for use with standard AC ammeters with 5 A movements.
Two hole mounting bracket on all models.
Application Data
To obtain current measurement:
1. Pass the wire carrying the current to be measured through the window of the CT
transformer (acting as a primary winding).
2. Connect the CT secondary to an ammeter with a 5 A movement.
For higher accuracy or higher VA burden rating:
1. Choose a CT with a primary which is a multiple of the required primary rating and which
has the accuracy or VA burden you require.
2. Loop the wire carrying the current to be measured through the window a number of times
equal to the multiple. This "winding" will reduce the ratio back to required primary rating.
Example "A": To obtain an accuracy of 1.2% at 10VA burden with a ratio of 100:5,
use a CT400 and loop 4 primary turns through the window.
Example "B": To obtain a 25:5 ratio, use a CT75 with 3 primary turns to yield 2%
accuracy or a CT50 with 2 primary turns to yield 3.2% accuracy.
Current Ratio
Part No.
CT50A
CT60A
CT75A
CT100A
CT150A
CT200A
CT250A
CT300A
CT400A
CT500A
CT600A
CT800A
CT1000A
CT1200A
Pri. / Sec.
50:5
60:5
75:5
100:5
150:5
200:5
250:5
300:5
400:5
500:5
600:5
800:5
1000:5
1200:5
Accuracy
%
3.2
2.4
2
2
1.2
1.2
0.6 - 1.2
0.6 - 1.2
0.6 - 1.2
0.3 - 1.2
0.3 - 1.2
0.3 - 1.2
0.3 - 1.2
0.3 - 1.2
Burden
VA
2
2
2
2
2
2
2-5
2 - 10
2 - 10
2 - 20
2 - 20
5 - 50
5 - 50
10 - 50
A
3.75
3.75
3.75
3.75
3.75
4.75
4.75
4.75
4.75
4.75
6.00
6.00
7.00
8.00
B
Overall Dimensions
C
3.25
3.25
3.25
3.25
3.25
4.25
4.25
4.25
4.25
4.25
5.25
5.25
6.25
7.25
D
3.00
3.00
3.00
3.00
3.00
4.00
4.00
4.00
4.00
4.00
5.25
5.25
6.25
7.25
E
0.87
0.87
0.87
1.20
1.20
2.20
2.20
2.20
2.20
2.20
3.50
3.50
4.50
5.50
F
2.87
2.87
2.87
2.87
2.87
3.87
3.87
3.87
3.87
3.87
5.12
5.12
6.12
7.12
1.75
1.75
1.75
1.75
1.75
1.75
1.75
1.75
1.75
1.75
1.75
1.75
1.75
1.75
Mounting Slots
G
0.22
0.22
0.22
0.22
0.22
0.22
0.22
0.22
0.22
0.22
0.28
0.28
0.28
0.28
H
0.37
0.37
0.37
0.37
0.37
0.37
0.37
0.37
0.37
0.37
0.37
0.37
0.37
0.37
Ship Wt.
Lb.
1.3
1.4
1.5
1.1
1.4
1.7
1.7
1.8
1.8
1.8
2.5
2.8
3.3
3.8
https://www.hammfg.com/electronics/transformers/instrument/ct
1/2
2/1/2018
Current Transformer Indoor Toroidal (CT Series) - Hammond Mfg.
Data subject to change without notice
© 2018. Hammond Manufacturing Ltd. All rights reserved.
https://www.hammfg.com/electronics/transformers/instrument/ct
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