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.
• UL E227616 volume #1 file number X0DW2

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.