Hammond CT1000A 1000:5 Toroidal Current Transformer, 7.00 in Frame

The CT1000A is a 1000:5 toroidal current transformer on a 7.00 in (178 mm) frame, rated 0.3 - 1.2% accuracy with a 5 - 50 VA burden. It is built for metering 1000 A services and main feeders with a standard 5 A AC ammeter.

Construction is a toroidal design with 24" insulated secondary leads terminated in crimped ring connectors, and every model in the series has a two hole mounting bracket. It is suitable for use with a 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. The series is listed under UL E227616 volume #1, file number X0DW2.

Overall dimensions for the CT1000A are A 7.00 in (178 mm), B 1.35 in (34 mm), C 6.25 in (159 mm), D 6.25 in (159 mm), E 4.50 in (114 mm) and F 6.12 in (155 mm), with mounting slots G 0.28 in (7 mm) by H 0.37 in (9 mm). The listed shipping weight is 3.08 lbs (1.40 kg); the series table gives 3.3 lb. It is RoHS and REACH compliant.

To measure current, pass the wire carrying the current through the CT window so it acts as the primary winding, then connect the secondary to an ammeter with a 5 A movement. Its 4.50 in (114 mm) E dimension is larger than the 800:5 model's 3.50 in (89 mm); confirm fit against the drawing dimensions for your conductor or bus bar.