CT-MS medium split-core AC current transformers provide a 1 A or 5 A secondary output proportional to primary current. Seven factory-calibrated primary ratings span 150–800 A. The 2.22 × 1.19 in (56.4 × 30.2 mm) sensing window opens for installation around existing conductors and bus bars.

CT-MS / CT-LS Series Current Transformers — Catalogue CT-MS Series Current Transformers — Instructions

Select & Configure Model

Base Model #	Power Supply	Frequency	Accuracy	Approvals	Normally In Stock	Add to Cart / Configure Part #

CT-	Self Powered	50/60 Hz	±1%; 150 A models ±1.5%	CE, UL Recognized - USA & Canada	Inquire	Configurator

Power Supply:

Self-powered

Frequency Range:

50/60 Hz

Accuracy:

200–800 A models: ±1%; 150 A models: ±1.5%, at 10–100% of range

Approvals:

UL Recognized component (E475131), cUR and CE; ANSI/IEEE C57.13 and IEEE C57.13.2

Case:

Medium split-core; aperture 2.22 × 1.19 in (56.4 × 30.2 mm); UL94 V-0 thermoplastic

Burden:

Ratio-dependent; see catalogue. 400:5 rating differs between documents: use 1.2 VA pending confirmation. Thermal rating 1.0 at 30°C.

Output Signal:

0–1 A or 0–5 A AC

Supply voltage:

600 V AC maximum

Linearity:

0.5%, at 10–100% of range

Rated Primary Current:

150, 200, 300, 400, 500, 600 or 800 A

Isolation Voltage:

UL tested to 4000 V AC

Choose 150, 200, 300, 400, 500, 600 or 800 A primary current with either a 1 A or 5 A secondary. Example order number: CT-0200-5-MS.

Allowable burden varies by ratio and secondary output; consult the catalogue. The catalogue and instruction sheet differ for the 400:5 burden (2.5 VA versus 1.2 VA); use 1.2 VA pending confirmation for that ratio. Never energize the transformer with its secondary open. Use a suitable shorting terminal block before disconnecting the instrument. Install with H1 facing the source and observe secondary polarity.