CTMB40 – Window-type current transformer for Cable and Bar 400A to 800A

Window-type current transformers designed for current measurement in single-phase cables up to 30 mm in diameter or bars with maximum dimensions of 40x10 mm. The range covers a wide range of primary currents, ranging from 200A to 800A AC. They are available in accuracy classes of 0.2S to 1.0.

Bar (mm): 40 x 10 ; 30 x 20 ; 15 x 30
Round cable (mm): 30
Conductor type: Single-phase
Magnetic core type: Closed
Primary current: 200A to 800A
Secondary current: 5A (1A on request)
Class 0.2S, 0.2, 0.5S, 0.5, or 1.0 depending on the size
Power (VA): 5 to 10 VA

Technical Specifications

CT Ratio

From 200A to 800A

Nominal Power

up to 10VA

Accuracy Class

Classes 0.2s, 0.2, 0.5s, 0.5 or 1.0

Terminal

Full terminal coverage, high cross-section brass terminal for added safety.

Box

Flame-retardant ABS/PC. Self-extinguishing.

Mounting

On cable or bar

Operating ambient temperature

-25 C° – +85 C°

Primary conductor

40 x 10 mm

Round conductor

Diameter 30 mm

Number of inputs

1 input

Short-time thermal current

Ith = 60 * In

Continuous thermal current

Id=1 * In

Nominal frequency

50Hz … 60Hz

Overvoltage current limiting factor

FS 5

Test voltage

3kV 1min

Maximum system voltage

0.72kV

Applicable Standards

IEC 60044-1
IEC 61869-2
VDE 0414-1
DIN57414
BS3938
BS7626
EN 61869-2

Diagrams and Dimensions

Reference Tables

Ratio	Series	Reference	Accuracy Class
Ratio	Series	Reference	1.0	0.5	0.5s	0.2	0.2s
400/5	CTMB40	CTMB40-400/5	5/10	5/10	5
500/5		CTMB40-500/5	5/10	5/10	5	5
600/5		CTMB40-600/5	5/10	5/10	7.5	7.5	7.5
800/5		CTMB40-800/5	10	10	10	10	7.5