Current Transformer Selection Guide

ESCT-RC Rogowski Coil (Included)

The SDM630MCT-RC variant uses ESCT-RC flexible Rogowski coils with 85mV/kA output.

Specifications

Parameter	Value
Current range	10A – 100kA
Output	85mV per 1000A
Accuracy	≤1.0% (20–120% In)
Linearity	≤0.5%
Phase error	≤1°
IP rating	IP65
Operating temperature	-30°C to +70°C
Compliance	CE, RoHS

Available Models

Model	Rated Current	Coil Type	Window Size
ESCT-RC16	200A	A	16mm
ESCT-RC24	400A	A	24mm
ESCT-RC36	600A	A	36mm
ESCT-RC60	800A	B	60mm
ESCT-RC80	1000A	B	80mm
ESCT-RC100	2000A	C	100mm
ESCT-RC125	3000A	C	125mm
ESCT-RC150	5000A	C	150mm
ESCT-RC180	8000A	D	180mm
ESCT-RC200	10kA	D	200mm
ESCT-RC225	20kA	D	225mm
ESCT-RC240	40kA	D	240mm

CT Family Comparison (All Eastron Families)

Family	Type	Range	Output	Accuracy
ESCT-RC	Rogowski Coil	200A–40kA	85mV/kA	≤1%
ESCT-xxx	Split Core	100A–800A	333mV	Class 0.5 or 1
ESCT-xxx-1A	Split Core	100A–800A	1A	Class 0.5 or 1
ESCT-xxx-5A	Split Core	100A–800A	5A	Class 0.5 or 1
ECS-xxx	Solid Core	30A–150A	333mV	Class 1
ECS-xxx-1A	Solid Core	30A–150A	1A	Class 1
ECTL-xxx	Split Core (large)	600A–5000A	333mV	Class 0.5
ECTL-xxx-1A	Split Core (large)	600A–5000A	1A	Class 0.5
ECTL-xxx-5A	Split Core (large)	600A–5000A	5A	Class 0.5
ECSR-xxx	Solid Core (round)	150A–400A	333mV/1A	Class 0.5
ESCR-xxx	Solid Core (round)	60A–200A	333mV/1A	Class 1
ECTB-xxx	Split Core (busbar)	600A–5000A	5A	Class 0.5

CT Ratio Configuration

The CT ratio must match the installed Rogowski coil model. Configure via:

• LCD menu: Hold E button 3s → password 1000 → Set Ct1/Ct2/Ct3
• Modbus register 40063: Write rated current value (e.g., 2000 for ESCT-RC100)
• Range: 1–2000 (default: 1)

Example Configuration

Coil Model	Rated Current	CT Ratio Setting
ESCT-RC100	2000A	Ct1/Ct2/Ct3 = 2000
ESCT-RC150	5000A	Ct1/Ct2/Ct3 = 5000
ESCT-RC80	1000A	Ct1/Ct2/Ct3 = 1000