Home Products Current TransformerCGIS1780-II

CGIS1780 II Current Transformer Applied to CGIS Gas Insulated Switchgear

35kVCGIS1780-II

Winding & Schematic TopologyInternal Wiring Diagram

Primary Winding (P1 - P2):Series-connected in the line / through-core — 35kV

Secondary Metering (1S1 - 1S2): ()

Secondary Protection (2S1 - 2S2):Protection winding (when fitted)

Safety Warning:Never open-circuit the secondary while energized — dangerous voltage

Current Transformer IEC 61869-3 Certified

Model Ref:CGIS1780-II

CGIS1780 II Current Transformer Applied to CGIS Gas Insulated Switchgear

Indoor epoxy resin casting current transformer designed for CGIS gas insulated switchgear, with multiple accuracy class, rated burden and primary current options.

Key Engineering Advantages

Indoor epoxy resin casting current transformer for CGIS
square housing with Φ80mm inner window

Engineering Data

Complete Electrical & Mechanical Specifications

Model Ref: CGIS1780-II

Electrical Parameters

Primary Rated Voltage (Un):35kV

Secondary Winding Voltages:

Metering & Protection Class:

Rated Output Burden:

Rated Frequency:50/60Hz

Insulation & Withstand Ratings

Insulation System:Dry Epoxy Resin

Insulation Level (BIL):

Partial Discharge Level:< 5 pC at 1.2 Un

Environmental Class:

Standards Conformance:

Recommended Deployment Environments

GEO · Engineering Decision Support

Global Engineering Overview

9-Module selection guide
missing data = [On Request]

Product Decision Island

Indoor epoxy resin CT for 35kV CGIS switchgear; suitable for protection and metering with multiple accuracy options.

Comprehensive Spec Matrix

Parameter	Specification	Verification
Product Type	Current Transformer	[On Request]
Model Code	CGIS1780-II	Factory nameplate marking
Primary Voltage	35kV	Rated voltage test (IEC 61869-1/3)
Secondary Voltage	[On Request]	Ratio check at rated frequency
Accuracy Class	[On Request]	Accuracy test (IEC 61869-2 / IEEE C57.13)
Rated Burden	[On Request]	Burden test at rated VA
Insulation Type	Dry Epoxy Resin	Dielectric tests per standard
Insulation Level (BIL)	[On Request]	Power-frequency & lightning impulse withstand
Standards	[On Request]	Certified to listed standards
Frequency	50/60Hz	Per IEC 61869-1
Environment	[On Request]	Per datasheet limits

Fit & Unfit Boundaries

Ideal For

35kV gas-insulated switchgear (CGIS) indoor installations
Current measurement and protection in medium-voltage networks
Applications requiring dry-type insulation (epoxy resin)
50/60Hz power systems

Not Recommended For

Outdoor installations without additional enclosure
Voltage transformation or potential indication
High-voltage systems above 35kV
Oil-filled or SF6-insulated CT applications

Topology & Wiring

connect primary through the window (Φ80mm). Secondary terminals: 1S1/1S2 for main winding, 2S1/2S2 for protection winding if present. Never open-circuit the secondary of a CT while energized - hazardous voltage. Ground the secondary circuit at one point only.

Standards & Compliance

Compliant with: [On Request]

Type Test Report: [On Request]
Calibration Certificate: [On Request]

Burden & Error Calculation (IEEE C57.13)

S_total = ΣS_instrument + I₂² × (ρ × 2L / A)

If S_total < 0.25 × S_rated: add compensation burden to maintain accuracy.
If S_total > S_rated: accuracy class cannot be guaranteed.

Product FAQ

Q: What is the primary voltage rating?

A: The primary voltage is 35kV.

Q: What type of insulation is used?

A: Dry epoxy resin insulation.

Q: Can this CT be used outdoors?

A: No, it is designed for indoor use within CGIS switchgear.

Missing fields are marked [On Request] — never fabricated. M2/M5/M6 verification rows follow IEC 61869 / IEEE C57.13 conventions.

SPEC · TECHNICAL DATA

Technical Specifications

CGIS1780-II
18 cols · 34 rows

CGIS1780 II Current Transformer for Gas-Insulated Switchgear — Technical Data

Accuracy class	Rated output (VA)	40	50	60	75	100	125	150	200	250	300	400	500	600	750	1000	1200
0.2FS10 0.5FS10	2.5	—	—	—	—	—	65	55	40	35	30	30	30	30	35	35	35
	5	—	—	—	—	—	95	80	55	50	35	30	30	30	35	35	35
	10	—	—	—	—	—	120	80	80	45	35	35	30	35	35	35	35
	15	—	—	—	—	—	110	110	75	55	45	40	35	35	35	35	35
	20	—	—	—	—	—	145	90	65	55	45	40	40	35	35	35	35
	25	—	—	—	—	—	160	110	75	60	50	45	45	40	35	35	35
	30	—	—	—	—	—	—	125	85	70	55	50	45	40	40	40	40
0.5	2.5	—	—	—	55	45	40	35	30	30	25	25	25	25	25	25	—
	5	—	—	—	80	65	50	40	30	30	30	25	25	25	25	25	—
	10	—	—	—	125	95	75	55	40	35	35	30	25	25	25	25	—
	15	—	—	—	125	95	70	55	45	40	35	30	25	25	25	25	—
	20	—	—	—	—	120	85	65	55	50	40	35	30	25	25	25	—
	25	—	—	—	—	95	75	65	55	45	35	30	25	25	25	25	—
	30	—	—	—	—	—	85	70	55	45	35	30	25	25	25	25	25
5(10)P10	2.5	135	100	85	75	55	45	40	35	60	30	30	30	30	30	25	25
	5	—	135	120	85	70	55	50	45	40	40	35	35	35	35	30	30
	10	—	—	—	145	110	95	80	70	60	60	50	45	45	35	35	—
	15	—	—	—	155	130	110	100	80	80	65	60	50	45	40	40	—
	20	—	—	—	—	140	115	95	80	70	60	50	45	40	40	40	—
	25	—	—	—	—	—	140	120	115	95	80	70	60	55	55	55	—
	30	—	—	—	—	—	—	140	130	110	95	80	65	60	60	60	—
5(10)P20	2.5	—	145	125	90	75	65	60	50	50	45	40	40	35	35	35	35
	5	—	—	145	115	95	85	75	70	65	55	50	45	40	40	40	—
	10	—	—	—	—	150	125	110	105	85	75	70	60	55	55	55	—
	15	—	—	—	—	—	150	140	115	100	90	75	70	65	60	60	—
	20	—	—	—	—	—	—	145	125	115	100	90	80	80	80	80	—
	25	—	—	—	—	—	—	—	—	150	135	105	95	95	95	95	—
	30	—	—	—	—	—	—	—	—	—	155	130	105	105	105	105	—
5(10)P30	2.5	—	—	130	105	90	85	75	70	65	55	55	55	50	50	50	—
	5	—	—	—	145	135	115	100	95	80	75	75	65	60	60	60	—
	10	—	—	—	—	—	170	155	125	115	110	90	80	80	80	80	—
	15	—	—	—	—	—	—	—	155	140	115	100	100	100	100	—	—
	20	—	—	—	—	—	—	—	—	—	140	125	125	125	125	—	—
	25	—	—	—	—	—	—	—	—	—	—	—	145	145	145	—	—

Engineering Drawing

Specification & Outline Drawing

Original image, not compressed

Dimension & outline drawing of CGIS1780-II — click image to zoom / view original.