ZCT211 Lead Wire Type Zero Phase ct current transformer

Electrical Specification

(Customized is available)

Problems existing in zero-sequence current transformers

Zero-sequence protection is an important part of electrical relay protection, and is widely used in large-scale coal, steel, electric power and other large power-consuming enterprises.

In order to realize the single-phase grounding protection of high-power power cables, the zero-sequence current transformer is generally used to sample the zero-sequence current and supply the relay protection equipment to realize the protection. During the commissioning process of the power system of these large enterprises, there are situations where the same load and the same switching interval are equipped with two or more zero-sequence current transformers with identical transformation ratios.

In addition, due to the substantial increase in cables and the limitation of the actual size of the zero-sequence current transformer, the number of zero-sequence current transformers used in the outgoing line of the same switchgear is increasing.

When this happens, there is a problem of how to connect multiple zero-sequence current transformers, that is, how to connect these zero-sequence current transformers, whether they are connected in series or in parallel, so that the primary winding can be more accurately reflected. (that is, three-phase cables) on the current change, this issue has been controversial in the application of zero-sequence current transformers, which has become a topic worthy of in-depth discussion.

Item	Rated Current(A)	Output Voltage Vo(mv)	Test Conditions	Over Leakage Characterstics	Temperature Characteristics -35~80℃	Dimensions (mm)
Click PN For Details						ID	OD	HT
ZCT201	30	4-5.1	lin=10mA RL=510	-10%~0%	10%Max	5.9	16	6.5
ZCT202	30	5.1-6	lin=8mA RL=750	-10%~0%	10%Max	5.8	15.2	6.1
ZCT203	50	17-21	lin=22.5mA RL=1k	-10%~0%	10%Max	9.2	21	7.3
ZCT204	30	12-15	lin=22.5mA RL=1k	-10%~0%	10%Max	9.8	20.6	6.5
ZCT205	30	12.5-15.5	lin=8mA RL=4.7k	-10%~0%	10%Max	9.3	21.3	7.2
ZCT206	50	17-21	lin=22.5mA RL=1k	-10%~0%	10%Max	12.3	26	10
ZCT207	30	7.5-8.5	lin=25mA RL=1k	-10%~0%	10%Max	15.4	29.8	10
ZCT208	60	10.2-12.5	lin=20mA RL=680	-10%~0%	10%Max	7.2	19.4	7.7
ZCT209	50	8-11.2	lin=11.25mA RL=1k	-10%~0%	10%Max	7	17.2	7
ZCT210	50	8-11.2	lin=11.25mA RL=1k	-10%~0%	10%Max	6.8	16.9	7.9
ZCT211	50	8-11.2	lin=11.25mA RL=1k	-10%~0%	10%Max	10.6	25.4	8
ZCT212	60	10.2-12.5	lin=20mA RL=680	-10%~0%	10%Max	11	23.5	8
ZCT213	60	≥300	lin=25mA RL=1k	-10%~0%	10%Max	9.4	23.8	12.7
ZCT218	60	10.2--12.5	lin=25mA RL=680	-10%~0%	10%Max	7.5	18.9	7.6
ZCT220	60	≥300	lin=25mA RL=47k	-10%~0%	10%Max	10.1	24	11.5
ZCT225	60	≥300	lin=25mA RL=47k	-10%~0%	10%Max	10.9	25.5	9
ZCT401	100	17-21	lin=22.5mA RL=1k	-10%~0%	10%Max	15	29.2	10
ZCT402	100	6.3-7.5	lin=20mA RL=370	-10%~0%	10%Max	17.5	35.9	8.8
ZCT403	250	17-21	lin=22.5mA,RL=1k	-10%~0%	10%Max	29	51	12
ZCT404	250	17-21	lin=22.5mA,RL=1k	-10%~0%	10%Max	32	55.6	12
ZCT405	250	17-21	lin=22.5mA,RL=1k	-10%~0%	10%Max	42	80*69	20
ZCT406	630	17-21	lin=25mA,RL=1k	-10%~0%	10%Max	51.3	84	26
ZCT407	800	17-21	lin=22.5mA,RL=1k	-10%~0%	10%Max	51	96*89	23
ZCT408	100	125-150	lin=500mA,RL=150	-10%~0%	10%Max	19	36	11.5
ZCT409	225	125-150	lin=500mA,RL=150	-10%~0%	10%Max	24	42	12
ZCT410	400	125-150	lin=500mA,RL=150	-10%~0%	10%Max	43	90*74	16
ZCT411	800	120-151	lin=500mA,RL=150	-10%~0%	10%Max	53	96*89	23