ZN23-40.5 Handcart Indoor Vacuum Circuit Breaker 40.5kV 1250-2000A 25-31.5kA

Product Overview

The ZN23-40.5 is a three-phase 50 Hz withdrawable, center-mounted handcart indoor vacuum circuit breaker rated 40.5 kV for protection in power plants, substations and industrial or mining networks. Currents of 1250-2000 A pair with breaking of 25 or 31.5 kA, a 4 s short-time rating and 630 A capacitor breaking, suiting frequent duty such as metallurgy and arc-furnace loads.

Product Display

ZN23-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker - display

ZN23-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker - poster_display

Model Designation

ZN23-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker - model

Model format: ZN 23 − 40.5 C / □ − □

Z — Vacuum circuit breaker
N — Indoor installation
23 — Design sequence number
40.5 — Rated voltage (kV)
C — Handcart (withdrawable) type
First □ — Rated current (A)
Second □ — Rated short-circuit breaking current (kA)

Example: ZN23-40.5C / 2000 − 31.5 identifies a 40.5 kV handcart indoor vacuum circuit breaker of 2000 A rated current with 31.5 kA rated short-circuit breaking current.

Service Conditions

Ambient temperature: −40 °C to +40 °C
Altitude: not exceeding 1000 m (at higher altitude the rated insulation level is raised accordingly)
Relative humidity: daily average ≤ 95%, monthly average ≤ 90%
Seismic intensity: not exceeding degree 8
Site free from fire, explosion hazard, serious pollution, chemical corrosion and violent vibration

Construction

The arc is extinguished inside sealed vacuum interrupters, giving a high insulation level of 185 kV impulse and 95 kV power frequency, long electrical endurance and no fire or explosion risk. The spring energy-storage mechanism uses a 275 W charging motor on AC/DC 220 or 110 V (storage time under 15 s, manual charging also possible) and closes from stored energy, with closing and opening solenoids on the same control voltages.

The breaker is assembled on a chassis as a withdrawable center-mounted unit that racks between the connected, test and disconnected positions of metal-enclosed switchgear, so it can be isolated or removed while the cubicle stays energised. Primary current transfers through the chassis static contacts, secondary circuits reach the control, protection and measurement loops via the terminal block, and the frame and switchgear body are earthed reliably before commissioning.

Technical Data

No.	Item	Unit	Data
1	Rated Voltage	kV	40.5
2	Rated Lightning Impulse Withstand Voltage (peak)	kV	185
3	1 min Power-Frequency Withstand Voltage	kV	95
4	Rated Frequency	Hz	50
5	Rated Current	A	1250 1600 2000
6	Rated Short-Circuit Breaking Current	kA	25 31.5
7	Rated Short-Time Withstand Current	kA	25 31.5
8	Rated Peak Withstand Current	kA	63 80
9	Rated Short-Circuit Duration	s	4
10	Rated Short-Circuit Breaking Time	ms	≈ 90
11	Rated Short-Circuit Making Current (peak)	kA	63 80
12	Rated Operating Sequence	—	O – 0.3 s – CO – 180 s – CO
13	Closing Time	ms	50 – 85
14	Opening Time	ms	40 – 85
15	Breaking Operations at Rated Short-Circuit Current	times	20
16	Mechanical Life	operations	10000
17	Rated Capacitor Bank Breaking Current	A	630
18	Energy-Storage Motor Rated Power	W	275
19	Energy-Storage Motor Rated Voltage	V	AC/DC 220, 110
20	Energy-Storage Time	s	< 15
21	Closing / Opening Solenoid Rated Voltage	V	AC/DC 220, 110
22	Overcurrent Release Rated Current	A	5
23	Auxiliary Switch Rated Current	A	10

Selection note: select the 25 or 31.5 kA rating from the prospective fault current at the switching point and the rated current from the maximum continuous load; for capacitor duty confirm the 630 A bank breaking rating against the installation.

Standards

The breaker is designed and type-tested to GB/T 1984 for AC high-voltage circuit breakers and to IEC 62271-100, with manufacturing and inspection carried out according to DL/T 403 for indoor high-voltage vacuum circuit breakers of 3.6 kV to 40.5 kV.

Technical note: parameters outside the published tables follow the technical agreement; binding values are those on the nameplate and in the approved specification for the order.

Installation & Dimensions

Installation Diagram

ZN23-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker - installation

The unit is supplied as a withdrawable handcart breaker on a chassis that racks between the connected, test and disconnected positions of 40.5 kV metal-enclosed switchgear. Verify all mechanical interlocks before operation and earth the breaker frame and switchgear body reliably before commissioning.

Outline Dimension	Value (mm)
Overall Width	1410
Overall Height	1690
Upper Section Height	750
Lower Section Height	861

Safety notice: installation, operation and maintenance are reserved for qualified personnel. Before energising, verify type, rated voltage, rated current and breaking rating against nameplate and terminal markings; during service keep the breaker open, earthed and de-energised for work. Never commission a unit with a lost-vacuum interrupter, and never bypass the mechanical interlocks.

FAQs

In the type code Z marks a vacuum circuit breaker, N indoor service, 23 the design sequence number and 40.5 the rated voltage in kV; C denotes the handcart withdrawable type, while the two following boxes set the rated current in amperes and the rated short-circuit breaking current in kiloamperes.

A spring energy-storage mechanism charged from an AC or DC 220 / 110 V supply or by manual handle; charging completes in under 15 s and closing is performed from the stored energy with reliable mechanical interlocking.

The rated lightning impulse withstand voltage is 185 kV peak and the 1 min power-frequency withstand voltage is 95 kV, the standard insulation co-ordination values for 40.5 kV indoor switchgear.

Rated currents of 1250, 1600 and 2000 A combine with rated short-circuit breaking currents of 25 or 31.5 kA; the short-time withstand current equals the breaking rating for 4 s, and peak withstand and making currents are 63 or 80 kA.

Yes. Vacuum interruption gives a long electrical life and the mechanism is rated for 10000 mechanical operations, so the breaker withstands heavily switched loads such as metallurgical plants and arc furnaces; it also breaks capacitor bank currents up to 630 A.

State the rated voltage, rated current, rated short-circuit breaking current, short-time duration, control and charging supply voltage, the switchgear cubicle and chassis type, and any special service conditions at the installation site.

ZN23-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker