ZN85-40.5 Handcart Indoor Vacuum Circuit Breaker 1250-2000A 25-31.5kA 40.5kV Withdrawable Switchgear IEC GB Thomas Electric

Product Overview

The ZN85-40.5C is a three-phase 50 Hz, 40.5 kV handcart (withdrawable) indoor vacuum circuit breaker for metal-enclosed switchgear in power plants, substations and industrial or mining networks. It makes, carries and breaks load, overload and short-circuit currents, with rated currents of 1250-2000 A, breaking capacity 25 or 31.5 kA and capacitor-bank breaking of 630 A single / 400 A back-to-back.

Product Display

ZN85-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker - display

ZN85-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker - poster_display

Model Designation

ZN85-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker - model

Type code: ZN 85 – 40.5 C / □ – □

Z — vacuum interrupting medium
N — indoor service
85 — design sequence number
40.5 — rated voltage (kV)
C — handcart (withdrawable) execution
First □ — rated current (A)
Second □ — rated short-circuit breaking current (kA)

Example: ZN85-40.5C/2000-31.5 identifies a 40.5 kV withdrawable indoor vacuum circuit breaker of 2000 A rated current and 31.5 kA rated short-circuit breaking current.

Service Conditions

Ambient temperature: −40 °C to +40 °C
Altitude: up to 2000 m; sites above this limit require a correspondingly raised rated insulation level
Relative humidity: daily average ≤ 95%, monthly average ≤ 90%
Seismic intensity: not exceeding degree 8
Site free from fire hazard, explosion risk, heavy pollution, chemical corrosion and violent vibration
Conditions outside these limits: subject to agreement with the manufacturer

Construction

Each phase consists of a sealed vacuum interrupter cast into a solid insulated pole, mounted on a steel handcart frame together with the spring energy-storage operating mechanism. The mechanism stores closing energy in a charged spring, released electrically by the closing coil or manually, while opening is triggered by the opening coil; control and charging circuits accept AC or DC 110 / 220 V.

The complete pole set and mechanism rack in and out of the metal-enclosed switchgear on a chassis that moves between connected, test and disconnected positions, giving visible isolation without de-energising the cubicle. Mechanical interlocks coordinate racking, closing and earthing functions, and the frame carries an earthing terminal bonded to the switchgear body.

Technical Data

No.	Item	Unit	Data
1	Rated voltage	kV	40.5
2	Rated frequency	Hz	50
3	Rated current	A	1250 1600 2000
4	Rated short-circuit breaking current	kA	25 31.5
5	Rated short-time withstand current	kA	25 31.5
6	Rated short-circuit duration	s	4
7	Rated peak withstand current	kA	63 80
8	Rated short-circuit making current (peak)	kA	63 80
9	Rated lightning impulse withstand voltage (peak)	kV	185
10	1 min power-frequency withstand voltage (RMS)	kV	95
11	Rated short-circuit breaking time	ms	< 80
12	Rated operating sequence	—	O – 0.3 s – CO – 180 s – CO
13	Breaking operations at rated short-circuit current	times	20
14	Rated single capacitor bank breaking current	A	630
15	Back-to-back capacitor bank breaking current	A	400
16	Mechanical life	operations	10000
17	Rated operating voltage (AC/DC)	V	110 220

Selection note: match the rated current to the maximum continuous load current and the breaking rating to the prospective fault level at the installation point; for capacitor duty check the 630 A single-bank and 400 A back-to-back limits.

Standards

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

Technical note: tabulated values apply to the ZN85-40.5C handcart version; ratings beyond these tables or service outside the stated conditions require technical agreement between user and manufacturer.

Installation & Dimensions

Installation Diagram

ZN85-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker - installation

The unit is delivered mounted on its chassis and racked into the metal-enclosed switchgear between connected, test and disconnected positions. Primary current passes through the chassis static contacts to the busbar, secondary circuits route via the terminal block to control, protection and metering loops, and both breaker frame and switchgear body must be earthed before commissioning with all interlocks verified.

Outline dimension	View	Value (mm)
Overall width	Front	1148
Pole (phase) spacing	Front	300 + 300
Base / wheelbase width	Front	882
Overall depth	Side	903
Upper section height	Side	400
Lower section height	Side	1170

Safety notice: installation and maintenance are reserved for qualified personnel. Before energising, confirm type, rated voltage, rated current and breaking rating against the nameplate; during service keep the breaker open, earthed and de-energised for work, never bypass interlocks, and withdraw from service any pole whose vacuum interrupter has lost vacuum.

FAQs

Z stands for vacuum interruption, N for indoor service and 85 for the design sequence; 40.5 is the rated voltage in kV and C marks the handcart (withdrawable) version. The two figures after the slash give rated current in A and rated short-circuit breaking current in kA, so ZN85-40.5C/2000-31.5 is a 40.5 kV, 2000 A, 31.5 kA withdrawable indoor vacuum circuit breaker.

A spring energy-storage mechanism: closing energy is stored in a charged spring and released on command through the closing coil, while the opening coil trips the breaker. The spring is charged from an AC or DC 110 / 220 V supply or by manual charging handle.

Rated voltage 40.5 kV at 50 Hz with rated currents of 1250, 1600 or 2000 A; rated short-circuit breaking current 25 or 31.5 kA with the same values as 4 s short-time withstand; peak withstand and making currents 63 or 80 kA.

The rated lightning impulse withstand voltage is 185 kV peak and the one-minute power-frequency withstand voltage is 95 kV RMS, which are the standard insulation coordinates for 40.5 kV indoor switchgear.

Yes. It is rated for a single capacitor bank breaking current of 630 A and a back-to-back bank current of 400 A, and its 10000-operation mechanical life supports the frequent switching typical of capacitor duty.

Please specify the type code (ZN85-40.5C), rated current, rated short-circuit breaking current, short-time duration, control and charging supply voltage, the switchgear cubicle and chassis type, plus any special service conditions at the site.

ZN85-40.5 Handcart Indoor High Voltage Vacuum Circuit Breaker