Wohner31232Busbar Mounted Switch-Disconnector-Fuse, 3-Pole, 32 A, 690 V AC, 10 x 38 mm Cylindrical Fuse Links, AC-23A

Product Description

What this part is

A Wöhner 31232 switch-disconnector-fuse: a three-pole load-break switch combined with fuse holders for 10 x 38 mm cylindrical fuse links to IEC 60269-2. It mounts directly onto a busbar system rather than onto DIN rail, and it switches all three poles together while housing the three fuse links in the same body.

What these specs mean in practice

A switch-disconnector-fuse does three jobs in one device. It provides short-circuit and overload protection through the fuse links, it makes and breaks load current on demand, and it establishes a visible isolating gap so a circuit can be secured for work. Combining them removes two separate devices and the wiring between them from the panel.

The utilisation category is the specification that decides whether the device suits the load, and it is duty-specific. AC-23A means the switch is rated to make and break a highly inductive motor load, which is a far more demanding duty than resistive switching, and this device carries AC-23A at 400 V and AC-22A at 690 V. The current rating therefore has to be read together with the category and the voltage.

The 50 kA short-circuit figure is a withstand rating achieved in combination with the fuse links: the fuse clears the fault before the switch contacts are stressed, which is what allows a compact device to sit on a system with high prospective fault current. That figure applies with fuse links of operating class gG at 400 V.

Busbar mounting is the reason this style of device exists. Clipping the disconnector onto a busbar system removes the incoming cable, its termination and its routing, so outgoing ways can be added or moved on a distribution assembly without reworking the incoming side.

Published specifications

Function: busbar-mounted switch-disconnector-fuse
Poles: 3
Switching: 3-pole and 1-pole switching capability
Rated current, IEC: 32 A
Rated voltage, IEC AC: 690 V
Fuse link size: 10 x 38 mm cylindrical, IEC 60269-2
Fuse operating class: gG
Utilisation category AC (IEC 60947-3): AC-23A at 400 V, AC-22A at 690 V
Rated impulse withstand voltage Uimp: 6 kV
Short-circuit current with fuses (AC): 50 kA at 400 V (32 A)
Busbar systems: 12, 15, 20, 25 and 30 mm x 5 mm and 10 mm, and section busbars
Standards: IEC 60947-1, IEC 60947-3, GB/T 14048.3

Quantity and configuration

Sold as 1 Pc — one three-pole switch-disconnector-fuse body. Fuse links are not included, and the busbar system is not included.

Installation and setup notes

The device clamps onto the busbar system from the front, so the busbars themselves are not disturbed when a way is added. Outgoing conductors terminate on the load-side terminals. Fuse links are fitted into the three carriers in the body, and the operating mechanism isolates all three poles and gives access to the carriers in the off position. Fuse links are selected to operating class gG for the 50 kA figure to apply.

Interchange guidance

Wöhner article 31112 is a plain holder for 10 x 38 mm cylindrical fuses without the switch-disconnector function, so it is a related fuse base rather than a substitute for this device. Wöhner also builds NH fuse switch-disconnectors in sizes 00 through 3 for higher currents; those take NH blade fuse links instead of cylindrical links and are different products. A direct replacement matches Wöhner article number 31232.