Front plate mounting

Used on printed circuit boards

Design

The 3SB3 series is a modular range of commanding and signaling devices for front panel mounting and rear conductor connection. As an alternative, individual elements can also be supplied for use on printed circuit boards. Complete units are offered for the most commonly used applications.

The 3SB3 series is available:

• Made of molded plastic in flat, round and square design
• Made of metal in round design.

The devices are of modern industrial design and can be mounted rapidly by a single person. The operating surfaces of the pushbuttons and illuminated pushbuttons are concave. The lenses of the indicator lights are convex.

The metal version with a high degree of protection according to IP67 and NEMA 4 is available for the world market.

One command point comprises:

• An actuator or lens assembly in front of the control panel
• A holder for mounting behind the control panel
• Up to 3 contact blocks and/or 1 lampholder behind the control panel
• A comprehensive range of accessories for inscription

Mounting of the contact blocks

Two contact blocks can be snapped onto the actuator in the standard version.

When three contact blocks or illuminated actuators are required, an additional holder must be plugged onto the actuator from the rear.

• 3SB39 01-0AB holder for 3 contact blocks or for 2 contact blocks and 1 lampholder
• 3SB39 01-0AC holder with pressure plates for actuating a central contact block when using a selector switch, key-operated switch and twin pushbutton with 3 contact blocks.

For illuminated pushbuttons, illuminated switches and illuminated selector switches the holder is included in the scope of supply as standard.

Standards

IEC 60947-1, EN 60947-1.

IEC 60947-5-1, EN 60947-5-1,

IEC 60947-5-5, EN 60947-5-5 for EMERGENCY-STOP mushroom pushbuttons.

Contact blocks and lampholders

The contact blocks are fitted with slow-action contacts (NO contact or NC contact) with double operating contacts. These ensure a high switching reliability even with small voltages and currents, such as 5 V/1 mA. They are suitable for use in solid-state systems as well as conventional controls.

The switch contacts of the NC contact are positively driven.

For illuminated elements, lampholders with an integrated LED or with a base for replaceable bulbs can be supplied.

Contact blocks and lampholders feature terminal designations according to EN 50013.

Connection method

The devices are available with

• Screw terminal (box terminals)
• Spring-type terminal or
• Solder connection (0.8 mm ? 0.8 mm solder pins).

The devices with screw terminals have open terminals, screws that cannot be lost, funnel-shaped cable entries and screwdriver fed openings, all of which saves time when connecting and enables the use of motorized screwdrivers.

The devices with spring-loaded terminals can be connected quickly and tightly, and when single-pole blocks are used the command positions can be butt-mounted.

Configuration

Mounting and fixing

The 3SB3 devices can be easily and quickly mounted:

• Actuators or indicator lights are positioned in the opening of the front panel from the front
• Position the holder from the rear
• Tighten the screw on the holder
• Snap on the contact block or the lampholder directly onto the actuator from the back

The holder for the round versions is set to a switchboard thickness of 1 to 4 mm when delivered and is placed in the direction of the arrow ^ 1–4 mm ^ on the actuator/indicator from the back. The fixing screw is located underneath, on the right.

For a switchboard thickness of 3 to 6 mm, the holder is reversed and mounted in the direction of the arrow at ^ 3–6 mm ^ and the fixing screw is located on the upper right. In this case, the fixing screw must be rotated anticlockwise to its limit before mounting the holder.

The control panel depth of 1 to 4 mm can be compensated with the holder for the square version.

When label holders, protective caps or similar accessories are used, the greatest permissible panel thickness must be reduced by wall thickness of the accessory part.

Installation dimensions on front plates

Round version

Square version

The dimension a totals at least 30 mm, but for mushroom pushbuttons and push-pull buttons, the mushroom diameter must be 40 or 60 mm.

The dimension b totals at least 30 mm, but for mushroom pushbuttons and push-pull buttons, the mushroom diameter must be 40 or 60 mm. In addition, the dimensions of the contact blocks must be observed, this results in larger b dimension: Contact blocks and lampholders with screw terminal 45 mm, block contacts with 2 contacts 50 mm.