BLOW 3905# Double On-On Rotary Switch, 3A 250V, model 3905#

BLOW 3905# Double On-On Rotary Switch is a compact mechanical selector designed for manual switching between two circuits or positions. Rated for 3A at 250V, this rotary switch provides a simple, low-current switching solution for control panels, instruments, and small appliances where a reliable two-position selector is required. The switch features a double pole configuration allowing simultaneous switching of two circuits with a single rotary action.

Advantages

The switch offers a compact footprint and mechanical robustness suitable for frequent manual operation. Its double-pole on-on design enables synchronized switching of two separate circuits, reducing wiring complexity and saving panel space. The 3A/250V rating is appropriate for low-current control and signal applications, while the rotary actuator provides clear tactile feedback for position selection.

Suitable for

• Control panels and instrumentation requiring two-position selection
• Small appliances and consumer electronics with low-current switching needs
• Audio or signal routing where manual selection between two paths is needed
• Prototyping and DIY electronics projects that require a compact rotary selector

Key specifications

• Switch type: Double pole, two-position (On–On) rotary selector
• Rated current: 3 A
• Rated voltage: 250 V (AC)
• Actuation: Manual rotary knob with defined stop positions
• Typical applications: Low-current control, signal switching, panel mounting

How to use

Mount the switch in an appropriately sized panel cutout and secure it using the built-in fastening method. Wire each pole according to the desired circuit paths, ensuring power is disconnected before making connections. Rotate the actuator to select the desired output path; the double pole design will change both circuits simultaneously. Verify connections and operation at low power before placing the switch into full service.

Usage recommendations

Use the switch within its rated limits of 3A and 250V and avoid inductive loads or high inrush currents without additional protection. For long-term reliability, avoid excessive mechanical force on the actuator and perform periodic inspections of contacts and mounting if used in harsh environments.