Magnetically held rotary switch - flitepal.com

Magnetically held rotary switchin the style of the Boeing 737 engine start switches

1 Specifications and dimensions are subject to change. Please refer to latest datasheet for most current specifications for this product.

FlitePal Ltd. • www.flitepal.comRevision date 01.04.2021

Description anD features

Positions 1, 3 and 4 are isolated from position 2 by the means of a lock over the vertical axis of the switch actuator. The actuator has to be pushed in to unlock (approx. 4.5mm, maximum travel 6mm), only then positions 1, 3 and 4 can be selected. This locking feature is spring loaded - the switch actuator returns to locked position when released by the operator and the current switch position is 2.

Position 1 is spring loaded to return to position 2 when selected and the switch is released. The spring return position can be held in place by a holding solenoid, until the power to the solenoid is cut and the switch returns to position 2.

Those features completely replicate the behaviour of the Boeing 737 engine start switches.

• Four-position rotary switch• Isolated positions • Magnetically held momentary position• Cast body• Carbon steel bushing• Easy setup and operation

application

Hobby electronics, DIY projects, home-built flightdeck

This switch is not suitable for commercial or industrial application




Dimensions

All dimensions are shown in mm. Please allow 1mm tolerance to the overall dimensions.




specifications

Rated power 0.3AMax. operation voltage 125V ACContact resistance - initial performance 50mΩ Max.Contact resistance - after lifetime 200mΩ Max.Insulation Resistance 100MΩ Min. at DC 500VWithstand Voltage 1 minute at: AC 500VNumber of poles 1Number of positions 4Terminals PCB thru-hole (circuit board optional)Angle of throw 30 degreesManual soldering Max. 3s at 350 degrees COperation temperature 0-40 degrees CRotation life 10 000 cycles min.

HolDing function

The spring loaded position 1 of the switch can be held in place by an electrically powered holding solenoid. The holding function control consists of two separate circuits:

• Holding solenoid power supply - powers the holding solenoid. Draws up to 60mA of current when closed. Has an independent power supply and requires 12V DC

• Holding solenoid switch circuit - transistor switch circuit that turns on and off the power supply to the holding solenoid. When the holding solenoid is powered, the momentary position of the switch is maintained in place. When the power to the holding solenoid is switched off, the rotary switch returns automatically to position 2. The power to the switch circuit has to be uninterrupted. Consumption of the switch circuit is up to 10mA and requires 3.3-12V DC

The holding function control is designed in such a way to allow a less powerful source such as a single board computer to switch the holding solenoid on and off.

The holding solenoid produces some heat when powered, which is normal. A thermal switch protects the device from overheating by cutting the power when the temperature reaches above 65 degrees C.

Please follow the instruction below when powering the holding solenoid.

Rotary switch

Holding solenoid

Supply voltage 12V DCPower consumption 06mA max

Switching circuit

Supply voltage 3.3V - 12V DCRequired supply current up to 10mA




(common terminal)

circuitry of rotary switcH recommenDeD panel cutout

The switch is designed for panel mounting by the means of a carbon steel M12x0.75 threaded bushing. Maximum panel thickness is 4mm. There is no minimum panel thickness.

HolDing function setup

A 4 pin wire-to-board connector is provided with wire leads to ease installation. The connector plugs in to the 4-circuit DIP header on the solenoid control circuit board. Connect each wire lead as follows:

• +12V (yellow wire lead) - Connect to the plus of solenoid power supply. Required voltage is 12V DC.

• ARM (red wire lead)- Connect to the plus of the arming signal that activates the solenoid. 3.3V-12V is accept-able (DC only).

• GND (2x) (black and blue wire leads) - Connect to the ground of power supply and switch circuit. If the power supply and switch circuit share the same ground, then only one ground needs to be connected. Blue wire lead connects to solenoid power supply and the black wire lead connects to the arming circuit.

Solenoid control circuit board (displayed before assembly)




Rotary knob in the style of Boeing 737 (optional, not included)

Painted in three colours to replicate black and white index line

Jumper (included)

Please use if de-rating solenoid power supply voltage or as instructed by manufacturer. Install at R BYPASS header

HarDware

Hex nut and lock washer (included)

Lock washer to be installed between switch and panel (to the rear side of panel as opposed to the front)

4P Wire-to-board connector (included)

Used to power the holding solenoid and the arming circuit

5P Wire-to-board connector and rotary switch PCB (optional, not included)

For ease of installation, switch terminals are brought to wires; circuit board soldered to rotary switch




caution

Please be advised, that:

• Setup/electrical connection of this equipment requires knowledge of DC electricity. Do not attempt to setup and use if you don’t have understanding of this datasheet

• Children should not use this product unsupervised

• Indoor use only. Not designed to withstand extreme ambient conditions. Keep away from water and high humidity

• DC equipment only! Do not connect to AC current or to excessive voltage due to risk of fire!

• Using this equipment against the specification of this datasheet with regard to Polarity, Supply Voltage, Ambient temperature can result in parts failure, circuit board failure and/or holding solenoid failure

• The equipment has been tested to withstand ambient temperature of 50 degrees C, however, the recommended maximum ambient temperature for operation and storage is up to 40 degrees C, due to reduced thermal tolerance of some of the plastic parts. Operation at ambient temperature at and above 50 degrees C can result in equipment damage

• Warranty void if listed precautions and datasheet instructions are not followed, or if the switch is disassembled

proDuct care

• If cleaning is required, use a damp soft cloth with water or mild detergent

• Use only plastic safe lubricants to lubricate moving parts. Lubricant or grease based on silicone is recommended

Documents

Magnetically held rotary switch - flitepal.com