Please see below some of our frequently asked questions regarding our solenoid and switch ranges. For further assistance email enquiries@nsfcontrols.co.uk or call 01535 661144

A typical solenoid consists of the following main elements: a cyclindrical coil, a steel or iron frame or shell, a steel or iron plunger and optionally, a stationary magnetic pole/travel stop. A magnetic field is generated within the solenoid by passing electrical current through the coil. The frame or shell surround the coil, providing a flux path. In effect, it focuses the magnetic field produced by the coil. The plunger, being made of a highly magnetic material, reacts to the magnetic field by attempting to move to the centre of the coil. The plunger will travel to the centred position unless stopped by a load which exceeds the solenoids force capability, or the plunger contacts the stationary pole/travel stop. The force generated by a solenoid is dependent upon the current flowing through the coil windings.

Maximum solenoid life is achieved when the pull force required coincides as nearly as possible with the force generated by the solenoid. Solenoids which develop substantially more force than is required are subject to excessive hammering which eventually may cause mechanical failure. To improve mechanical life, the load must be in line with the plunger and side loads must be kept to a minimum. Mechanical life in DC solenoids will be increased with the addition of an anti-bottoming feature. There will be a slight reduction in force caused by an internal air gap when an anti-bottoming feature is included.

The following information should be determined to correctly choose a solenoid.

  • What is the linear movement needed?
  • How much force is required to perform the operation?
  • What is the space limitation for the solenoid?
  • What is the duty cycle of the solenoid?
  • What is the operating temperature range?
  • Are there any special industrial environmental concerns?
  • Is there need for additional circuit protection?
  • What size lead wire and length of lead is required?

Typical applications:

Pull – Pinch – Push – Dispense – Lock – Latch – Select – Reject – Index – Divert – Kick – Hold – Release – Eject –- Position

A section (or deck or wafer) is what contacts are mounted on.

A shorting contact is also known as “make before break” and describes the action of the contact as you select your switch positions. The switch will momentarily short position 1 and 2 together when you rotate from position 1 over to position 2. A non-shorting contact is also known as “break before make”. The connection is momentarily broken when you rotate from position 1 over to position 2.

An index angle is the number of degrees between each position.

Gold plating contacts should be used when your product needs a longer shelf life. Also if the switch will not be actuated for a long period of time after installation we recommend the use of gold plating.