Latch Type Solenoid Valve :

WORKING PRINCIPLE :

In Fluid Control applications where sudden/ momentary loss of power which can result in safety issues, create a major shut down, affecting up time and in applications where continuous power consumption affects the life of power supply, Latch coil solenoid valves offer the ideal solution.

Using a Magnetic Latching principle, the Latch type solenoid has two coils with opposing windings and a permanent magnet.The solenoid has three terminals, for latching (energizing) and De-latching (de- energizing).

On energizing the Latch coil (either by a pulse of power or continuous power), plunger is pulled and latched magnetically.

The Latch solenoid is designed for continuous energization in case the application demands. Loss of power or switching off the Latch coil will not change the valve position. Momentary pulse to the De-latch coil will de-energize the solenoid valve.Optionally a manual override can also manually Latch/manually De-latch the Solenoid valve.

The Latch type Solenoid system has been designed in a manner to facilitate conversion of single solenoid valve to a stay put the device i.e. on power failure to retain last position. However, Manual override feature on single solenoid valve (if installed) cannot be used to de-energize the Solenoid valve manually. These valve have to be de-enegized electrically.

For AC power supply, a full bridge rectifier is used to convert AC into DC internally.

The latch solenoid can be used to convert any of the rotex single solenoid valve to work as impulse operated for such valve.
The manual override will only latch the valve has to be delatched electrically.

SOLENOID LC

Solenoid has inbuilt two windings and a permanent magnet. Both the windings have inbuilt rectifier. Its one end is common and providing supply to latch coil to pull plunger upward. The magnet keeps plunger pulled and even if supplies to latch coil is removed. The plunger resets when DL coil is momentarily energised.

RC : Rectifier bridge
P : Permanent magnet
LC : Terminal Latch
COM : Common
DL : Delatch terminal

The solenoid consists of single winding and a permanent magnet. The magnet is not strong enough to pull the plunger of its own however it is strong enough to retain the plunger in position once actuated.

The current passed the coil generates magnetic force which assists the magnetic force of the magnet. Due to this plunger gets actuated. Now, due to magnet plunger remains actuated even when power supply to the solenoid is removed.

The plunger can be deactivated by passing current in the coil in reversed direction.

Usually DC powered solenoid can only be offered with this arrangement.


FEATURES :
Continuous duty

Suitable to operate in high temperature zone (near boiler).

Ex d version available

Valves are provided with Manual override for latch.

Most valves can be latched manually by turning knob anticlockwise
and delatched by turning knob clockwise.

In normal condition Manual Override knob has to be maintained in horizontal position

Wide range of 2, 3, 5 port Direct/ Pilot operated Valves can be supplied

Two wire latch coil can also be supplied (Require reversal of
power supply for changing valve Position)

Ambient / Fluid Temperature :  - 20°C to 80°C

Media : Air , Inert , Gases , Water , Oil

Application :
2 , 3 or 5 port single solenoid valve required to retain position in case of power failure.