Isolation Switch Advioce Please

[the_constructor]

In my bathroom, inherited from previous occupiers, I have a low voltage timer fan:

The timer is up in the loft.

In the loft is a junction box for the bathroom light and the timer for the fan above is wired up as follows.

Constant live from live input to junction box. Switched live from return on light switch Constant neutral from neutral input to junction box

thus, when light is switched on and off, the fan keeps going for a set period of time.

What I would like to do is electrically isolate the timer from the lighting circuit, for safety.

Any ideas please as to how or what I should use to do this.

Thanks in advance

[Andrew Gabriel]

3-pole fan isolators are standardly available for this purpose. They look like a light switch with very wide rocker. The fan should have the ability to be isolated anyway, as this is required for all accessories with powered moving parts. The switch needs to be positioned such that it is under the direct supervision of anyone maintaining the fan, or it must be able to be locked in the off position (the MK one can using a separately available locking bar which goes into tiny holes on the edges of the rocker).