Lasizas Stern Light

[SteveIOW]

Have just purchased this low profile LED stern navigation light. Fitting instructions do not state the orientation, ie should the fixing screws be side by side or one above the other. Pretty sure only one way will give the required 135 degree horizontal beam.
Anyone know which way it should be fitted please?

 

[Dellquay13]

I guess the fresnel lens should be vertical? Try powering it up?

 

[John 32i]

Ours is vertical.

 

[lustyd]

It’d have to be vertical to make the correct angle.
Check the manual thoroughly as many LED fittings start blinking after a couple of years to indicate end of life and required replacement. This is intentional.

 

[VicS]

Have just purchased this low profile LED stern navigation light. Fitting instructions do not state the orientation, ie should the fixing screws be side by side or one above the other. Pretty sure only one way will give the required 135 degree horizontal beam.
Anyone know which way it should be fitted please?

ITYWF that the fixing screws should be top and bottom so that the elements of the Fresnel lens are horizontal to concentrate the light beam into a wide horizontal beam with little light escaping skywards or towards the water.
I'm a bit doubtful about it having good cut off angles at 135° but maybe it'll be ok.

 

[lustyd]

The metal is the cut off, either side of the lenses which are recessed. The light is flat so the lenses are there to scatter light sideways and therefore need to be vertical.

 

[lustyd]

Hmm, searching for a manual it seems it might be a light for sterns, rather than a stern light.
LED Marine Boat Yacht Transom Chrome Anchor Stern Light White Round 2835-SMD 12V

 

[LittleSister]

. . . The light is flat so the lenses are there to scatter light sideways and therefore need to be vertical.

The point of fresnel lenses is specifically to not scatter light, but to concentrate the beam in a single direction. Typically used to focus light from a point source along a parallel beam, instead of continuing to splay out in all directions.

I believe the fresnel sections should run horizontal - i.e. be at the top and bottom of the fitted lamp (with screws also at its top and bottom), to focus the light around the horizontal and not waste it illuminating the sky or the sea, and that the inward angled section of the metal cover will form the required 135 degree angled cut-off.

You could check by connecting the lamp to a 12v battery, and along one axis the bean should should spread pretty evenly exactly 135 degrees only (and not visible at all beyond that), and along the other axis mainly focus around the centreline, but some scatter either side not critical.

Here's examples of other nav lights, clearly showing the fresnel sections running horizontally:

(above Osculati, below Lalizas)


The advert says it is Lalizas, but I notice this lamp is not listed on the Lalizas website, and that those navigation lights which are listed there each have a drawing showing how it is mounted.

 

[Malish]

ask the supplier?

 

[lustyd]

The advert says it is Lalizas, but I notice this lamp is not listed on the Lalizas website

Yes that was what eventually led me to the link which suggests it’s more of a transom light with a 120 degree pattern so which way up is a matter of pure aesthetics since its not a nav light

 

[S04]

The listing for the one in the original post says that one has a 135° angle though.

 

[lustyd]

The listing for the one in the original post says that one has a 135° angle though.

Yes it did, but a little research suggests it’s actually a decorative transom light for motor boats. Unfortunately “stern light” can mean many things.
The 120 degrees I found was on the actual instruction sheet on the listing I found, the only one that had further information that I could see