Hanging Weight of Vizi Spot LED

The vizi spot led weighs 20 pounds. So you would need at minimum a clamp that can support 20 pounds. I wouldn't use a O clamp. Go for something a step above a o clamp. O clamps i believe are rated at 25 pounds tops.
Sincerely,

p.s. ALWAYS use a safety cable.

Thanks for the information.

The bracket I have will support weights up to 40kg, so should easily cope with the static weight of 9kg. I'll rely on the installer to know which fixings to use to secure the bracket to the wall.

However, the manual says to allow for 10 times the weight - so, do I really need a bracket that can holg 90kg, or do you think my 40kg bracket will be sufficient?

Thanks again.

That is what the safety should be rated for. Reason is if the clamp fails, a safety will have to take to force of the fixture dropping slightly. When steel safety cables display their rating, this 10x gain should already be factored in. The breaking point on a safety is also the clip, as 1/8" stainless steel cable's breaking point is about 1,700 lbs.