The Dilemma of the Red Projected Stop Sign

Why do some projected stop signs cost more than others?

Some months ago, I visited a new customer who wanted to project a stop sign onto their floor whenever a forklift approached. The goal was to prevent pedestrians from walking into the path of an oncoming FLT.

The customer had done their research well. They knew that a typical LED floor projector costs between £700 and £1,000, plus installation and switchgear.

However, when I later reviewed the proposal with them, I saw a price of £5,200 per projector - far beyond the expected range. The customer was understandably shocked. So, what went wrong?

Are LED Projected Floor Markings really only £1,000 each?

Most projected floor markings do fall within the £700–£1,000 range—but only if they meet certain conditions. The final cost can vary depending on:

• LUX Level within your factory
• Floor to ceiling height
• The colour of your projection

If the LUX level is above say 400lux, then a brighter projector is needed to combat the existing light, otherwise the projection will not be too clear.

Projectors up to 100W work for most environments. When the projectors get bigger than this, we start requiring active cooling, bigger transformers and of course, more powerful light sources. 

Floor-to-ceiling heights also make a difference to the power of the projector required but again, up to 13metres we can normally use a 100W projector. But as we get outside of this, especially in combination with brighter lux levels, we need more powerful projectors.

The colour of your projection also makes a massive difference. Just like a pair of sunglasses, the projected image is really just a filter on the end of your LED light source.

To project a bright red stop sign, we use a coloured lens known as a 'GOBO', but red is the hardest colour to project because it filters out over 90% of the light!

What are the best options for clear projected warnings?

There are two excellent options for you if you want a vivid projection to warn or stop pedestrians/traffic, change the colour or have no filter. Change the colour, you don't have to use red.

Some colours such as yellow, only filter out around 15% of the light; this means that you can afford to use a lower-power projector and still get a clear message across.

Or don't filter it at all. You read that correct. Rather than projecting a white light and channelling it through a red lens, use a red light source.

Progtech manufacture projector light sources using a coloured LEDs. A coloured LED light sources costs the same as a white light source and is significantly brighter per watt.

What are the downsides of each option?

With both options, there are drawbacks. Using a yellow lens or 'Gobo' will not have the same impact as a red projection. However, it is a great option where the conditions do not suit using a red lens.

With a coloured light source, this will always give you maximum efficiency and use of a projected light source. However, this means using an aluminium gobo or lens - an aluminium gobo is cut on a CNC machine rather than printed which means you could end up with 'spigots' to hold the letters together. 

Which projection option ss best for you?

If you want maximum efficiency and clarity, a coloured LED projector is the best option.

Request a trial at your site to see the difference for yourself.