DMX Generator

[sleah]

Hang on.

 

Surely the approved, non-modifyable emergency lighting is adequate for building evacuation (otherwise is would not pass muster) so wouldn't the fact the coloured lights go off indicate 'party over folks'?

 

If the existing emergeny lighting system doesn't provide adequate light, then surely it isn't fit for purpose and that needs looking at??? :blink:

[Bruff]

Bruff, either you or I have misunderstood :)

 

The only mains into the fittings is the secondary feed, so can't be used to sense mains failure.

 

I was suggesting the the mains powered relay is in the feed to the wireless DMX transmitter, which presumably is not adjacent to the lights...? And is powered from wherever the lights get their mains from. So if the mains fails to the lights generally, then the relay opens, and the UPS powered lights change from colour to o/w.

 

Spot on.

 

Also in the mains circuit feeding the wireless DMX transmitter will be a relay fed by a fire alarm interface, so the o/w state is activated by the fire alarm.

 

The only mains into the fittings is the secondary feed, so can't be used to sense mains failure.

 

??

Surely the secondary feed would go off in the event of mains fail... that's how emergency lights work.

 

How do you know that your "pilot DMX" would go away in the event of an emergency?

 

The secondary feed comes from a central battery via a static inverter - it does not go off in the event of mains failure. Not for at least 3 hours, anyway.

 

The pilot DMX would go away in the event of a mains failure (or a fire alarm activation - see recent post)because the DMX transmitter would be mains-fed.

[ImagineerTom]

I'm pretty sure your insurers, the H&S and your local fire officer would want some input into the design of (and independent testing once built) anything you create that controls emergency lighting - even a simple relay that "fails" open if the power dies would need to be of a suitably durable, dependable grade and be mounted in such a way that the heat/smoke/fumes from a fire wouldn't interrupt its operation.

 

As a concept it's a cool idea but there is a reason why emergency lights and control systems are expensive to buy and install; there's a LOT of regulations and requirements that aren't immediately obvious.

[JFeenstra]

What about using a fixture that has the ability to recall a static predetermined scene when DMX is lost? That would negate the need for a triggered relay, and you could set the scene to recall something full on open white when the DMX feed disappears.