Rewired stage lights

[sleah]

I'm puzzled as to why the lamps blew!

[timsabre]

I'm puzzled as to why the lamps blew!

 

Could be coincidence, sliding the focus knob banging the filament about

[Hilary Watts]

Is it possible that the lamps have not actually blown but simply gone out as a result of a fuse blowing or circuit breaker tripping following a short-circuit?

[adam2]

650W @ 230v = approx 3A = 0.5mm2 cable.

But then we get into the rulze and find even though its a 650w load we may still need to use a cable rated for 10A or maybe more depending what the size of protective device is, or in regs speak, Ib ≤ In ≤ Iz

 

In general, the cable fitted to an appliance (including a theatre lantern) may be sized according to the load, not the circuit rating, but with the caveat that it must be at least 0.75mm.

 

Research has shown that 0.75mm flex can be protected against short circuit by a fuse or circuit breaker of up to 16 or even 20 amps. So a theatre lantern with a 15 amp plug does not need 1.5mm cable, but does in practice need at least 0.75mm.

 

If the dimmers have 10 amp fuses, as is very common, then 0.5mm flex is safe in theory but it would be very poor practice to use less than 0.75mm. What if the lantern is used in another venue on a non dimmed circuit on a 13/15/16/20 amp circuit ? In my view any standard theatre lantern should be safe to use on any properly wired outlet in any venue, and should NOT be wired in a way that is only safe on the dimmers in its own venue.

 

Many new lanterns come with 0.75mm or 1.0mm flex.

 

 

 

 

 

 

 

[Jivemaster]

Competence is harder to manage in an am dram establishment. In my am dram days the technical work was done by three members who were all employed by the local electrical shop/company all of them did installs some of them mended (valve!) TVs. Now it's increasingly (with litigation, regulation and insurance) necessary to have suitably competent people around, and if they don't volunteer as members then you have to pay them as contractors.

 

Your technical crew should be able to demonstrate perfectly wired plugs at all times, those that can, OK! Those that cannot do NOT do electrics without supervision. Having two crew to do a job means that the work should be peer assessed and perhaps actually tested, it also discourages lone working and possibly lone work at height.

 

Add to the mix that lanterns get HOT and usually need special heat resistant cable, rewiring lanterns needs some prior thought, careful execution, and proper test and inspection, which it seems they didn't get.