Cable With Caution

[GoboMan]

Today I was doing a light hang in a venue I have never been to before, and I discovered this in the catwalk...

This is after I had to use a screwdriver to pry the cable off of the instrument and peel it away. It was completely fused to the lamp housing. I have decided I will NOT be using this particular dimmer during this production.

Afterwards, I discovered three more dimmer cables that were not unusable, but definitely showed signs of the start of the melting process.


** Remember to watch where you run those cables! **

 

[avkid]

How do people not notice these things?

 

[josh88]

On a related note also watch wear you're putting things down. I had to catch myself tonight and NOT sit the ball of heat that I was taking down (known as a S4 Par) on the marley the ballet company just laid out on my floor. Probably wouldn't have been serious, but also probably wouldn't have been great either for a similar reason.

 

[gafftapegreenia]

Is that, in fact, 12/3 SOOW?

 

[Footer]

One of the various reasons pigtails can be a pain. One reason I tie them off to the bottom pipe of the electric unless they are being used for their length.

 

[GoboMan]

Is that, in fact, 12/3 SOOW?

Indeed it is, with Twist-Lock!

 

[lj274mvp]

I've seen this happen before in a new venue I was working in. Except it was the main dmx line to the dimmers that had melted to the fixture.

 

[zmb]

How crunchy did the cable get? Strand SLs will do this to cable without warning and have the outer insulation melt around the heat-diffusing fins, thankfully just to extensions so far and not pigtails.

 

[rm2011]

How crunchy did the cable get? Strand SLs will do this to cable without warning and have the outer insulation melt around the heat-diffusing fins, thankfully just to extensions so far and not pigtails.

Indeed they will. Strangely I'VE never seen it happen with a source 4.

Sent from my Nexus 7 using Tapatalk 4 Beta

 

[gafftapegreenia]

This is very interesting. As Ive seen cables laid across both Source 4 and 360Qs but not exhibit melting.

 

[STEVETERRY]

Guys, please, get serious.

Type SO and derivatives which have a temperature rating of 60C or 90C cannot ever be allowed to come in contact with tungsten fixture bodies. It is a dead certainty that bad things will happen if they do.

That is one reason why, in the theatre, we have an NEC requirement for "qualified personnel".

ST

 

[JD]

Type ST cable? I would think SO would have burned as compared to that oozing melt. Never underestimate how hot a fixture can get. (Thus the nature of the cable whips going into the fixture.)

 

[rm2011]

Guys, please, get serious.

Type SO and derivatives which have a temperature rating of 60C or 90C cannot ever be allowed to come in contact with tungsten fixture bodies. It is a dead certainty that bad things will happen if they do.

That is one reason why, in the theatre, we have an NEC requirement for "qualified personnel".

ST

This is true, and I don't think any of us were condoning the practice but saying that we've FOUND it before. At a dinner theatre I work at there is cable strung all over the place because they don't want to pay for the labor hours to have everything struck and rehung between shows (everything is dead hung and circuits are mostly on the end of the pipes). I quite often find cable laying on top of fixtures and have never found melted cable from a source 4. SL's are a different story.

Sent from my Nexus 7 using Tapatalk 2

 

[Les]

I've seen the Y section of two-fers more or less permanently adhered to the body of an SL before. :/

 

[Esoteric]

While we are at it, don't lay cables on a catwalk.

 

[masterelectrician2112]

While we are at it, don't lay cables on a catwalk.

Or if you do, as I have to in one space at my university, secure the cable with tie line and or gaff tape. We are told to tie the cable to the building structure where we can every few feet to keep it against the extreme sides of the catwalks. But definitely don't leave cables laying unsecured in the middle of the catwalk. That's asking for trouble.

 

[GoboMan]

Excellent point. Another thing I noticed later on the same day that I found the melted cable, was that whoever was there before me decided to "steal" a dimmer from stage cat #1 to power an instrument that was hanging on stage cat #2, and the dimmer cable was hanging in the air about 6" off the ground across the width of the cat #1 as it made its way to cat #2. And only having less-than-ample work light around me, it was a trip accident waiting to happen. I took the liberty to re-assign that instrument to another dimmer.