Electrics DOs and DON'TS –
Hanging and Striking Lighting Fixtures

Although it is usually not, at the professional level, the job of the lighting designer to hang and focus lighting fixtures, as a student and a young professional you will probably at some point have to participate in hanging and focusing your own plots, or those of others. This is the basic procedure.

Do Don't
In college, basic tools are often furnished by the theatre, but in a professional situation, this is less likely to be the case. At a minimum, you should bring the following:

  • A 6"-8" adjustable crescent wrench, or other tool (or combination of tools) that can handle the various sizes of bolts and screws found on lighting fixtures.

  • A multitool, or:
    • A flat-blade screwdriver.
    • A Philips-head screwdriver.

    The multitool, of course, will also have other useful tools such as knife blades and files.





There is rarely need for a wrench bigger than 8", and the increased leverage provided by such larger tools often leads to over-tightened (and bent) pipe bolts.
Hang every light using the same steps, in the same order, every time. This helps insure nothing is missed. Systems make things safer.  
Visually inspect every fixture before you hang it, and remove from service any fixture that may be unsafe or questionable, until inspected and repaired by a competent person.  
Hang every C-clamp on a given pipe facing the same direction (It makes the pipe easier to work on).  
Leave enough slack cable so that the fixture may be focused (If the cable is too tight, it puts unnecessary strain on the connectors and wastes the time required to correct it). A good rule of thumb is to tie the female connector to the pipe within 6" of the C-clamp.  
After every fixture on the entire hanging position has been hung and tested, tie excess cable neatly to the pipe with tie line. Don't wrap cable around pipe (It puts kinks in the cable and weakens the insulation, eventually causing short circuits or broken connections).
Tighten C-clamps finger-tight and then ¼ or ½ turn with a wrench. Tighten all other C-Clamp bolts (the pan bolt and the yoke bolt); it is far easier to do this while standing on the deck (assuming you're working in a theatre with a fly system) than in the air during a focus call. Don't over tighten – it bends the bolt and weakens the clamp, creating a safety hazard.
Attach safety cables to all fixtures.  
Spread pins as needed to ensure that all connections are tight. Don't rely on tape, tie-line, or rubber bands to keep cables connected (Loose connections will arc. At the very least, this causes deterioration of the connector; it could cause a fire). This applies to all connectors, including twistlocks. Twistlocks guarantee a mechanical connection, but they do not guarantee a good electrical connection.
Make sure that all electrics linesets are properly balanced.  
Make sure that all cabling along the floor is safely dressed and taped (and spiked, if necessary for safety). If possible (when running cables on the floor is unavoidable), run them in recessed tracks so that rolling scenery can cross without damaging the cables. Don't run cables along the floor if it's at all possible to run them overhead.
Fly all electrics linesets above head height before leaving for the day. Don’t ever leave wrenches, gel frames, gobos or other loose gear on any flown electrics. Even if it's "just for a minute", eventually someone will fly out an electric with your tools still on it, and those tools can fall and seriously injure someone.
Store all electrics tools and equipment neatly and safely before leaving. Make sure to check your pockets before leaving the building. Tools sitting on your dresser at home are of no use to you when you're in the theatre the next day.  
Repair broken equipment immediately. Report anything which cannot be immediately repaired to the master electrician. If you cannot find the master electrician, clearly label the equipment, describing the problem. Don't leave equipment in a non-functional condition.
Always work safely. For more on this, see the section on "Safety". Don't ever work barefoot or in sandals, or any other open-toed (or open-heeled) shoe; flip-flops and crocs are not for the theatre. Likewise, don't wear dangly jewelry unless you want it, and the body parts to which it's attached, to snag and fly out with a moving batten.

If you encounter an electrical problem you don't completely understand, don't play around with it. Call in a professional and do not try to fix it on your own, even if this means a show has to wait.

Don't work with live equipment unless you have someone sitting at the console alert to turn things off.

Do use appropriate lengths of cable to circuit instruments. Don’t use multiple short cables when longer cables are available: in multiplies the number of potential problems you may need to trouble-shoot significantly, and you may need those short cables for other purposes.

Don’t remove ties from the cables if they are there to keep lengths of cable tied up for easy access – if you find a cable without a tie, add one to it.

Follow this procedure when hanging lights:

  1. Place the C-Clamp over the pipe and tighten it finger-tight.
  2. Attach the safety cable.
  3. Tighten the C-Clamp ¼ to ½ turn with a wrench.
  4. If the fixture is an ellipsoidal reflector spotlight, pull out all the shutters.
  5. Plug in the fixture.
  6. Write the circuit number in the appropriate place on the plot and/or paperwork, or report it to the master electrician.
  7. When hanging units on catwalks, dress cables off the walking surfaces or on one side of the catwalk. Avoid stringing cables across the catwalks if possible; run cable under them where possible. Secure loose cables to the catwalks as you might to a batten, with a bow, so that they might easily be removed when the show is struck.
  8. Give the fixture a "shoulder shake": Lightly grab the "shoulder" of the unit's yoke and wiggle it watching the top jaw of the C-clamp where it rests on the top of the pipe. If there is any movement between the clamp and pipe, the clamp is not tight enough. Give the bolt another ¼ turn. Repeat as necessary. (Courtesy of Larry Stahl, Technical Director, Gibson Center for the Arts, Washington College, Chestertown, MD)
 

Don't put the C-Clamp over any cabling which may be running along the pipe.


Don't leave shutters in after hanging a fixture – if the lamp is turned on, the shutters will warp, burn, and eventually look like this:

Don't use knots when tying cables to the pipes.

Follow this procedure when striking lights:

  1. If the fixture is an ellipsoidal reflector spotlight, push the shutters all the way in. This protects them from being bent.
  2. Unplug the fixture. Secure the cable, by wrapping it around the fixture, so that it will not catch on anything as the fixture is moved.
  3. Slightly loosen the C-Clamp so that it is just finger tight.
  4. Release the safety cable and secure it.
  5. Loosen the C-Clamp further and remove the fixture from the pipe. Store it in the appropriate place.
  6. Return all cables, templates, template holders, gels, gel frames and other accessories to their designated storage locations.
 


Don't leave shutters out; they will catch on adjacent objects, and get bent.




Don't leave the fixture unsecured on a grid or catwalk where it can fall and injure people below. Likewise, don't leave it on the floor where it becomes a trip hazard for you or others.