PRG Production Tips - #4 - "POWER: Trust But Verify"
by Chris Conti
Power, trust but verify. That’s my mantra when it comes to power. Without electricity, a modern show is no different than a play during the time of ancient Greece. Power is everything. It has enabled us to up-our-game more than just a little bit since 600 B.C. So, when we load-in a show it’s imperative that we do everything possible to ensure our shows do not end up as Greek Tragedies.
Many of the power distro racks that we utilize today for our lighting, audio, video, and scenic systems have all kinds of built-in circuit protections and distribution capabilities. But most crucially of all, these distro racks have meter bars. A simple read-out that tells us voltage on each leg as well as current draw. With a look at the meter bar you can see if your power is doing what it’s supposed to be doing. Having said all that, I trust meter bars about as much I trust that I can lift a rack up by myself and throw it across a stage. That’s why I always verify that my meter bars are reading true regardless of the manufacturer. I carry an all-in-one multi-meter that enables me to measure a bunch of different things. It has a non-contact voltage detector to very if a feeder cable is energized or not. With the meter, I can also measure the voltages, phase to neutral, and phase to phase on the rack before I energize it. I do this to double check that the meter bar is indeed accurate and that it wasn’t damaged in transit. Once energized and under load I can use my meter to also double check the amperage readings on the meter bar. I check the amperage on each phase as well as the neutral. Again, this to double check that the meter bar is displaying accurate information. I have also recently expanded my diagnostic tools to include a Thermal Imaging Camera. With a quick glance, I can instantly see if a cable or a rack is getting too hot indicating that a potential problem is brewing. This probably seems a bit excessive and even paranoid but unfortunately, I have done a few shows over the years where I have had problems that have led me here. I indeed have had meters damaged in transit, voltage spikes that have fried the meter bar, phases inadvertently dropped, feeder cables not properly tied in, current over loads, voltage overloads, generators out-putting improper voltage, and I even have had a distro and a transformer short out and blow up! In those particular instances, I am very fortunate that no one was injured and that there was minimal equipment damage. So, when it comes to power I am cautious. I double check everything, and verify that it is indeed operating correctly and displaying the correct information. You may want to consider doing the same so that your show doesn’t don’t end up like a Greek Tragedy. Remember, trust … but verify.