....thought I would take a minute to discuss a very much overlooked aspect of planetarium operations....saving your computer, audio, and video equipment from harmful fluctuations in AC power. I have been amazed at how often we see systems (even new ones) without proper (or any) power protection. Here are some solutions for power conditioning. These units can even be networked to turn on-off in a properly sequenced and timed order so as to save your components from turn on surges and thumps.
Power line disturbances are real, and they are inevitable. According to Consumer Reports (November, 1994), "One significant surge a day is the norm. High-exposure areas may experience perhaps a hundred smallish spikes a day." Proper protection is essential for costly equipment, even more so if it is frequently moved from location to location. But there is a wide range of differences in the performance available from the protection products available.
Some selected power conditioners provide complete and comprehensive protection from power line-related transient voltages, noise, and wiring faults available. Their many special features are designed specifically to provide maximum protection from the type of hazards faced by delicate computer, digital pro audio and video equipment. They can also reduce and eliminate extraneous buzzes and hums.
What sets the some products apart from other conditioners is the quantity, quality, and configuration of the suppression devices used. Good units use a collection of MOV's, gas discharge tubes, fast-blow fuses, and high voltage inductors and capacitors. This unique combination can safely absorb and dissipate large spikes from nearby lightning strikes and other sources (up to 11,000 amps across any wiring mode -hot-neutral, hot-ground, or neutral-ground), as well as highly attenuate audible high-frequency noise. Precise high-inrush magnetic circuit breakers avoid the false tripping often encountered with large reactive loads like power amps.
An additional feature, Extreme Voltage Shutdown, fights a hazard particularly common in the entertainment industry: wiring faults - for example, accidental connection to 220V. It senses voltages that are so high or low that operation would be impossible (under 80V or over 140V) and shuts the power down before damage can occur. LED status indicators ("Protection OK" and "Ground OK") monitor the integrity of the protection devices and grounding, and report if the protection is compromised. Some units have the familiar slide-out rack lights ...some have an accurate, self-checking AC voltmeter that not only measures normal voltages, but also flashes eye-catching special pattern alerts for off-scale but not extreme conditions (80-90 or 130-140 volts).
One or more conditioning units may be installed in remote locations around the theater (one at video projector, one at console, a couple in equipment room) and this networked system can be turned on remotely via keyswitch via low-voltage 22 guage wiring.Units we install are capable of powering up a rack full of equipment in a 3 or more-step delayed sequence. The sequence is reversed for power-down. One or two duplex outlets are provided for each delay step. A front panel screwdriver adjustment sets the delay time for remote units A locking master switch with a removable key is provided for maximum security. Power conditioners can also contain special circuitry to detect additional wiring faults such as reversed hot and neutral, missing ground or neutral, etc.
Just thought I would mention it. Good units will cost you between $300 and $500.
Sincerely,
Jeff Bowen
Bowen Productions
Indianapolis
OBU Planetarium:
http://www.okbu.edu/academics/natsci/planet/index.htm