AC POWER
Changes naturally require foresight and planning. But when AC power enters the scene, there’s a lot of mystery and unanswered questions. After all, you cannot see or otherwise detect AC power--only the effect of it.
With modern technology though, we can make some sound educated guesses, knowing something about what’s coming down the pike at us. Yet, at this point in time, there may be more uncertainty about future power demands than most any time in the past.
Today’s well thought-out intelligent DSP-based sophisticated monitoring has the potential of shifting the electrician’s job from the work-floor to the office, and eventually distant parts of the church building.
This is due to the constantly changing nature of lighting instruments, audio amplifiers, and the rapid move towards Mass Notification for Campus Security, which not only carries direct power demands, but also backup generators along with their care and feeding.
Today’s well thought-out intelligent DSP-based sophisticated monitoring has the potential of shifting the electrician’s job from the work-floor to the office, and eventually distant parts of the church building.
Installing new power generating plants basically requires a survey of the top soil (for weight bearing) and choosing an appropriate location -- all set forth neatly in the National Electric Code (NEC) book.
But you think about it, and impeccable mechanical stability in electronic and electro-mechanical gear has got to be where it starts. Unstable buildings ... especially in a Seismic zone 7 (SF Bay Area), are throwing good money away and leading to a possible mega-failure. Those who saw the kinetic power of the failed bridge panels during the 1989 earthquake would have little argument with this.
As engineers, we have to consider everything. Your clients' churches may be on anything BUT solid ground, as we’ve seen from the misery of sub-standard structures that have collapsed into virtual nothingness after heavy precipitation, poor soil preparation, and so forth.
THE PRE-PLAN
Why do we even need emergency power? It’s for getting people in and out safely, but also for the Mass Emergency Notification systems that have become critical in spaces where people congregate. To make no mistake, some of these new – almost fashionable demands – have intrinsic value. Others, however, are more political in nature than functional. Nonetheless, some half billion dollars will likely be spent this year and again next to satisfy both real and politically motivated financial maneuvering.
THE PLAN
The first big step is to determine if the building will have a B/U generator at all, or will it be run only on grid power. This is a big decision that can turn into a lot of money for the equipment and engineering, not even including all the associated costs of construction permitting, operating permits, air quality inspections, safety inspections, obtaining Air Quality Control permits, seismic inspections, fuel safety, H-3 fire resistance ... the list seems to go on forever.
MOVING ON
The NEXT Step is in planning – and this is a big one -- how the emergency power will be deployed. The Board of Directors will wish to make a major decision about this. The choices made here will affect almost everything both inside and outside the power domain. The questions are essentially simple, but that doesn’t necessarily mean the answers are.
Will the system be 100% self-supported with centralized battery backup (campus-wide or building wide), or will it rely on finding little Johnny’s arrest record before he can do any more mayhem, avoiding a complicated hunt for access keys and personnel approval?
For help with the hardware side of things, large-scale suppliers such as Cumins and CAT are more than just sales companies. They are genuine engineering partners. It’s no simple thing to phase-lock-loop thousands of points of moving mass so that nothing gets damaged mechanically, or out of sync electrically, which can be equally damaging. A Cummins rig is designed to do this with the grid, as is a CAT rig with the appropriate external equipment.
MULTIPLE BUILDINGS
Things can get quite complicated when multiple locations are brought together. The engineering goes beyond the scope of this brief report. However, here are some critical areas of importance to keep in mind on your church projects.
In all walks of life there is a need for every imaginable form of power consumption, with lighting usually being the largest consumer. Lighting is limited only by the imagination of the lighting designer and the manufacturers that make the equipment (and, of course, the budget). The really large shows use a great deal of power, but with today’s LED-based instruments, power demands have been reduced on a huge scale.
AUDIO
The same goes for audio. You see ads for huge power amplifiers of 10,000 watts and more, but the reality is that the power demand in a given audio system is so short on peaks that the 10,000 watts can be scaled down to about 1/10th without compromising the system’s integrity. Unlike [lighting], audio is of such a short, transient nature, it stresses the grid and any other gear so lightly, it’s almost a non-factor.
CLOSING THOUGHTS
The word this year (and for the foreseeable future) is MNESF, Mass Notification Systems. Sadly, domestic conflict has made it essential not to ignore MNESF and every other form of available protection.
As the world gets more complicated and violence would appear to play an ever increasing role in our lives, many opportunities will open while others will close. There’s still much to learn about Mass Notification, Back/Up Power, and a lot more in the same category. Literally, the book is still being written, and none too soon. Large generator installations can take months to years before they are ready to go on-line.
