Preventing Power Emergencies
It’s easy to put off capital investments in the power infrastructure. But facility executives who find that those expenditures are being delayed year after year should consider what happened at one hospital. There, other priorities cropped up each year that made maintaining the physical plant seem unimportant. For example, replacement of an old generator was put off for three years in a row. Finally, the generator failed during its monthly testing. And the generator was so old that the parts to fix the engine were no longer available.
To maintain a hospital license, the organization rented and temporarily wired in a generator. The hospital was forced to pay a substantial daily rental fee for four weeks before a new generator was delivered. To get the replacement generator delivered quickly, the hospital had to pay a 5 percent premium. Additional cost was required to wire in the new generator and to have the rented unit unwired.
Even more troubling, because deadlines were especially tight, the hospital ordered the same size generator without considering the long-term needs of the facility.
Unfortunately, that’s a familiar story. Once the commissioning process and warranty years have come and gone, aggressive building-system maintenance becomes less and less of a priority.
Before long, inconsistent maintenance means building systems only get noticed when an emergency arises. Emergencies cost money — money that doesn’t add value to a business’ bottom line. Facility executives might be able to get by with a reactive approach to maintenance and upgrades. But taking a high-level management philosophy instead is a better approach, one that drives a return on investment for the physical plant.
Proactive management leads to the best financial outcome. Planned upgrades or replacements avoid direct costs, including temporary wiring, rental fees, unwiring, delivery, crane rental and repair of the location where the rental unit had been temporarily set.
The cost of lost opportunity, although difficult to quantify, can be more substantial than direct expenses.
One opportunity that is often lost is the chance to address the long-term goals of the facility master plan, while simultaneously accomplishing the maintenance needs of the current infrastructure. A proactive plan enables an organization to reap important benefits while spending no more than it would have spent by reacting to problems; the difference is that the money spent on the latter leaves the facility with no added value.
As a facility grows, it’s not unusual for projects to be based on the least immediate cost. Doing so is shortsighted. Replacing an existing generator or UPS system, for example, is a chance to upgrade to current technology, while implementing the facility master plan.
The key to success is an intelligent strategy. The strategy should be documented carefully because relying on the memories and skills of key people, no matter how well-intentioned, will lead to complications.
Finding the Best Approach
The first step is to undertake a comprehensive study of existing systems in light of the master plan. Often, facility executives can uncover synergies between proactive maintenance that avoids downtime and future needs as laid out in a five- or ten-year facility plan.
The following rules of thumb will prove useful in evaluating the existing infrastructure:
- UPS batteries should be replaced after six to seven years of service
- Generator engine life expectancy is 20 to 25 years
- Transfer switches life expectancy is 20 to 25 years
UPS Batteries: The UPS battery may have been specified as a 10-year unit, but experience shows that waiting that long may cause problems. In addition, filter capacitors used by the UPS will eventually fail. The lifespan on filter capacitors depends greatly on the design and quality of the components.
Consult with the manufacturer of the UPS to determine when these components should be replaced. In many cases, it may be better to replace the whole unit and upgrade to the most current technology. For example, UPS systems with active IGBT input stages can handle voltage swings in the power supplied by generators much better than older UPS systems; the resulting performance increase alone could be cause to replace the UPS.
Generators: Generators have a long service life. But it’s really total runtime, not the total years of service, that counts. If there has been a period during which the generator ran for days on end, expect to replace the generator sooner than normal, perhaps in 18 to 20 years.
Other things to watch include the generator’s alternators, which can fail. Alternator brushes also need to be maintained. Permanent magnet alternators require less maintenance because there are no brushes to replace.
While a skilled mechanic may be able to keep old generators running for as long as parts are available, it may not be the wisest option. Advances made with electronic isochronous governors, as well as NFPA 110 alarm and monitoring requirements, may make replacement attractive. Consider this: Spending a lot of money on an engine or alternator rebuild simply won’t buy another 20 years of service life.
Transfer Switches: Best practices call for the replacement of transfer switches before they experience full failure. Transfer switches should be closely monitored during monthly generator testing. At the first sign of a failure to transfer or any uncharacteristic noises, schedule a replacement.
Isolation by-pass transfer switches will allow the switch to be replaced without interrupting power to the load. Most large 24-hour facilities can justify the cost increase for these switches. Scheduling replacements during weekend downtime is a cost-effective option for smaller facilities.
The Right Documentation
A business case should be supported with detailed documentation. To complete a gap analysis — a review of what the facility actually has compared to the organization’s master plan — consider the audience. Documentation should be laid out in a manner that can be understood by all stakeholders.
As-built drawings are a good place to start. As-built drawings should give a complete plan of the facility, but information is often missing when a set of drawings for one project picks up from a previous project.
Furthermore, as-built drawings depend on the quality of the information red-lined on the drawings during construction. This is where things can be missed, in part because field construction conditions make it harder to keep accurate records.
A comprehensive survey can fill in the blanks. Whether it is better to perform facility surveys in-house or to hire a consultant depends on the size and experience of the in-house staff and the demands facing them. Either way, items needing review and documentation include generators, transfer switches, UPS batteries, UPS “inverter” for filter capacitor evaluation and TVSS units.
For the oldest items, determine if parts are still available. If so, remember that some parts may be selling at a premium because they are in limited production. Also, evaluate how long it takes to get the parts.
It’s also important to note any maintenance practices that are masking larger problems. Often the fix is clear but not clearly documented:
- Adding oil before each scheduled generator test.
- Ignoring the low-battery UPS alarm during testing.
- Running the generator for an hour before the inspector comes — a warm generator starts easier.
- Placing temporary fans in the generator enclosure for testing during the summer months.
- Overriding the UPS warnings on short overload situations.
Investing in Long-term Success
Documenting details can be tedious but revealing. For instance, it can be startling to find out how much cost is involved to rent a generator big enough to backup a typical hospital.
Rather than expending resources and gaining no residual value, it is crucial to consider the positive long-term impact of replacement. A detailed and accurate account will help justify the installation of a new N+1 generator, for instance, or an upgraded UPS system.
In some cases, it may be wise to team with an outside source. Engaging a consultant to work with the facility can expedite and strengthen a comprehensive facility maintenance plan. And keep in mind that it’s also important to involve the board of directors and other stakeholders to ensure a broad view and ultimate consensus.
With a meticulous maintenance plan and thorough documentation of the existing facility in place, a gap analysis will enable all stakeholders to determine priorities. It will also guide wise investments for the long-term stability and success of a facility, and ultimately, the organization that calls it home.
To Strengthen the Business Case, Examine the Impacts of Failure
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Mike Daugird, P.E., is an electrical engineer for Marshall Erdman & Associates, an integrated design-build firm that specializes in health care facilities. Daugird has more than 11 years of engineering experience and has collaborated on more than 75 health care facilities.