Loss of Electrical Power Procedure – Building Engineer Training

loss of electrical power procedureThis procedure is going to cover a loss of electrical power in your building.

There are a few situations that can occur at your facility that are more critical and emergent than others. A loss of electrical power is one of them. I would say it is in the top three of most critical. Depending on your facility or property, it may be #1.

I worked at a property where a certain bank leased out most of the floors. Two of the floors were deemed critical facilities. From what we knew as lowly building engineers, pretty much all west coast electronic transactions went through these two floors.

It was rumored that if these floors lost electrical power, “went down,” the bank lost close to $1,000,000 per minute in transaction fees. They put immense pressure on us to ensure that our emergency power generation system was always ready to roll and in perfect condition.



loss of electrical power procedures

Common power distribution set-up. From: www.econ.iastate.edu.

Actually it was more our company than the bank, we owned it all and they had very high maintenance standards and expectations – everything done in house, no contractors. It was awesome. The 5th Avenue building was aced out.

One way we ensured that we could handle a potential loss of electrical power was by having a procedure.

Our prodecure was of course written for that building specifically – which is why the one I’ve written below should be used as an outline, to give you some ideas. Jot down or print out the main ideas and adjust them to fit your needs. Stuff like this is golden for a rookie building engineer at his first building.

Your property will have different generators, controls, ATS’s, and loads among many other things – like systems AND critical systems.

While the procedure is the most important thing here, first let’s talk about some indications, things you may see ahead of time basically telling you in a second, a few seconds, or later, you are going to lose electrical power.

Loss of Electrical Power Procedure – Indications

Do I need to say it? This is not all inclusive.

Being Frank here, (capitalized on purpose, Frank is a straightshooter,) you might have like 3 milliseconds of indications before you have completely lost electrical power.

You might be sitting there, see a light flicker and then boom! Darkness. This is usually how it goes. “Did the lights just fl…?” Boom.

There are rare times though when they might flicker more than once.

  • Televisions may also flicker or the picture sags, shrinks, or like droops for a second over and over.
  • You may hear small UPS’s (uninterruptible power supplies) alarming, telling you that they have switched over to their internal battery.
  • Maybe you’ll hear the chillers or boilers cycling down.
  • Signal from your fire alarm control panel (FACP) telling you it too is on battery power.
  • Computers may go down.

I’m sure there are others. Can you think of more I should add? Let me know.


Loss of Electrical Power Procedure

1) Go to your generator control panel

emergency powerThis used to be where you would watch your diesel engines running. Now it is usually a computerized station that displays the status of your engines, ATS’s (automatic transfer switches,) and sometimes your entire electrical distribution system.

Go here to check the status of everything.

  • Are your generators running?
  • All of them?
  • Are the generator breakers themselves closed?
  • If not, then they are NOT supplying power to your building.
  • If they are closed, then your generator set got the signal from somewhere that they were needed up and running to supply electrical power somewhere.

2) Check your ATS’s

Automatic transfer switches. These electrical devices could have a whole post about them. Basically they monitor and control from where a device, like a pump, an outlet, or a light gets its power.

Usually ATS’s are in the normal position, meaning they are using utility or city power to drive all loads.

When we lose power, the ATS’s sense it instantaneously and switch over. They are like demanding electricity. This tells the diesels to start. Now. The diesel breakers close and give the ATS’s power on their emergency side.

If none have switched over, that means that either:

  1. you don’t have a loss of power or
  2. an ATS that thought it felt a loss of power and tried to switch but got stuck.

If all have switched over, then buck up comboy, you are out of power.

If one or a couple have switched, this usually indicates that somewhere down those lines ONLY, is there an electrical issue.

The ATS’s prefer to be on city power over diesel power. If they have the two choices available they will switch over to the city once it has determined it is reliable.

For example, we have a machine at my work that is on emergency power. Meaning it is always supposed to be able to operate. Sometimes it overloads and trips its own breaker. This switches just that ATS, this starts the diesels.

3) Check Equipment Status

Boiler re-fire?

Boiler re-fire?

Whatever your most important pieces of other equipment there are, start there. For most it would be the chillers and boilers.

  • Did they restart on their own?
  • Do you need to reset anything first?
  • Any alarms you need to clear in the digital control system in order to get them to run?

Start with your major equipment and go down from there. You won’t need to check certain, minor things right now.

There is going to be a balancing act now that you’re going to have to perform.

It’s monitoring the loss of power vs. taking action to restore power vs. making sure the facility is currently being taken care of.

Yes it can be stressful but it’s also kind of fun.  Get everything major that you can running again as you are checking the diesel control panel. Check your air handlers, fire system, control or compressed air system. Back to the diesels.

Ignore the outdoor irrigation system time clock for now. Ya dig?

4) Take Notes & Inform

Pretty easy point to make. As you have time, take note of what and when things happened, it can be rough.

Sure makes it handy for reference later and if you ever have to provide a timeline in a meeting or email.

As you have time, start calling. Call your supervisor or whoever is next up the chain if that’s what your job mandates.

Maybe not. Maybe it happens frequently enough that there’s a known difference between power outages and glitches let’s say.

5) Troubleshoot

Once everything is stable, try to figure out what went wrong.

By stable, this could mean still on emergency power and in between equipment rounds. That might be what your situation dictates.

Your number one priority at your place may be to restore the chillers at all costs. Do that first, and then try to figure out why the diesels started.

Back to the ATS’s.

  • Did they all shift?
  • Or just a few?
  • Is one stuck?

Now is when you would physically go to each ATS location and inspect it.

  • What position is it actually in?
  • Normal or emergency?
  • Does it need to be?
  • Is it getting a signal that it thinks it need to provide emergency power?
  • From where then?
  • Is one stuck?
  • Willyou have to manually shift it?

If nothing seems wrong, you may want to start checking each individual load off of the circuits.

6) Restore Power when You Can


Yep. Usually the ATS’s take care of this for us now. They sense when city power is back and watch it for a while.

They don’t switch yet, they just watch and make sure city is all cool now and isn’t going to freak out again. Then it switches over.

After that, the generator breakers should open which starts an engine cooldown timer. They will sit there at idle speed for a few minutes.

If you had a stuck ATS and you manually switched it to its normal position, you have probably just restored power. The ATS will get the signal everything is good and tell the diesels to go into cooldown.

After you restore, watch everything. Go back through and do the same equipment rounds you did before, following the same order.

If you are a building engineer long enough, you’ll get a routine. Check your major equipment, might be computer rooms, get it back online or make sure it never went down.

Once everything has been copacetic for a while, then you can start going through the less significant systems.

Whew. Not so bad really though right. Everything kind of flows down a simple path. You may have to make adjustments and modifications to this loss of electrical power procedure to suit the needs of your building.

If you’re not in charge, use the hopefully already established procedure. If you’re still not in charge and your facility doesn’t have one, somehow kindly hint around that you should. You take lead on it. Come up with it on your own, tailored exactly to the property.

Always be open to changes. Maybe you missed something and think of it three months later. Oh well, modify it. You thought of it now. Oh yeah, the fire pump needs emergency electrical power too! You see? Get to it people.

If you are looking to read even more, here is the emergency response procedure for the laboratory personnel at Bucknell University.  Notice how they write “in order not to overwhelm the physical plant personnel (us)…”  And here is a very detailed procedure from Brock University that they have very smartly written for their facility.

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