Testing Electrical Capacity of New Offices?

An anonymous reader asks: "Running a small graphic design studio, we've hit a snag that I'm sure many tech-reliant small businesses have hit before: our small flock of file servers, multi-processor machines and 22" monitors draws more electricity then the wiring in our current space can take. We're looking for a new space for this and other reasons, and as we look around we're generally forced to take the word of landlords as to what sort of amperage an electrical system can provide. Does anyone in the Slashdot community know a reliable way to test and see if an electrical system can support the needs of a computer-reliant business?"

Comments

Check the breaker box

[jspey]

Ask to see the breaker box that holds the breakers to your office space. The amperage that will trip each breaker should be printed on it. If it's not clear which breakers go to your office space (perhaps because there's one big box for the building and it's not labeled well, or there are different boxes for each office and they're not labelled well, either), ask the landlord.

Put in the lease that the electrical system in they office space will have a capacity of X. Have a clause that says that if this isn't the case, the landlord will spend his own money to fix it in X weeks/months/etc, and if he doesn't then you get free rent until he does, as well as the option to break your lease without penalty. Be willing to pay an electrician to check that the max amperage of the space is what it's agreed to before you sign the lease, though. Also make sure the lease allows you to have an electrician come in and do said checking.

If you're really worried, put a significant penalty into the lease if the amperage is too low (I'm sure you don't want to move any more than you have to). You will probably have to pay a little extra for this. If your landlord balks at this, tell him to get an electrician who will back his work do the inspection, so that the electrician pays the penalty and the landlord doesn't.

Re:Check the breaker box

[V. Mole]

The amperage that will trip each breaker should be printed on it.

And then divide that number by two. Or 1.5, maybe. Anyway, you can't pull 30A (or even 29A) through a 30A breaker, not for very long.

Re:Check the breaker box

[MarkedMan]

Whoa. While checking the box is the right way to go , simply adding up the current available on individual breakers is absoltely NOT! What you need to know is what kind of service the building has. If your space has its own service, then that is what you get, 200 Amps, 500 Amps, 1000 Amps. That is the total you can draw at once.

You still are not homefree though. State electrical codes limit how much each run can draw, say 20 amps. Even if you have a 10,000 Amp service, you can't draw more than 20 amps on that line. Note that the line can, and probably does, have mulitple outlets on it.

This is why you need a professional electrician. But you have to arm him with some prior information: In this room I want to have X pieces of equipment plugged in. Piece 1 draws 3 Amps, Piece 2 draws 1 amp, etc.

You can find out how much each piece draws with a clamp type ammeter, or rather your electrician can. Note that it is not unusual for equipment to draw significantly more at system startup.

The electrician can then calculate how many outlets and how many pieces you can plug in.

A suggestion: Color code and number the outlets for sensitive equipment and keelhaul anyone who plugs in a hair dryer or microwave. In fact, banish microwaves to some far off dungeon, as they emit noise at exactly WiFi frequencies (both use the unregulated spectrum, because, well, it is unregulated.)

Finally, I would also suggest putting all your sensitive stuff on an isolating power conditioner. This is NOT a battery backup, you can add one of those before or after it.

landlord scum

[Anonymous Coward]

most building unless they were build 50+ years ago should be fine. make sure your server room has a couple dedicated circuts so if you blow a fuse the whole thing wont go out. it all depends on what you have. 3 servers in a closet and 10+ machines in a 1000sq ft building with at least 6 dedicated circuts will be fine. if you are paranoid about it bring an electrician show him what you have and what type of building you are moving into.

Re:Have you considered?

[Chaostrophy]

Exactly, also, figure out what you need, cooling as well.

Look at JWZ's experiences at the DNA Lounge with electricity for some pointers and stories:
For one:
http://www.dnalounge.com/backstage/log/2000/ 07.htm l#20

here's a tiny url to a google search for all the related DNA stuff http://tinyurl.com/2msyt

Airflow

[Kobal]

You may also want to check how easy it will be to keep the rooms cool without adding too many electrical systems. If the airflow in the building isn't sufficient, you'll be drawing much more juice in summer.
Of course, depending on where you are, you may have the same issue in winter with isolation and portable heaters. If you use AMDs, this won't factor as an *extra* load, though.

Re:22" Monitors?

[Graelin]

The poster specified that they are a graphics design studio. Chances are they're using high-end CRTs for the color quality / contrast ratio.

Most LCDs are lacking in this area and those that are not cost significantly more than a similarly capable CRT.

Re:Check the breaker box = bad assumption

[managerialslime]

?????????????
>>Ask to see the breaker box that holds the breakers to your office space. The amperage that will trip each breaker should be printed on it.
?????????????

Really?

If the last electrician "installed" extra breakers in anticipation of future needs, (i.e. you've got switches without connecting wires,) looking at the box won't do you any good.

This is another reason why you should have a licensed electrician test the required electrical capacity prior to signing a lease.

The last two facilities I was involved with had to be upgraded. The first, because when we installed UPS' the heat from the UPS' overwhelmed the air conditioning.

The second because when an open space was suddenly converted to cube space, employees brought in a boatload of space heaters and pop-goes-the-breakers.

With regard to landlords putting guarantees in the lease, good luck. Many will tell you it's between you and the local utility and the most they will do is provide their "best efforts."

What you can OFTEN do is have your licensed electrician kill two birds by scheduling a representative from your local utility to meet with him when he inspects the site. At that time, any problems with the local power distribution grid THAT THE LANDLORD MAY NOT KNOW ABOUT can be identified.

With regard to estimating your needs, a google searches that include btu, kwh, "load estimation", etc. provides lots of links to help you develop a spreadsheet of what you need.

Need to talk to your realtor.

[R2.0]

If you are moving into a new space, you should have a construction allowance built into the lease. This will cover reconfiguring the office space and changing the electrical & mechanical systems. Why worry about mechanical systems? Because if you are going to need an electrical upgrade due to increased power consumption, you will need upgraded HVAC.

Before the lease is signed, get a design done and get bids on the work. The bids will give an honest account of the suitability of the space. You can now back out or go forward. If you go forward, negotiate the lease terms and the maximum cost of construction.

The work gets the work done by contractors, bills get paid by the landlord, you pay for it in your lease and it comes under operating expenses instead of capital expenditures - your accountant will love you (after they curse you for the up front hassle)

Use a Multimeter

[max born]

You need a heavy duty multimeter. You can get one with a rating of about 20 amps AC for under $50. like this for example.

Hook the multimeter up with a variable resistor (also rated for 20 Amps) in series with the circuit you want to measure.

(+)-->resistor-->multimeter-->(-)

Open up the resistor (slowly) until the circuit breaker or the fuse goes. Note the amps that this happened at. That's your max.

Re:Use a Multimeter

[Euler]

You can't be serious. Don't try this at home kiddies.

I've worked in my profession with high voltages and high wattage loads, actually. It's something that only engineers or fools should be tinkering with. If you don't know what I^2 * R is for, or how to insulate such a rig properly, then don't even think of it.

Re:Check the breaker box = bad assumption

[Anonymous Coward]

This is very good advice, but I would add a third party -- the HVAC people, and if you have chilled water that is maintained by another party, have them show up as well. That is a very good idea. And come to the meeting knowing how much the current draw is for each of your machines + 20%.

On another topic, the air filters that most HVAC companies and folks use are really, really crappy. It is worth the extra money to budget to get good air filters (we use 3M Filtrete air filters in our building and we no longer have any fine dust in the servers). Or, reserve down time to blow dust out of the systems a few times a year.

use ohms law

[splungent]

Use ohms law to figure out power consumption. e=i*r volts = amps * ohms or p=e*i Power(in watts) = volts * amps Oh..... Just go here: http://www.grc.nasa.gov/WWW/K-12/Sample_Projects/O hms_Law/ohmslaw.html or here: http://www.knovel.com/knovel2/Toc.jsp?BookID=687