Small rooms, big consequences
Plenty of Edmonton businesses run their whole operation from a closet: a couple of servers, a firewall, switches, a phone system and the camera recorder. When that closet loses power or overheats, everything stops.
A small server room does not need data-centre engineering, but it does need deliberate electrical planning. Most problems trace back to the same handful of shortcuts: shared circuits, power bars daisy-chained together, no UPS maintenance, and cooling that stops when the power does.
The good news is that fixing these is usually straightforward once someone looks at the room with fresh eyes.
Start with an inventory
- Every device in the room and its power draw, preferably measured.
- Which devices have dual power supplies.
- The plug types they use and the receptacles available.
- How long each must stay up during an outage, and whether a generator is available.
- Growth over the next few years: more storage, more PoE switches feeding cameras and access control.
That list drives the circuit count, UPS size and cooling load. A licensed electrician can turn it into a load calculation and a layout.
Measure the actual load where you can. Nameplate ratings on servers are usually far higher than what they draw in practice, and sizing everything to nameplate can lead to an oversized UPS and needlessly large circuits. A short logging period with a power meter, or the readings from intelligent PDUs, gives real numbers.
The power path
- Dedicated circuits. Server room loads should not share circuits with the office kettle or a printer. Give each PDU its own circuit.
- A and B feeds. Dual-corded servers are only redundant if their two cords go to different PDUs on different circuits, ideally from different sources.
- UPS with bypass. Lets the UPS be serviced without a shutdown. See UPS systems for businesses.
- Generator coverage. If you have a generator, cooling must be on it too, not just the IT load.
- Surge protection at the service and the distribution panel adds a layer beyond what the UPS does.
Plugging power bars into power bars, or a UPS into a power bar, overloads cords and receptacles and is a common cause of fires and trips. Use properly installed PDUs on dedicated circuits.
Inside the rack
Put heavy UPS units at the bottom. Keep power cords on one side and data cables on the other where you can. Label every PDU with the panel and circuit number that feeds it, so anyone can find it quickly at 2 a.m.
Cooling is part of the power plan
Every watt your equipment uses becomes heat. A closed closet with a few servers can climb past safe temperatures quickly once the air conditioning stops.
- Size cooling to the IT load plus UPS losses and lighting.
- Put the cooling unit on the generator if there is one, and confirm it restarts by itself after a transfer.
- Add temperature monitoring that sends alerts.
- Do not count on the building's general HVAC, which may set back at night or on weekends.
Edmonton winters do not help as much as you would think. The room still needs mechanical cooling, because outside air is not getting in without a designed system.
Cooling equipment also needs its own dedicated circuit, and its controls should be set to restart automatically after power returns. A unit that needs someone to press a button after every outage will eventually be forgotten on a long weekend.
Keep the room clean and the door closed. Dust and open doors both make the cooling work harder.
Grounding, labelling and documentation
- A proper telecommunications bonding busbar, with racks and cable trays bonded to it, as designed by your electrician and cabling contractor.
- Panel schedules updated to show which circuits feed the room.
- Labels on every receptacle and PDU.
- A simple one-line diagram taped inside the room door.
Data cabling should follow the same discipline. Read structured cabling basics for the low-voltage side.
If you are fitting out a new space, involve your electrician and IT provider at the same time. Moving a server room after the walls are closed is slow and disruptive.
Testing and keeping it healthy
A server room power plan is only as good as its last test. Once a year, ideally during a planned window, walk through a simulated outage with your IT provider and electrician.
- Confirm the UPS carries the load and sends alerts.
- Confirm the generator starts, transfers and picks up cooling as well as IT.
- Check that servers shut down cleanly if the test is extended.
- Pull one PDU feed and confirm dual-corded equipment keeps running.
- Review temperature logs and look for hot spots.
Record what worked and what did not, then fix it before an unplanned outage finds the same weakness.
Common questions
How many circuits does a small server room need?
It depends on the load, but at minimum each PDU should have its own dedicated circuit. A room with dual-corded servers typically has at least two, fed separately.
Can I use regular power bars in the rack?
Use rack PDUs rated for the load and plugged directly into dedicated receptacles. Consumer power bars are not designed for continuous heavy loads.
Does the air conditioner need to be on backup power?
If the equipment runs during an outage, yes. Without cooling, a small room can overheat long before the UPS or generator runs out.
Who should design this?
A licensed electrician working with your IT provider. For larger rooms or new builds, an electrical designer may prepare drawings for the permit.
Codes and permit rules change and every building is different. For work on your system, talk to a licensed electrician and your local permit authority.