This article will discuss standard electrical systems for today's office cubicles and partitions in laymans terms. Click the link for a dry yet informative article written by the fine folks at Haworth, which covers in depth terms and definitions Haworth Article. Please consult a licensed electrician in your city/state for local regulations and guidelines.
Sparky the electrician says- "Nice article, I'm sure. But I have been to electrical school and through my apprenticeship, I have twisted more wire, drunk more coffee, eaten more donuts and taken more breaks than you ever will, and I'm on the clock! How do I hook these things up!!??....." Calm down, Sparky and click here--> 8 Wire Diagrams
I seriously doubt he has eaten more donuts than me.
Todays electrical is usually an 8 wire system, older systems, pre 1990, are usually 5 wire. Our main discussion will be on the 8 wire systems. If you have questions about 5 wire electrical and single circuit electrical please call me 800-244-9499, email me.
There are two types of 8 wire electrical; 3 circuit and 4 circuit-
3 Circuit, 8 Wire Power
This type of electrical system has 3 hot wires (circuits), 3 neutral wires and 2 ground wires. Each circuit has its own neutral wire. There is also a common ground and an isolated ground. The Isolated ground is meant for sensitive equipment such as a PC, monitor, TV or other devices that may transmit disturbances from devices that have carraige returns or heavy moveable objects- Dot Matrix Printers, Type Writers, Popcorn Poppers, etc.
4 Circuit, 8 Wire Power
This electrical system has 4 hot wires (circuits), 2 neutral wires, and 2 grounds. 3 of the circuits share a neutral and a ground wire. The 4th circuit is usually a dedicated circuit and has its own neutral and ground wires.
How To Bring In the Building Power to a Cubicle System
Step one- Hire a licensed electrican familiar with your local regulations and ordinances.
There are two ways to bring power to your cubicle system, Basefeeds and Topfeeds. Your electrician will be able to determine which method is best for you.
Basefeeds- These are usually 1/2" diameter, seal tite conduit, which is 48"-72" in length. The basefeed plugs into the cubicle system and is hardwired to the building power. These can be hardwired to a floor monument or to a wall junction box.
Topfeeds- Topfeeds are "power poles" which attach to the cubicle system. The pole goes through the ceiling tile into the ceiling, where the electrician will run conduit from a buidling junction box and hardwire it to the junction box attached to the topfeed. Most topfeeds also have a shielded channel to run tele/data lines down into the cubicle system.
How To Determine How Many Circuits You Will Need For Your Office Cubicles
Popular concensus these days is for each cubicle to have 1/2 of a circuit dedicated to its use. Such as two cubicles will share one circuit, four cubicles will share two circuits and six cubicles will share three circuits. This is a good rule of thumb to go by but it is not always correct.
Let me bore you with some quick numbers here:
One Circuit has 20 AMPS. By NEC Code(National Electric Code, USA) we can only use 80% of the AMPs from each circuit, which is 16 AMPs.
NEC also states a maximum of (24) receptacles can only be used per circuit.
To determine the power usage (AMPs) for each cubicle a detailed survey must be accomplished. It is not that hard. Each piece of equipment that has a plug on it usually has a silver plate on the back that will tell you the power rating of that item. It should say something like- Power Rating: 100-240V-50/60Hz 1.5A .
The 1.5 A or whatever -A is the amount of AMPs that device uses. 1.5 A stands for 1.5 AMPs. Determine how many total AMPs will be needed for each piece of equipment and add them together. This will tell you the total Amperage usage you need. If it's less than 16 Amps you will need one circuit, 16-32 Amps you will need two circuits, over 32 Amps you will need 3 circuits, etc.
If you missed the Haworth Article, check it out. It has a lot of good info written by smarter people than me. Nice graphics also.
Please contact us with any questions.