New Electric Circuits Testing Regulations

Useful Revit Tricks Every Electrical Engineer Should Know

This is a guest post by electrical engineer and Revit expert Dillon Mitchell. As you’ll see, Dillon has a lot of experience with Revit and has learned a bunch of tricks that help him work smarter and faster. In this post, he shares five of his best tips

When I first started using Revit, I found the software to be overwhelming. First, there are all those buttons and options. Second, everything was wide open. It seemed that with Revit, if you can imagine it, you can create it. It’s a powerful tool but it can also be intimidating.

Getting started took some effort and I tried to learn just one piece of the software at a time. In a way, I found Revit to be a lot like Excel – there are deeper and deeper levels to it. Yet I made progress learning the software by starting on the surface and mastering the basics.

Set Your Load Classifications

Load classification in Revit segments your loads into different classifications. These classifications will be put on your panel schedules and are useful when filling out utility letters at the end of a project. The utility company uses this information to size the transformer at the service entrance. Typically, this information takes a long time to collect; you need to add up all the receptacle loads, lighting loads, largest motor, as well as heating and cooling loads. When done throughout the course of the project, this information is simple to provide.

Understand Type vs. Instance Properties

Revit has two kinds of parameters; type parameters and instance parameters. Understanding when and where to use each kind of parameter is critical for an efficient workflow.

House Wiring for Beginners

In a typical new town house wiring system, we have:

Live & Neutral tails from the electricity meter to the CU

A split load CU

Ring circuits from 32A MCBs in the CU supplying mains sockets. 2 such rings is typical for a 2 up 2 down, larger houses have more.

Radial lighting circuits from 6A CU MCBs. 2 or more circuits typical.

Earth connection from incomer to CU.

10mm² Main equipotential bond to other incoming metal services (gas, water, oil)


Earthing is a fundamental safety system used in electrical installations. It works in co-ordination with circuit breakers MCBs, Fuses, and RCDs to ensure that an electrical supply can be disconnected quickly in the event of a fault. This greatly reduces shock risk.

Residual Current Devices (RCD)

The 17th Edition of the wiring regulations impose more frequent requirements to install RCD (or RCBO) protection than the previous 16th Edition. In general, ANY cable which is buried less than 50mm below a wall’s surface AND is NOT mechanically protected, or wired in one of a number of specialised cable types that incorporate an earthed screen must have 30mA trip RCD protection. Such circuit protection may be derived from either an RCD protecting several circuits, or individual RCD/RCBOs on each circuit.


An RCBO is a combined RCD and MCB in one module, and is fitted in place of an MCB. RCBOs allow individual circuits to be protected by their own RCD without any risk that a fault in an unrelated circuit could cause it to trip. However protecting all circuits like this is more expensive.

Neutral Connections & RCDs

Neutrals for circuits protected by different RCDs (or those from an RCD and non RCD protected circuit) must not be mixed. If any neutral wire is connected to the wrong side, the RCD will trip. The same principle is true for RCBOs, each RCBOed circuit needs to have its neutral connected to the RCBO neutral and not elsewhere.

tips to prevent electrical fires at home

Electrical fires can do some serious damage to your home and put your family’s safety at risk. The good news is electrical fires are often preventable

Keep heat-producing appliances unplugged when not in use. When heat-generating appliances malfunction or are accidentally left on for an extended period of time, they can overheat and catch on fire. It’s safest to unplug kettles, curling wands, toasters, irons, and other “hot” appliances when you’re not using them.

Only use extension cords temporarily. Extension cords should be used as temporary solutions only. If you need additional permanent power sources installed in your home, contact a qualified electrician

Never cut off the third prong on a power cord. The third prong (also known as the “ground”) is there for a reason: to protect you in the event of a power surge or other electrical malfunction. If your home only has two-prong outlets, consider having an electrician inspect your home’s electrical system to see if they can update your outlets to three-prong ones.

Update your home’s electrical system. Knob-and-tube wiring, aluminum wiring, and 60-amp electrical systems (commonly found in older homes) tend to come with a greater risk of overheating. Consider upgrading to an electrical system that uses modern wiring materials (like copper, for example) and has at least 100 amps to reduce your chances of an electrical fire

Tips to Draw Your Next Schematic Design Like a Pro

Ready for that next great idea for a PCB project? It’s all starts with your schematic design. Unlike a PCB layout, which is all about the physical placement of parts and copper, a schematic is more theoretical, describing how components are electrically connected. And while you won’t necessarily know how parts physically connect when drawing a schematic, you will know exactly how a signal will move through your circuit. Sounds easy enough, right? Not so fast.

Clearly Show How Your Wires Connect

You’ll be relying on wires to define connections between symbols on your schematic drawing. In Autodesk EAGLE you’ll see these referred to as nets. Regardless of what you call them, there are several guidelines to keep in mind.

Complete Net Connections When It Makes Sense

The entire goal with a schematic is to make your circuitry as easy as possible to understand when you read it in the future or hand it off to another engineer. To aid with this process of readability, it’s necessary to minimize any unnecessary net connections when they aren’t needed.

Always Use the Same Symbol for the Same Device

If this is your first schematic drawing, then you might be surprised to know that there are several different ways you can draw schematic symbols. This all depends on what side of the world you’re living in, and what standard you plan to follow

Make Sure Every Part Has a Unique Designator

This is another tip to enhance the consistency and readability of your schematic. Every symbol on your circuit needs to have its own unique designator so that every part is easily identifiable. For example, every resistor should follow a consistent naming sequence of R1, R2, R3, etc.

Earthing And Bonding

Why do earthing and bonding need to be checked?

If you are having an alteration of addition made to your electrical installation, your electrician must check (as well as other things) that the earthing and bonding arrangements you have are up to the required standard.

What is earthing?

If there is a fault in your electrical installation you could get an electric shock if you touch a live metal part. This is because the electricity may use your body as a path from the live part to the earth part.

Earthing is used to protect you from an electric shock. It does this by providing a path (a protective conductor) for a fault current to flow to earth. It also causes the protective device (either a circuit-breaker or fuse) to switch off the electric current to the circuit that has the fault.

What is bonding?

Bonding is used to reduce the risk of electric shocks to anyone who may touch two separate metal parts when there is a fault somewhere in the supply of electrical installation. By connecting bonding conductors between particular parts, it reduces the voltage there might have been.

More advice

An electrician will give you advice if your earthing or bonding needs to be improved for safety reasons. We strongly recommend that you use an electrician registered with a government approved scheme to carry out any electrical installation work you need doing.