WHAT IS A TERMINAL BLOCK?

What Is A Terminal Block?

A terminal block (also called a connection terminal or terminal connector) is a modular block with an insulated frame that secures two or more wires together. It consists of a clamping component and a conducting strip. A typical simplest terminal block is as shown in the image below.

The insulating body of a terminal block houses a current carrying element (a metal strip or terminal bar). It also provides a base for clamping element. The body has a mounting arrangement so that the block can be easily mounted on or unmounted from a PCB or a mounting rail. Most terminal blocks are usually modular and mounted on DIN rail. That allows us to increase the number of terminals according to the requirements. Terminal blocks keep connections much more secure and wire’s well organized.

 

Types Of Terminal Blocks

Electrical terminal blocks can be classified on the basis of structure, device type, termination options etc.

 

Structure Type

Single level pass-through terminal blocks: These are simply used to connect two wires together, i.e. wire-to-wire connection. These are also called as single feed terminal blocks. Single level terminal blocks are of the most simple type having one input contact and one output contact.

Dual level terminal blocks: These blocks have another level of connection terminal stacked on the first one. This arrangement is generally used to save space.

Three level terminal blocks: Just like dual level blocks, these have an extra level at the top. An advantage of using multilevel blocks is that multiple connections can be made in the same block.

Device Type

Ground Terminal Blocks

These blocks often look like a single level feed through terminals. The exception is that these blocks and the metal connection where the wire is terminated are grounded to the panel or DIN rail on which the block is mounted.

Fused Connection Terminals

These are similar to the pass-through blocks with an exception of the metal connection strip is replaced with a fuse. Therefore, the wires will be connected through a fuse providing an added protection.

Thermocouple Terminal Blocks

These are designed to accept thermocouple lead connections. Some thermocouple connectors essentially clamp the thermocouple leads together on both sides of the block, eliminating the metal connection strip inside the block. However, in some thermocouple blocks, the metal connection strip of the same metal as that of the wire may be present.

I/O Blocks And Sensor Blocks

I/O blocks are used to make a connection between a device and a controller. Whereas, sensor blocks handle three or four wire devices such as proximity sensors.

Disconnect Terminal Blocks

These blocks allow wires to be easily disconnected just by lifting a lever or knife switch. They can be used for convenient disconnection and connection without removing the wires. They are also known as switch blocks.

Power Distribution Blocks

These blocks are used in electrical power distribution. An electric power distribution terminal block is a convenient, economical and safer way to distribute power from a single input source to multiple outputs. One large wire is connected to the input terminal of the block and multiple output terminals are provided at the output. This way, wires are well arranged in a control panel giving it a neat, clean and professional look.

Clamping Options In Terminal Blocks

Screw terminal: Screw clamp terminals are the most common type of connection method. The wire or conductor is simply pressed against the conductor strip in the block by tightening the screw. Screw terminals accommodate a very wide range of wire or conductor sizes.

Spring clamp: These type of terminals use spring pressure to retain the wire clamped. Spring clamps are a newer alternative to screw clamps and are generally used for relatively small wires.

Push-in terminal blocks: Push-in terminals allow you to connect a wire simply by inserting it. Most push-in terminals require the use of a ferrule. A ferrule strengthens the end of the wire/conductor. However, some push-in terminal blocks allow to insert a solid conductor directly or a stranded conductor by inserting a screwdriver into the release hole.

Insulation Displacement Connector (IDC): These connectors do not require us to strip the insulation for contact. We simply need to insert the wire without stripping the insulation, and the two sharp metal blades inside the terminal will cut through it to the conductor making proper contact.

Barrier terminal block: These are used where vibration is an issue. A spade or ring terminal is attached to the wire and then inserted into a bolt and tightened with a nut on the terminal block. This prevents loosening of the wire due to vibrations.

HOW MALFUNCTIONING APPLIANCES CAN CAUSE ELECTRICAL DAMAGE

When one of your appliances starts showing signs of disrepair, you might think the trouble is confined to that appliance only. But that’s not necessarily true — there are some ways in which a faulty appliance can send surges of electricity into your home’s electrical system, and the resulting damage can range from a tiny bit of wear and tear on other appliances to a destructive electrical fire.

With these consequences in mind, it’s important to discontinue use of an appliance if you suspect there’s a real problem. Seek out a repair professional who can fix the underlying issue and give you the all-clear to plug it in again.

 

What’s the Worst That Can Happen?

When a fizzling appliance sends a significant burst of electricity into your electrical system, your circuit breaker should trip. If you weren’t expecting this, a tripped circuit breaker may be your earliest sign that something is wrong.

It’s also an important safety mechanism designed to prevent further electrical damage, so you shouldn’t just flip the breaker back on while ignoring the root cause. Doing so will only create more opportunities for electrical damage.

Even with the protection of your circuit breakers, malfunctioning appliances can potentially cause you problems in three ways: surge damage, physical damage and fire damage.

Surge Damage

Chances are that you use a surge protector in conjunction with your home computer, and possibly with your television and other home theatre electronics. Perhaps you even have whole-home surge protection installed. This technology protects sensitive microprocessors that can be easily damaged by power surges, which can originate with lightning strikes or power outages.

But those surges can also take place internally, and this happens every day — appliances like air conditioners and refrigerators typically use an excess of energy when they initially switch on, sending small surges of power to other appliances on shared circuits. Faulty appliances can sometimes send much larger surges.

 

When this happens, microprocessor-based electronics can receive permanent damage in an instant. They may also experience cumulative damage over time from smaller surges, which can reduce device lifespan.

 

Physical Damage

Large surges can literally burn some electrical components, such as the delicate connectors in light switches and electrical outlets. When these components are replaced after this type of damage, you can often see the telltale scorch marks and melted plastic.

It takes only a fraction of a second for a flash like this to render a switch or outlet inoperable, and damage can occur even if your circuit breaker trips. You should always consult a licensed electrician to help you replace damaged components and track down the source of the surge.

 

Fire Damage

In the worst-case scenario, a malfunctioning appliance will cause an electrical short that sparks a fire. These may be tiny fires that flare out on their own inside metal appliances, but depending on where they occur, they can ignite insulation, wallpaper, curtains or other materials that may allow them to spread quickly. This is why it’s so important to address appliance failures at the earliest signs of malfunction.

Besides proactive repairs, your best defence against this disaster is a combination of working smoke detectors, accessible fire extinguishers and fire safety education.

WHERE DOES YOUR ELECTRICITY COME FROM?

From flipping the light switch and turning on your phone to reheating a snack in the microwave, the everyday activities we take for granted utilise an essential energy source – electricity. Now that you stop and think about it, you might wonder how this power arrives at your home from once it’s been generated. As we’ll outline here, the electricity we take for granted makes a long journey from the power station to your home. So, here’s how it gets delivered to you…

 

Australia’s electricity grid

Australia’s electricity grid spans more than 4,500 kilometres, and that’s just the eastern and southern states. Western Australia, the Northern Territory, and Mount Isa in Queensland have individual transmission and distribution networks. With more than 40,000 km of transmission lines, the main electricity grid includes transmission and distribution elements that allow transportation across the vast distances to your home. Australia’s grid is relatively efficient, with an average of 5% of electricity lost through the transmission and distribution process. This is a relatively low figure compared to loss rates for other countries.

 

Power stations

Electricity starts its life in a power station. Power stations are huge plants – often located near energy sources like natural gas plants, hydroelectricity dams, and solar or wind farms – that produce electricity. Depending on the type of fuel or source of energy input – whether it’s coal, solar, wind, or even nuclear – power plants may have components such as a furnace, boiler, turbine, cooling towers, and generators. These types of components are essential for the generation process.

Once the electricity is generated, it leaves the power station through overhead lines to large substations. At this stage, the electricity can be at as high as 25,000 volts or even higher.

 

First substation transformer

Substations are usually located near power stations. Substations play an important role in the electricity transmission process: they further increase the voltage of the current, allowing it to be sent over long distances without losing too much power. Substations do this by using transformers, and these can be used to either increase or decrease the voltage of electric currents. Decreasing the voltage of electricity can be important at distribution substations as it needs to be made less powerful and safe before it enters your house.

Once it passes through the first substation transformer, your electricity makes its way to the transmission networks.

 

Transmission networks

The transmission networks help shift electricity from power stations on to distribution networks to facilitate delivery to households, businesses, and other end users. At this stage, the electricity remains at a high voltage since it still needs to move across vast distances.

The transmission networks are made up of overhead lines on metal pylons or lines buried under the ground. These lines are designed to carry ultra-high voltages and they’re insulated to prevent the electric current from accidentally moving to the ground, where it can be dangerous for people.

 

Second substation transformer

At the second substation transformer point, your electricity is reduced in voltage, again through the use of transformers, to make it safe for use by households and end users. At this point, the electricity is considered to have reached the distribution network and left the transmission network.

The type of substation and voltage can vary depending on the use and location. For example, in rural areas, smaller substations might be used to reduce the voltage to around 33,000 volts, which makes it suitable for powering trains and factories. In urban areas with factories, the voltage could range between 11,000 and 33,000 volts to serve smaller factories. Contrast with delivery to homes, offices, and business, where the neighbourhood transformer might lower the voltage to as little as 230 volts.

 

Distribution power lines

Once your electricity leaves the substation transformer, it enters distribution power lines on its way to the final destination. Power lines can be overhead or underground, and they’re a familiar sight in most areas around Australia. Once it reaches your neighbourhood, the electricity passes through a small pole-top transformer for another voltage reduction. This ensures it’s safe to use inside the home, office, or business.

 

Your home

Your electricity passes through the service drop and gets recorded at your metre. The metre tracks how much electricity you use. At your switchboard, your electricity gets divided up into circuits for each area of your house. Finally, the electricity moves through wires behind your walls to power outlets and switches, where you operate your lights and appliances.

It’s easy to take the electricity used to light your house for granted, but this precious energy source has travelled a long way, through the complex generation and transmission infrastructure, to get to your house. Knowing this, you’re probably less likely to take electricity for granted when you next switch on your light or power up the TV.

 

WINTER IS COMING! HOW TO PREPARE YOUR HOME FOR WINTER

Winter-is-Coming

As the season slowly shifts from fall to winter, taking the time to prepare your home for cooler months is highly recommended. Proactive home maintenance can thwart unwanted disruption from unexpected bills and weather-related problems.

Below are six areas of your home that should be considered when preparing your home for winter.

Fireplaces
For those ready to enjoy a true wood burning fireplace, having the chimney inspected before lighting it for the first time is always a good idea. Inspections can be done once a year and often signal the need for cleaning. Blockages accumulate in the form of soot and creosote. While soot can impact the performance of the fireplace, creosote is highly flammable and may lead to a chimney fire. Find a reputable chimney sweep to inspect and clean your fireplace.

Furnaces and portable heaters
Furnaces and heaters left unserviced are often those that quit working in the dead of winter. It is recommended to service a furnace annually. Preventing both health risks (like carbon monoxide leakages) and other malfunctions, furnace servicing would be irresponsible to ignore. A servicing might include ensuring the thermostats are working, looking for leaks, checking electrical connections, lubricating parts, and changing filters. Opting to service your furnace annually is an inexpensive endeavour when compared to the cost of the emergency services and living in the discomfort of the cold.

Drainage
Rather than checking gutters and downspouts once in preparation for fall/winter, it is helpful to check on them regularly. Gutters and downspouts are responsible for diverting thousands of gallons of water away from the exterior and foundation of your home. During fall/winter leaves and debris fall off surrounding trees clogging gutters and wreaking havoc on your drainage system. Uncleared gutters can lead to serious exterior damage to your home including water ingress. Rust and corrosion are also possible when gutters are left unchecked.

Windows and Doors
To save energy, heat, and money, walk around your home to inspect the caulking on windows and doors. Check areas where masonry meets siding around doors and windows. Caulking should be present and free of cracks. When cracking is detected consider adding fresh caulking. Aside from keeping you warm, well-sealed windows and doors also eliminate the likelihood of mould.

Seasonal home maintenance is similar to car maintenance. When ignored, the cost and disruption of putting off simple maintenance will balloon into unnecessary costly bills and frustrating life disruptions. Consider adding this checklist to your calendar and making this part of your annual winter prep routine.

One-off portable heater servicing!

At Camtec we have a great deal that runs all year round! Our one-off portable heater services mean that you only have to worry about one cost to check out your unit, with the no worry and no hassle of hidden charges. We will also be able to let you know if there are any faults with your unit and ensure it is working perfectly to keep you nice and toasty in the winter.

ELECTRICAL WIRING COLOUR CODES

If you want to do a bit of DIY in the home or see what may be wrong with your wires then you will definitely need to know what the different coloured wires generally mean. Although, we do highly recommend to leave these jobs to the professionals for safety reasons it is helpful to know the differences.

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Electronic Dummies

BASIC ELECTRICAL TERMS

If your a DIY person or just want to be a bit more up with the lingo when your local sparky drops by you might want to know some of the basic electrical terms and concepts that they may use. Below are some of the key terms that you may want or need to know next time you have an electrical issue.

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