Frequently asked questions (FAQs)

We have compiled a list of general questions we are commonly asked to assist in your use of this site.
FAQs relating to a specific material can normally be found on its own page.
If your question is not answered here please do not hesitate to contact us - and we will do our best to help!


Why does my florescent fixture make a humming sound?
The ballast in florescent fixtures often causes a humming sound while the fixture is on. There are a number of possible causes for this. One cause could possibly be loose laminations in the core. However, manufacturers claim that this is not common.

Another, more likely cause, can be magnetostriction. Magnetostriction is the deformation of a ferromagnetic material subjected to a magnetic field. In other words, when the magnetic field produced by the ballast slightly changes the positions of the molecules in the metal, this creates a constant cycle of shrinkage and expansion that produces an audible hum.

Another possible cause, (or at least may contribute to the cause) is the way the ballast is mounted onto the surface. A simple fix is to install vibration-isolation pads between the ballast and its mounting surface to dampen the noise

Can I put a timer on a water boiler so that it will go on even if I’m not home?
Of course you can. You usually have a choice of either replacing the existing water boiler switch with one that incorporates a timer, or installing a timer in the electrical panel to control the boiler line. A reliable electrician can tell you which would be best in your case.

Sometimes the main breaker jumps but none of the smaller ones do. Why does that happen?
A basic, standard electrical panel found in many homes includes, in addition to other parts, a main breaker, and other "line" breakers. The main breaker supplies electricity to the line breakers, and is rated at a higher current rating (usually 25 or 40 amps in a standard one phase system). The other breakers supply electricity to the various lines around your home (usually rated between 10–20 amps). Let’s assume that your main breaker is rated at 25 amps, and you have 5 other breakers rated at 10 amps each. Now let us suppose that you are using on each line (each 10 amp breaker) only 8 amps. Each 10 amp breaker, having only 8 amps going through it, would be fine. They would have no reason to trip. But if you add up what each breaker is using, you get 40 amps. This is way over the amount that your main breaker is rated for, and will therefore cause it to trip.

Both the main breaker and the main ground-fault interrupter turn off everything in the house. What is the difference between them?
True, in a standard panel, both the ground-fault and the main breaker shut off everything in the home. But they both jump for completely different reasons. A breaker basically cares how much current is going through it and it really doesn’t care what you do with it. So, for example, if you had an outlet on a 16 amp line (breaker). You can plug in a heater, toaster, hairdryer, and even stick your finger in the socket (G-d forbid), but as long as you don’t take more than what the breaker is rated for (16A in this case), it will continue to work. The Earth leakage circuit breaker E.L.C.B on the other hand, even though it’s physically built for a range of current, it really doesn’t care how much current is going though it.

Whether it’s 10A, 16A, 25A, or 1000A - as long as what is going in is making a complete circuit, and nothing is escaping, the ELCB is quite happy to continue working. BUT, once some current “leaks” from the line out to someplace else, the ELCB will jump immediately. This is why it is sometimes referred to as “The Safety Device”. If someone would, G-d forbid, stick their finger in an outlet, part of the electricity from the line would flow through their body and on to the ground that they are standing on. The ground-fault would sense this (that not all the electricity going into the line is through the proper circuit) and jump, possibly saving his/her life.

You can have a situation where both the ground-fault and the main breaker (or specific line breaker) jump together. That would happen when a live wire shorts with something other than the neutral wire (i.e.: if the live wire of a room heater shorts with its metal body).

To summarize, the breaker jumps when too much current is being used (including a short), and the ground-fault jumps when there is a leakage of current from the line.

Can I simply upgrade my breaker to one with a higher rating, so to keep it from jumping all the time?
Definitely not! Each breaker in your panel is there for the sole purpose of protecting the wires that run through that particular line. If, for example, the wires are a size that needs a 10A breaker to protect them, and you were to switch the breaker to a 20A, you would be causing a potentially dangerous situation. There would be nothing to protect the wires from burning up and taking the whole house with them.

Can I get electrocuted by batteries?
You sure can, but you would need a lot of batteries to accomplish this. Regular everyday batteries are safe because they have such low voltage. You need a high enough voltage in order to get the current flowing through your body. Human skin is not a good conductor. It takes about 40 volts, or more, of electrical pressure to penetrate your skin and create an electrical current inside your body dangerous enough to harm you. Most of the batteries we use are 12 volts or less. On the other hand, if the current finds a way to penetrate the skin (through a cut or other opening), then even a 12V battery could be dangerous.

What do the colors of the plastic insulation mean on wires?
They are designed to indicate their use. In Ireland, the wires carrying current at full voltage are usually brown. Neutral wires are usually blue. Ground or Earth wires are usually yellow with a green stripe. Much caution must be applied, because wires are not always hooked up correctly. There are also older houses wired with the “old” colors, which are red (live), black (neutral), green (earth).

I have never had a doorbell installed. Is there an easy and quick way to install one?
Yes. You can install a wireless doorbell. We do a nice Friedland Plug in or stand alone 50mts or 100 mts range.

How can I know how many amperes my appliance uses?
The easiest way is to simply look for where it is written on the appliance. Many appliances have it marked somewhere. If not, then you can divide the watts by the volts (example: 2000 watts / 220 volts = 9.09amps). This isn’t 100% accurate because you usually have other elements that come into play, such as efficiency and a power factor. But for a "ball park" calculation it’s probably good enough.

How can I stop static electricity?
An electric charge is produced when two pieces of material are rubbed together, such as when you walk across a carpet and get a shock when you touch an object. In this example, you are building up a charge by having your shoes rub on the carpet, and this charge is transferred to you and is discharged on the object. These charges are called static electricity. You get static electricity when one material (even insulators such as rubber or glass) transfers its electrons to another. Static electricity occurs quite often when the weather gets cold and the moisture in the air is low. Therefore, adding moisture to the air would be a big help. Grounding is the best way of removing static electricity, but is not always practical. Using humidifiers or placing water next to heating ducts can help. Moisture in the air will be absorbed by the carpet fibers. Some carpets are made out of antistatic materials.

Why do we use AC electricity instead of DC in our homes?
Power is the product of voltage x current (P = VI)... For any given amount of power, a low voltage requires a higher current, thus requiring a larger size conductor (P = I2R) to transfer it from one place to another. Therefore it is more economical to transfer power using high voltage, thus requiring a smaller diameter cable. It is very difficult to transform DC power to a high-voltage, low-current form efficiently; therefore it is not transmitted for distances greater than one mile without introducing excessive voltage drops. On the other hand, AC power can be changed with ease using transformers to change the voltages. This makes it much more practical to use for distributing purposes. Even in your home, AC transformers can be found in use with many appliances.

What is the difference between 3 phase and single-phase electricity?
I suppose the textbook definition would be something like this:
A phase is the factional part of the period of a sinusoidal wave, usually expressed in electrical degrees.

A single-phase circuit is an alternating-current using only one, sine wave type, current flow.

A three-phase circuit consists of three different sine wave current flows, different in phase by 120 degrees from each other. Now let's have the more practical, "down to earth" definition - something that the average homeowner would at least have a chance of understanding:

Single phase: a circuit that consists of three wires – live, neutral, and ground (earth). The main breaker in a single phase system is a single pole breaker, resembling the others in the panel, only with a higher capacity.

Three phase: a circuit where the main breaker switches off three poles. For most home owners this is the equivalent of having 3 separate main breakers that are divided among the circuits of the home. There are 5 wires that normally constitute a three phase line, although in many homes the three phases simply supply the main and sub panels, but continue throughout most of the home as single phase lines. In most homes there are not many devices that run on three phase electricity. However, examples may include a three phase central air conditioner, a three phase oven, a 3 phase swimming pool pump, or a large 3 phase hot water boiler.

Do I need a surge protector for my computer?
Most places in Ireland still have relatively frequent power surges. Most people are well acquainted with the normal surges that cause permanent damage to appliances in a blink of an eye. But few people are aware of the smaller surges that are going on all the time. Unlike the larger surges that wreck havoc all at once, these smaller surges can slowly wear out the wiring insulation and electronic circuitry in your appliances, causing them to operate improperly and wear out prematurely. A good quality surge protector can do a lot to protect your computer as well as other appliances. I personally recommend buying a UPS for your computer. They may be slightly more expensive, but afford your computer much more protection.

What is the difference between a surge protector and a UPS?
A surge protector is a device that simply protects your computer (or any other appliance) from electrical surges, spikes, and other fluctuations in the voltage. Surge protectors vary greatly in both price and quality. It's usually wise to stay away from the "cheap" models. They will give you very limited protection, if any. A UPS (Uninterrupted Power Supply) usually has surge protection built in, but that's not all. It has a battery backup that offers you at least a few minutes time (if not longer), to save your work and turn off your computer (or other device) properly. Most have a communication cable between the computer and the UPS, to signal the computer when the UPS battery is low. This tells the computer to start shutting down automatically without you having to be there. Another plus in having a UPS is that it eliminates the frequent, short blackouts or brownouts (common to many areas around Ireland) which cause havoc with your hard drive. This can cause the drive to malfunction prematurely and have permanent damage.

I have many appliances with two prong plugs and my outlets are made to accept three prong plugs. Is using 2 prong plugs in the 3 prong outlets dangerous?
Most appliances that are bought in the store with a two prong plug are either made of plastic and do not need a ground wire, or are double insulated, in which case it would actually be dangerous to have it grounded. If the plug was installed by someone other than the factory or a reliable electrician, then it should be inspected by someone trustworthy.

Can I put a timer on a water boiler so that it will go on even if I’m not home?
Of course you can. In Ireland you usually have a choice of either replacing the existing water boiler switch with one that incorporates a timer, or installing a timer in the electrical panel to control the boiler line. You can even now operate your heating by your mobile phone. A reliable electrician can tell you which would be best in your case.

What is the difference between a transformer, a converter and a power supply?
A Transformer is an electrical device by which alternating current of one voltage is changed to another voltage using coils. There are several different types, but they all basically do the same thing - change the voltage. They are usually heavy for their size due to the weight of the coils (size and weight depends on their rating).

A Converter is an electronic device that is used in some cases instead of a transformer. The converter doesn’t actually lower the voltage, but rather delays each electrical cycle making the device think it is working with the proper voltage (does not produce an output of full sine wave electricity). If you were to measure with a voltmeter the output of the converter, it would actually measure 220V (in Ireland). These converters are not to be used with any electronic devices, and I personally do not recommend using them with ANY device. Although they are sold for use with hair dryers, bottle warmers, irons, etc, I’ve seen too many of these appliances ruined when used with a converter.

In actual fact, anything that supplies power is a Power Supply. But usually when people talk about power supplies, they are talking about a device that not only lowers the voltage, but also converts AC (alternating current) to DC (direct current). These are what you find on many small electronic devices (walkman, cordless telephones, desk clocks…etc), looking like a small black box that gets plugged in the receptacle, and having a cord that plugs into whatever device you're using. If you come from the US with a device using a power supply of this type rated for 110V, simply buy the 220V equivalent here in Ireland. They are relatively inexpensive and work exactly like their 110V cousin. Make sure to bring the 110V power pack with you so you can be sure of buying exactly.

The electricity supplied by the ESB enters through your electric meter and then works its way towards your electric panel. Generally speaking, the Electric Company takes responsibility for your service up to and including your meter. From the meter and onward throughout your home they consider as being your responsibility, and will rarely have anything to do with any problems developing from there, including your electric panel. For electrical problems in your home they will usually advise you to call an electrician.

The three basic components in your electric panel are the main breaker - MCB (MCB = miniature circuit breaker), main GFI (Ground-fault Interrupter), and all the breakers (MCB) that control all the different lines in your home. Of course you may have various other components such as a contactor, timer, switch, etc, but we'll discuss some of those components later.

MAIN BREAKER
Coming from the electric meter, the main line is then connected to the main breaker. Some older homes may have their main breaker located somewhere near the electrical meter (separate from the electrical panel), even though the location of the meter may be a considerable distance from the electric panel. In most cases though, the main breaker is located in your electrical panel. If the service you are getting is single-phase, then the breaker will look like most others in the panel but having a higher current rating.



Single-phase service comes as 25A or 40A. 25A is no longer available and will mostly be found in the older homes, unless they were upgraded at some point. If you have a 3 phase service, then you will have what looks like three breakers with their levers barred together. 3 phase service starts at 25A, and continues to 40A, 63A, 80A, 100A…and onward. The purpose of the main breaker is to limit the amount of current that the panel, as a whole, takes from the ESB, and to protect their fuses.

GROUND-FAULT INTERRUPTER
The next item that you will find in your panel is the "GROUND-FAULT INTERRUPTER". This is known by many names including GFI, GFCI, RCD, ELCB, the "safety device. The single-phase GFI is twice as wide as a standard breaker, has either an up and down lever, sideways lever, or turning dial type lever. It also has a test button. The 3 phase GFI looks the same as the single-phase one, except it's bigger (the size of 4 breakers). There are some old types of single-phase Elcb's around that are the same physical size as the 3 phase. Most companies don't make the large type anymore.



How much current you use, but rather cares that there is no leakage from the line. So for example, if you would stick your finger into an electrical outlet (not advisable), the GFI would sense that not all the current is going through the wires, but rather leaking out to your body. It would then trip immediately. Although you may have received a bad shock, the GFI would have probably saved your life. The one thing that's common to most Elcb's is the "test" button found somewhere on the device. This button will cause the device to trip. It is good practice to push the button once every couple of months in order to make sure the GFI is working properly. If the GFI does not jump when the button is pushed, a qualified electrician should be called to investigate and possibly replace the GFI.

VARIOUS LINE BREAKERS (MCB)
The rest of the breakers are for the various lines around your home. These lines can be distributed in many different ways, depending on the design, and the electrician who did the work. The standard sizes used in Ireland are 10,16,20,25 and 32amps, although any size can be used depending on the purpose. There are certain lines in your home that according to the Irish standard MUST be designated lines. This means that only one device is on that line and nothing else. Such lines include the electric water boiler, the washing machine, the dishwasher, and the oven.

If your service is 3 phase, then it is possible that you have one or more 3 phase line breakers either supplying electricity to a secondary panel, or to a 3 phase device (air conditioner, oven, etc). These line breakers have two purposes. The first purpose is to protect the wires in the wall so that they don't burn up. In order for them to accomplish this they must be properly rated for the wires used on that line, otherwise they can't do their job. The second purpose is to isolate a line, which is shorting or is being overused, by jumping before the main breaker. This prevents a total shutdown of all the electricity in your home, with only the particular faulty line tripping. Sometimes though, if you have a very strong short, it will go through both the line breaker and the main breaker, causing everything to go out. The following are some other components that can be found in certain panels.

CONTACTOR
In essence, a contactor is a switch, having 1 or more contacts, that operates with the help of an electric magnet which closes and opens the contacts. The contactor is mostly used in conjunction with a timer or another device that will regulate the current causing it to open and close.



The contactor is used for many purposes. One such purpose is to switch on and off a higher current that would normally burn out other, more fragile, devices that were not built to handle such currents. Many times the contactor is installed deep inside the electric panel, where it remains out of sight until the panel is opened up.

TIMERS There are many different types of timers around. There are simple spring type timers that you set for a certain amount of time, and when that time passes, it shuts off. There are timers that have a dial, where you set certain times for the timer to switch on and off. There are digital timers, programmable timers, and dual timers. In most homes in Ireland, timers are used to operate devices around the home (such as lights, air conditioning, fans, etc. Timers are also frequently used to operate certain devices when nobody is home.

SWITCHES Switches in an electrical panel operate exactly like the average switch found around your home. They are used to switch things off and on manually. Many times they look very similar to MCBs, but they are not MCBs, and will NOT protect any line or trip for any reason.

If your question is still unanswered, please feel free to contact us!