Live wires and parts are the conducting parts that are energized, like wires, circuit breaker connecting parts and overhead power lines.
I have to work with live parts in many cases, such as check and inspection of a power circuit. I have to make tests and perform measurements without isolating power. How come I check a faulty circuit with no power.
But, I know exactly how to do such thing, I never miss with electricity!
Live parts require precautions and safety culture. If you don’t have enough experience and training, never work on live wires and parts.
I will share with you my experience about working on live wires and parts in this article.
How do electricians work on live wires?
Electricians work on live wires with proper safety precautions and training. They don’t touch it by hands, and don’t touch live wire with the neutral.
I turn off electrical power before I work, but in many cases I have to work while power is on to make troubleshooting for a circuit or a device.
In this case, I work with great precautions, I sit on an isolating chair, and tell all persons around me not to touch me to keep my body isolated.
I try my best to stay focused, not to touch the exposed live wire by hands, not to touch live wire and neutral one and only use insulated tools.
Professional electricians have to work on live wires without switching off the power, as it may be the job demand.
They make sure that they are not grounded and providing the path for passing the current.
So they find appropriate ways as far as dealing with hot wires is concerned. Precautions including but not limited to:
- Rubber and leather made insulating gloves for high voltages and only leather made for low voltages
- Not use Metal ladders
- Not use metal tools
- Wearing Rubber safety shoes
- Usage of Insulating mats of rubber during standing and leaning
- Safety Glasses
- Insulating arm sleeves of rubber for the high voltage
- Using bucket truck for OHTL.
By using these above precautions and wearing these protective equipment, they can minimize the risk of electrical hazard.
But as far as a common man is concerned, he should not do work on energized circuits, as electricians are experienced and trained personnel.
A common man should de energize the system and then there should be any working on it.
I have written a detailed article about Electrical hazard and safety, you can find it here for more information.
Will I get a shock if I touch a neutral wire?
Under quite normal situation, you will not get a shock when you touch the neutral wire. But when neutral is broken at some point, you will get a shock.
In electrical distribution system, a neutral wire is considered as a point that carries no current during the normal circumstances, but in the times of fault, it carries fault currents.
There is a difference between ground wire and neutral wire. The main purpose of the neutral wire is return path and main purpose of ground wire is to provide safety to operator.
One should not touch the neutral wire without switching off the power as you don’t know it is cut into two pieces and you are filling the gap, obviously if this happens you will face shock.
Neutral wire can carry some current if system is unbalanced, means there can be the unbalanced load or some unbalanced fault in the system.
In real world, an electrical system is never completely 100% balanced. There is pretty much good chance for having some sort of current in the neutral wire, so it’s a good approach not to touch the neutral wire.
How do electricians wash live overhead power lines?
Cleaning of overhead transmission line is not that much needed but cleaning of insulators is pretty much important.
Any dirt or the dust that falls on the overhead lines is usually of limited thickness and it does not the affect the electricity flow in any meaningful way.
But cleaning of insulators is required that support the conductors.
When they are contaminated, they should be clean with the pressure washer like a car wash. This can be done when transmission line is energized or de energized depending on the utility operational practices.
Distilled water should be used when line is energized. The spraying water should be free from the minerals and salts as it reduces the risk of flash back to the nozzle.
In some countries they utilize the helicopters for this purpose.
High pressure deionized water is used by the personnel who performs the washing of high voltage insulators on the power transmission lines.
Non-conductive water having well below the conductivity is used. The water’s high velocity carries off the any contamination material that are on the surface of the insulators and thus stops the flashover to the ground.
Also the worker wears his rubber gloves and use isolated bucket truck. By this way, he ensures his safety during OHTL live washing.
Measuring the water conductivity is done each time they fill the washing tanks. Every single day.
How do they repair live power lines?
Hotlines repair is another name of live line working. Usually the repairing is done without cutting off the power, so precautions should be adopted by the linemen.
No matter how much experienced you have in this field, you should adopt the precautions techniques because life is precious.
This task should be handed over to a man who is quite responsible and serious person as no safety equipment in the world can save you if there is negligence involved.
Below mentioned techniques are helpful in safe repairing of the live power lines:
Hot hand method:
A specialized suit should be worn by the lineman. Maintain the same voltage level between the human bodies performing the repairing work and the power lines and tools, it is most commonly used method.
By using a helicopter or some platform, lineman is raised to the same voltage level. It is pretty much important that technician should be isolated other objects having different potential, so that no it does not cause any current to flow.
All grounded equipment must be removed or insulated.
As lineman approaches the power line, with the use of conducting wand, small arching is created for electrical bonding between hot line and worker.
Worker is safe from shock because he and live line are at same potential.
Usage of insulating gloves:
The worker uses insulating gloves and performs the repair work with direct contact to the live parts.
Method of Hot stick:
In this method, a hot stick is used to maintain the gap between the live line and the worker. This prevents the occurrence of the electrical arcs.
Maintaining a safe gap is essential with a hot stick as surrounding air can become conductive sometimes.
Required tools are attached to the stick and these are made of insulating material and it provides safety to linemen during repair work.
How do electricians work on overhead lines
Is electricity bucket truck insulated?
Yes, bucket truck is electrically insulated.
A bucket truck is that type of truck which is equipped with hydraulic boom that carries a large bucket for raising the electricians to elevated and normally inaccessible areas.
For electricity related tasks, we use insulated bucket trucks because in this specific case not only elevation is required but also safety from the electricity hazard is essential.
The bucket and the boom are insulated parts of the bucket truck. Coating of dielectric fiberglass prevents the flowing of electricity through the boom.
This also prevents the damaging of equipment and provides safety to the workman from electrocuting. Usually, a boom has three insulating areas.
Three areas include area in lower boom, area in upper boom, and area in bucket liner. These all areas have different ratings of insulation. Bucket trucks can be used to work on the very high voltage power lines.
Bucket liner provides safety inside the liner means a person gets safety who is standing in it. When electricity touches the liner, it becomes useless for anyone or anything inside the liner.
Upper boom insulation section helps to stop the flow of electricity from the tip of bottom through the elbow of boom.
Lower boom insert provides the insulation between chassis of truck and elbow.
Can you touch a live wire when you wearing a safety boot?
Yes, you can but you should take care of certain things before this.
Make sure your safety boots are made of quality rubber. The properties in the rubber prevents the electrons to move freely.
The electrons are bounded tighter and this makes the rubber a very good insulator.
Rubber is a pure insulator but only if rubber is pure and no tears and holes should be there.
You boots must be completely dry. They should not have metal studs.You should also wear the quality rubber gloves when doing repair work on the transmission lines.
When you wear the rubber shoes, then you are not giving the path to current to flow to the ground.
Otherwise, if one touches the live wire without wearing the rubber shoes, current will pass through the body and he will get shock.
Also take care that surface should be dry on which you are standing while touching the live wire.
Only wearing of safety rubber shoes and protective gloves is not enough, also make sure that no other part of your body should touch the other objects.
No other person should touch while you are wearing rubber shoes and doing the work on the live wire.
When can I touch a live wire without being shocked?
Although I recommend never to touch live wires, Non electricians or a common man can touch the live wire with insulated screwdriver or pliers, but make sure the screwdriver has quite well insulating handle and its insulation voltage is suitable for the circuit voltage level.
As an extra precaution before you touch a live wire with a screwdriver, tools or a pliers is to keep your body isolated.
It means to make sure your body is not with a contact with any grounded parts, like walls, floor and any person who is in touch with any grounded parts.
But, if you touch the metal part, then most likely you will get a shock. Also, non-electricians should touch the live wire with the insulated like rubber gloves, so everything is perfect.
Try to cut off the power while doing operation, but if it’s not possible, then you should deal this situation with protective gloves and screwdriver having insulating handle.
You will not get a shock if you wear the rubber shoes, because you are not giving the path to current to flow from your body to the ground.
But make sure nobody touches you during this time, as if somebody touches, you are actually providing the path to the flow of current despite wearing shoes, so take care of this aspect too.
Gloves and hands should be pretty much dry when you touch the live wire. Also make sure you are standing on the dry ground while touching the live wire.
There should be no tear or holes in the gloves. Protective gloves should be of pure insulating material.
Existence of the protective electrical equipment is important but availability of high quality protective equipment is more important than just mere existence.
Can you touch a live wire with rubber gloves?
Yes, we can touch live wires with electrical insulation rubber gloves, if and only if they are tested and certified for working on the voltage level of the live wire.
Not all rubber gloves are suitable for electrical live work. And not all electrical gloves are suitable for all voltages.
For example, a low voltage gloves should be tested for circuits with voltages up to 1000 V, these of course are not suitable for medium or high voltages.
If you touch a live wire with a rubber gloves with lower voltage levels you will, for sure, get a shock depending on the circuit voltage level.
A rule of thumb when using rubber gloves for electrical live work, is to test it before every single use, keep them dry and make sure it has no cuts.
Rubber gloves are not enough to protect you against electrical hazard, you should use insulated tools, wear the right PPE for the job and be aware of all electrical hazards and safety precautions for the task.
As an example, we have a team for live maintenance work and repairs, the worker does the following precautions:
- Wears medium voltage rubber gloves
- Isolate his body using an insulated bucket truck
- Use only insulated tools.
- Test the gloves every single day.
- Keeps the gloves dry.
- Use insulation blankets for insulating other phases and earthing wires. i.e he only allowed to touch one phase.
Can you cut wires that are live?
You should not cut the live wires. Yes it’s possible, but as a matter of care you should cut it after switching off the power.
You don’t know where this live wire is transporting the power. Use the insulated handles if you are doing this, but at a certain point, they also get live.
Another danger in this situation is that you are actually exposing the live wire by removing its insulation and it’s always a bad idea.
At the instant your cutters cut the live wire, cutter are also live, so if they don’t have the insulating handles or you accidentally touches the metal part then you will get the shock.
It is recommended not to do it by yourself but by an electrician as he has hands on experience and his hands works that way that is feasible.
Electricians do this because they are experienced personnel and they know how to cut the wire with the dry screwdrivers having insulating handles while not touching the wire with the hand.
They wear safety boots and thus not allowing the current to flow from their body. They make sure they are not grounded.
They use the insulated tools when they cut the live wire. They wrap the some insulating material on the wire after cutting, so that it is not exposed.
Also they know the value of the voltages that they can handle with certain precautions.
One more thing to take into account is, never cut two live wires together at once, or one live wire and the neutral, this can cause a short circuit and explode.
For more information about electrical short circuit, read my article what is electrical short circuit and why is it dangerous on my electrical site electrical4uonline.
Why do electricians work with one hand behind their back?
One get shocked only when current passes through the body. So, electricians work with one hand behind their back because they think in this way they are not providing the path to the current flow.
This is not hard and fast rule that hand should be on behind the back, the point is it should be away from the conductive material, it can be in the pocket or anywhere else.
This practice reduces the risk of electrical shock as per the practice of electricians.
They think that they have two big electrodes hanging to the shoulder.
To avoid setting up the path for conduction through the human body, they keep on electrode out of two behind their back or keep it in the pocket.