Transformers

A transformer actually transforms

voltage

If you're having problems with electricity

a bad transformer may be responsible

What are some appropriate steps to troubleshoot an inoperative transformer?

1. Check that line and load connections are properly made and that appropriate jumpers and/or tap settings are in accord with nameplate instructions. 2. Measure input voltage to insure that voltage is within 5% of nominal rated voltage or tap setting 3. If input circuit protection opens while energizing transformer, make sure fuse or circuit breaker is a minimum 1.25 x full load input current rating of the transformer. 4. If the transformer can be energized, measure output voltage with no load on transformer to insure that voltage is within tolerance. 5. If a neutral is derived on the load side of the transformer, insure that neutral ground bonding is accomplished in accord with National Electric Code or local code requirements. Failure to ground neutrals is often the cause of unusual voltage measurements to ground.

How to Troubleshoot Electrical Transformers

1.Test the transformer for a primary winding to secondary winding short. 2. Test the transformer for winding to lamination shorts. 3. Test the primary winding and the secondary winding(s) for continuity by placing the DMM probes across each winding's terminals. 4. Check the transformer's output voltage.

How to use a Multi-Tap Transformer

Connect one wire to the 12V tap at the transformer; connect the other wire to the white (common) tap. Measure the voltage at the first light using a voltmeter. Example: 11V Subtract the measured voltage from 12. This equals your voltage drop. Example: 12-11V = 1V Add the voltage drop to 12. This is equivalent to the voltage tap you should use. Example: 12V + 1V = 13V Move the wire from the 12V tap to the calculated voltage tap. Leave the other wire connected to the white (common) tap.

Control transformers insulated

Control transformers incorporate high-quality insulating materials. This insulation is used to electrically insulate turn to turn windings, layer to layer windings, primary to secondary windings and ground. Control transformers are vacuum impregnated with VT polyester resin and oven-cured, which seals the surface and eliminates moisture. Filling the entire unit provides a strong mechanical bond and offers protection from the environment.

In three-phase motors, in order to provide more starting torque, the stator would be connected in a __________.

Delta configuration

What are Control transformers are designed for?

Designed for industrial applications where electromagnetic devices such as relays and solenoids are used, the control transformer maximizes inrush capability and output voltage regulation when electromagnetic devices are initially energized.

Applications in Automobile Industry:

Electric vehicles are the up and coming automobiles to create buzz in the market. Their batteries are charged by a power source. However, custom transformer is needed to monitor and control the voltage of electricity that is being used for charging the batteries. Advanced technology and innovations have led to development of "smart transformers" that can be used for charging multiple electric vehicles at a time.

Application in the Electrochemical Industry:

Electrolysis of elements like copper, aluminum, zinc or chlorine is essential in various electroplating processes. Rectifier transformers are specially designed to carry out such electrolysis process efficiently.

Describe the relationship between input and output current, voltage, power, and turns ratio for a control transformer.

Input and output current are inversely related with transformers. If the current is being stepped up in voltage the current will reduce. If the current is stepped down the voltage will decrease but the current will increase. Turns ratios determine how the voltage will be changed in the transformer. If the output coil is winded with twice as many turns as the input coil the voltage will be double.

Power transformer formula

IpVp = IsVs

Turns Ratio Formula (Autotransformer Law):

Ns/Np

7 WAYS TO TELL WHEN A TRANSFORMER IS BAD

PERFORM A VISUAL INSPECTION Performing a visual inspection of your transformer is key. Sometimes, you'll be able to see things right away that indicate a problem with the equipment itself. If you notice any bulges along the exterior, for instance, or if you see any burn marks, it's a good indication that the equipment needs to be replaced. If you see visual damage, don't even try to test it! Instead, call a professional to remove the old unit and install a new one that works. Overheating or a power surge can cause substantial damage to the unit. Those circumstances produce visual deformities and render the equipment useless. CHECK THE SCHEMATIC CIRCUIT Understanding how the equipment works is critical when making repairs. The unit's schematic layout shows precisely where all the wiring is located. Looking at a schematic, you can easily see how all parts of the circuit are connected. The schematic will be included either as part of the owner's manual or available online depending on the manufacturer and the unit's age. FIND THE INPUT AND OUTPUT The inputs and outputs of energy flow into and from the transformer are essential to find. The electrical field that produces energy will be the point of energy flow into the unit. On the other end, the outputs are circuits that get power from the magnetic fields. They are connected to secondary connection points from the equipment. CHECK THE VOLTAGE Once you determine that the unit is safe and has electricity flowing into and out of its connection points, you'll want to check the strength of the electricity. This helps you determine whether or not the unit is faulty. You can check the voltage by checking the top center tap. There are two top taps that you can look at. If there is power going to the unit, check for a bad connection from the power connection block to the unit itself. INSPECT THE METER The meter reading on your unit can also indicate whether or not it is functioning properly, and if it is, to what degree. The unit should provide either 240 or 280 volts of AC current. This current should lie along the two outer wires near the transformer's bottom. If you don't see any voltage, the problem likely lies with the unit itself and it will have to be replaced. EVALUATE THE POWER A bad transformer will have weak power or none at all. If there is power to the unit, it may not be faulty. However, if there is little or no power going to the unit, it may need replacement or repairs. A simple way to check the power is to turn the unit off and on again. Alternatively, you can continue moving back on the line to measure the voltage. Keep moving backward until you get a voltage reading. NO VOLTAGE If there's no power, there may be no voltage at all. By checking the voltage points, you can quickly determine if voltage is the issue. If there is no voltage or weak voltage, the problem may have several root causes. One is the control. The control board can also fail. Either way, you'll need to replace the faulty unit.

Applications in the Steel Manufacturing Industry:

Steel manufacturing plants rely on the delivery of high currents over a varied range of voltages for their functioning. This requirement is fulfilled by specialized high voltage transformers. Such transformers can sustain the extreme dielectric, mechanical, and thermal constraints of a steel furnace.

Transformers are usually rated in units called

Volt Amperes

potential is the same between any two lines

Wye configuration

transformer

a device that increases or decreases the voltage of an alternating current

Control transformers

are generally used in an electronic circuit that requires constant voltage or constant current with a low power or volt-amp rating. Various filtering devices, such as capacitors, are used to minimize the variations in the output. This results in a more constant voltage or current.

voltage transformer

changes the voltage from one circuit to a different voltage in another circuit by means of induction and an alternating circuit

The transformer

either reduces (steps down) or increases (steps up) the voltage to match the requirements of the control circuit.

Transformers

have varying currents, which in turn creates a varying magnetic flux that produces an electromotive force around the core.

Power transformer meaning

input power = output power

A transformer

is a device that uses the principal of electromagnetic induction to transfer voltage and current from one circuit to another. The transformer uses a primary coil that's connected to line voltage and a secondary coil that provides the output voltage.

A control transformer, (also known as an industrial control transformer, or a control power transformer, or even a machine tool transformer),

is essentially an isolation transformer that provides excellent voltage regulation. A control transformer is very often designed to produce a high level of secondary voltage stability during brief periods of overload condition, otherwise typically known as "inrush current". Most transformer products control power from higher to lower voltages. Transformer suppliers who provide service support solutions for control transformer applications.

if the primary of a transformer were connected to a dc power source, the transformer would have a voltage output

only while being connected or disconnected

Power transformer

power in primary coil = power in secondary coil

turns ratio

ratio of the number of secondary windings to the number of primary windings

A common application of mutual inductance is found in a device called a

transformers

cause

trouble shooting incorrect voltages, wiring issues, odd or weird voltages to ground, or inoperative transformer