How to Wire a 230 24 Transformer

A transformer is a device that converts an AC (alternating current) voltage to a DC (direct current) voltage for use in circuits such as push buttons, thermostats, and other devices. A 230 24 transformer has a laminated iron core with one or more windings of wire and may have a center tap, two outputs, or multiple taps for different voltages. It is a useful tool to have when working with electrical control circuits for air conditioning, heating or refrigeration systems.
How to wire a transformer
The first step in wiring a transformer is to remove all electrical power to the device it will be used to power. This usually means shutting off the circuit breaker or pulling the fuse that supplies the device with power. Then you can mount the transformer to a firm surface using the provided screws or enclosure.
Next, inspect the wires connected to the transformer. Most have four wires–two black and two more that are yellow, green or blue. The two black wires are for the 120 VAC input and the yellow, green or blue wires are for the 24 VAC output.
Connect the appropriate wires to the primary and secondary coils on the transformer. This may entail cutting the insulation off of each wire with the aid of wire strippers or bending the ends of the wires so they can fit over the end of the terminals. The correct terminations must be chosen as the wrong terminations can cause a short circuit and burn up the transformer.
Consider the load capacity of the transformer and choose a wire size that limits the voltage drop between the controller and the transformer. Voltage drop can result in erratic network problems or controller failure. Limit the distance between each transformer and its connected controller to 5% or less for each wire length and use a gauge of wire that will limit the voltage drop at the controller to no more than 1.2 volts AC.
How to wire a transformer in a delta configuration
The most common way to wire a transformer is a delta configuration where the input and output are both on one side of the transformer. This allows for a wider range of output voltages and gives more flexibility to the use of the transformer.
Another way to wire a transformer is in a wye configuration where the input and output are on opposite sides of the transformer. This provides a narrower range of voltages and is more expensive than a delta configuration.
Some specialized transformers are designed with multiple taps for different voltages which can be a good choice when the desired voltages are on the low end of the spectrum. These are often called “autotransformers” and they are easier to use than step down transformers for many applications.
Choosing the right transformer for your application can be difficult as it requires a lot of information about the desired output voltage, how much current will be needed and the size of the wire that will carry that current. You should consult the manufacturer for advice before selecting a transformer.