Count the turns ratio of the windings. The voltage ratio is equal to the turns ratio. The current ratio is equal to the inverse of the turns ratio.
For instance, a power transformer with a 10:1 turn ratio (primary to secondary) running on 120V will produce 12V. If it consumes 1 ampere from the input, it will provide 10 amperes to the output.
For an ideal transformer, the voltage ratio is the same as its turns ratio.
For an ideal transformer, the turns ratio will be the same as the voltage ratio.
Secondary voltage / primary voltage
A transformer's voltage ratio is the ratio of its primary to secondary rated voltages and, for an ideal transformer, is the same as its turns ratio.
The voltage ratio is equal to the turns ratio for an ideal transformer.
For an ideal transformer, multiply your primary voltage by the transformer's turns ratio: Vs = (NS/Np) x Vp
Turns Ratio = (Primary turns / Secondary turns) To calculate the turns ratio you have to actually know the number of turns or wraps on the primary and secondary coils. Nobody knows that usually the manufacture of the transformer doesn't even know. So what you can use as and equivalent is to calculate the voltage ratio. So what you typically need to look for is the Input voltage and divid it by the output volatge. Usually that would be as follows; (Primary Voltage/Secondary Voltage) = Voltage Ratio
It depends on the turns ratio of the transformer.
A current transformer is a transformer that takes a ratio of primary current, and delivers this ratio to the secondary. The voltage across the primary will be insignificant, and the voltage across the secondary is dependent upon the resistive burden put across it (since the current is a constant ratio of the primary current). A voltage transformer is a transformer that takes a ratio of primary voltage and steps this down to a specific secondary voltage. Primary current is typically very small and secondary voltage is typically very small. A power transformer is a voltage transformer that is designed for "large" primary and secondary currents.
By changing the turns ratio of the transformer. a higher turns ratio will cause a greater increase in voltage / decrease in current.
By determining the transformer's primary and secondary phase voltages. The ratio of the primary phase voltage to the secondary phase voltage will be practically the same as its turns ratio.For example, in the case of a delta/star connected transformer, the primary phase voltage will be its primary line-to-line voltage; it's secondary phase voltage will be its secondary line-to-neutral voltage.
A 'step-up' transformer's secondary voltage is higher than the primary voltage. This 'voltage ratio' is (for an 'ideal' transformer) the same as its 'turns ratio'. The secondary current is determined by the load, which then determines the primary current -the current ratio being equal to the inverse of the turns ratio.
It's approximately the inverse of the voltage- or turns-ratio:
In any transformer, step up or step down voltage is a function of turns ratio. For instance, if the secondary has twice as many turns as the primary, the step up voltage is a factor of two.
You establish what the ratio of the transformer is and then apply the ratio in the same proportions to the voltage.
A current transformer is a donut (toroidal) shaped transformer. You use it to measure current (expressed in amperes). You run your wire to be measured through the transformer and it produces a variable output based on the current.A potential transformer is basically a high ratio transformer that is used to measure voltage on high-voltage lines. For example: They will use a 10:1 ratio potential transformer to convert 4160v to 416v. Then they can measure this lower voltage with a meter. The meter then applies a user programmed multiplier (10) to this number to calculate the voltage.
The secondary voltage of a transformer with a turns ratio of 5 to 1, and primary voltage of 200 is 40. (5 to 1)
The ratio of output windings to input windings determines the ratio of output voltage to input voltage. The ratio of current is the inverse.
Strictly speaking, a transformer's voltage ratio is the ratio of its primary to secondary rated voltages*, regardless of whether it is a step up, or a step down, transformer and, for an ideal transformer, is the same as its turns ratio.[*Often, however, turns ratio is expressed in terms of high-voltage:low-voltage, e.g. '10:1', regardless of whether it is step down or step up.]
The primary current on a loaded transformer depends on the secondary current, which is determined by the load. So, if you know the secondary load current, then you can use the turns ratio of the transformer to determine the primary current:Ip/Is = Ns/Np
Take the VA of the transformer and divide it by the output voltage.
A transformer has an alternating field in the magnetic core with a predetermined amount of flux that gives a well defined number of volts per turn, or turns per volt for low-power transformers. Therefore the voltage of a winding is proportional to the number of turns. The turns ratio is therefore equal to the voltage ratio of the transformer.