To prevent running separate lines to a machine, what can be used to step up the control voltage?

Utilizing a control transformer is an effective method to step up the control voltage for powering a machine without the need for running separate lines. Control transformers are specifically designed to provide precise voltages for control circuits, allowing for enhanced functionality and safety. They step down higher primary voltages to lower, more manageable control voltages, ensuring that the control components operate correctly and safely.

This type of transformer is essential for control applications because it typically includes features such as a secondary winding that delivers the desired lower voltage specifically for control devices, thus facilitating efficient operation and avoiding voltage drop issues that might occur with regular transformers.

In contrast, while a standard transformer can also adjust voltage levels, it might not be tailored for the specific needs of control circuits. Voltage regulators are used to maintain output voltage at a constant level regardless of variations in input voltage or load conditions, but they do not inherently step up or down voltage, lacking the specific voltage transformation features of a control transformer. An isolation transformer provides electrical separation to enhance safety and protect sensitive equipment, but it also does not serve the purpose of stepping up voltage.

Thus, the most appropriate choice for stepping up the control voltage while preventing the need for separate lines to a machine is the control transformer.