The modular spray system ensures accurate, precise placement of the liquid being sprayed to minimize waste. The system provides automatic on/off control of electrically- and pneumatically-actuated spray nozzles and offers greater precision than manual operation or devices such as solenoid valves. The automatic control of air and liquids provided by the system yields many benefits. Proper flow and drop size eliminates quality control problems due to uneven application and improves worker safety by minimizing misting and overspray. Accurate spray placement on the target reduces the use of costly chemicals and coatings and reduces mess and maintenance time. The system is self-contained and compact. It is approximately 2.5-feet-tall and 1-foot-wide for easy integration into any operation. Set-up of the unit takes just a few minutes. Operators can be deployed to other tasks once the delay time, spray time, repeat time and duty cycle have been set. The system is available in three configurations so users can select the needed level of control: liquid pressure only, liquid and atomizing air pressure or liquid, atomizing air and fan air pressure. The unit is ideal for use in lubricating, coating and marking applications and can be used in small- or full-scale operations.