This manual covers the National Vendors Pre-PIE Snack and Refreshment Center Vending Machine, a series of electric-powered units designed for efficient product dispensing. These machines are engineered with motor-driven spiral or rod rotation mechanisms, actuated by electronic solenoids and motors, to ensure reliable product delivery. The units feature keypad or electronic selection buttons and are compatible with various payment systems, depending on their configuration. Their robust construction, with typical dimensions and weights that vary by specific model, makes them suitable for a wide range of commercial and public environments.

The purpose of this English-language troubleshooting sequence of operation manual is to provide essential technical information for technicians. It focuses on the electronic operations and the vend process, offering a step-by-step analysis methodology to diagnose and resolve issues. This documentation package is intended to guide users through the sequence of operation, enabling them to effectively troubleshoot electronic diagnostic codes and perform periodic sensor and selection calibration. By detailing the machine's operational logic, this manual aids in maintaining optimal performance and longevity for models 147, 148, 247, 248, 461, 462, 474, 475, and 476.