Feature: 1. Self Excited Function: The alternator with shunt excitation is self excited with an R230 automatic voltage regulator. 2. Monitoring of Excitation Current: The regulator monitors the exciter excitation current as a function of the alternator output voltage. 3. No Sustaining Short Circuit: Very simple design, alternators with parallel excitation have no sustaining short circuit capability. 4. Great Replacement Parts: The automatic voltage regulator board is professionally designed for a great fit and finished for easy assembly. 5. Premium Material: The R230 AVR automatic voltage regulator is made of high grade ABS material for stable and dependable use. Specification: Item Type: R230 AVR Automatic Voltage Regulator Material: ABS Voltage Regulation: Approx. ±0.5% Power Supply Range: 85-139 V Potentiometer for Voltage Setting: 1000Ω/0.5W, Minimum Setting Range ±5% Use: Voltage Regulator Gross Weight: Approx. 325g/11.5oz. Package List: 1 x R230 AVR Automatic Voltage Regulator1 x Manual Note: In order to reduce the loss of customers, special tips! If you need to magnetize the generator set, please remove the AVR board and then magnetize it! In order to prevent the AVR board in the magnetization process, due to improper super work lead to fried tube burn board, are not eligible for warranty and return service! (Fried tube burn board: PCB circuit board large area fried burned bad, basically is not repairable, and repair is also very troublesome)