The regulator monitors the exciter excitation current as a function of the alternator output voltage. Simple in design, the alternator with shunt excitation has no sustained short-circuit capacity. Voltage regulation: around +/- 0.5%. Voltage supply/sensing range: 85–139 V (50–60 Hz). Rapid response time (500 ms) for a transient voltage variation amplitude of 20%. Voltage setting P1; Stability setting P2. Initial potentiometer settings: 1) P1 potentiometer (AVR voltage adjustment): fully anti-clockwise. 2) Remote voltage adjustment potentiometer: center position. Run the alternator at its rated speed. If the voltage does not increase, the magnetic circuit should be remagnetized (refer to section 23). 3) Turn the AVR voltage adjustment potentiometer P1 slowly until the rated output voltage is achieved. 4) Adjust the stability setting using P2. 5) Sealed potentiometer P3 is factory set at 48 Hz for 50 Hz and 58 Hz for 60 Hz. Material: plastic. Color: black. Package includes: 1 x Automatic Voltage Regulator. Only the above package content is included; other items are not. Note: Lighting and display differences may cause slight color variations between the image and the actual item. Measurement may vary by +/- 1–3 cm.