The Model 663 Pump Down Control, part of the 600 series line of instrumentation controls, is designed to monitor and maintain liquid levels. A user-provided 4-20mA current loop represents the liquid level. The HIGH ADJUST setpoint, and the LOW ADJUST setpoint, are field adjustable. If the input rises above the high setpoint, the PUMP DOWN relay energizes, and remains that way until the input falls below the low set point. Top-mounted LEDs on the Model 663 show system status. The PUMP DOWN LED turns ON when the input is above the high setpoint, and goes OFF when the input is below the low setpoint. The HIGH ALARM condition indicator turns ON if the input rises to 10% above the high setpoint. The HIGH ALARM condition then resets when the input is again less than 10% above the high setpoint. For proper operation, the high setpoint must always be set above the low setpoint. An INPUT LOOP ERROR LED turns ON if the input is outside the 4-20mA range. A Time Mark Model 650 Loop Power Supply (or equivalent) is required to provide the 24 VDC operating voltage. Also, a Time Mark Model 672-15 Pressure Transducer (or equivalent) is required to provide the input signal.