Time Mark Model 661 Material Level Controller

The Model 661 Alarm Controller is part of the 600 Series Instrument Control family,designed to monitor and maintain measurable applications such as liquid level,temperature,pressure,flow,etc. The user-supplied 4-20mA current loop represents the measurable application and provides output connections for signaling alarms. Two set points,high adjustment and low adjustment,are field adjustable. If the input is between the two set points,the relay is energized. If the input is above the high setpoint value,the high alarm relay de-energizes to provide a trip condition. This trip condition will automatically reset when the input drops below the set value. If the input is below the lower limit of the set value,the low alarm relay is de-energized. When the input rises above the set value,the trip condition is reset. The Model 661 is equipped with a top-mounted LED to indicate trip status. The high alarm or low alarm LED goes out in the tripped state. If the input is outside the 4-20mA range,the input loop error LED lights up. A time-stamped Type 650 loop power supply (or equivalent) is required to provide DC operating voltage. A Type 672-15 pressure sensor (or equivalent) is required to provide the input signal.