139-DO-FLC

About the 139-DO-FLC

The 139-DO-FLC Motor Protection Relay is one of the relays with a different output option than the standard option; the output associated with this mode is a full load current, which is denoted by the FLC acronym at the end of the part number, operates on a milliamperage of four to twenty. The D in the order code indicates what type of supply power is needed to operate this relay without any faults occurring. The power supply for this model is one hundred and twenty volts of alternating current.  

One feature of this relay is the start timer. The start timer on this model is used with an induction motor which draws an inrush current while moving up to the desired speed for starting which is usually greater than the full load current. When starting the timer across the line the range is typically between five and seven times the standard running current. When setting the start timer it is best that the true run-up time is measured and then specified by the locked rotor times as well as the continuous number of starts allowed by the manufacturer. It is best to set the control of the start timer on the 139-DO-FLC relay to a timer that will be less than the max locked rotor time but is still greater than the overall time needed for the max number of back-to-back starts allowed. 

Memory lockout is another feature used with the 139-DO-FLC relay. There are several start conditions that can trip memory lockout, these conditions are overload and start trip conditions. For more information on the memory and memory lockout of this device refer to the attached manual.