B-Line Magnetically Latched Lighting Contactor

The B-Line A202K3BA is magnetically latched, meaning the coil is energized only momentarily to change state and the contacts stay put mechanically after that. An electrically held contactor draws coil current continuously for as long as the load is on, which means constant coil heat, coil hum and a dropout every time control power is lost. Latched operation suits lighting panels switched by a time clock, photocell or momentary pushbutton, and keeps the lights on through a control-circuit interruption. If you want the load to drop automatically whenever control power fails, you want an electrically held contactor instead, not this one.

Two. It is a two-pole contactor, so it switches two poles at 100A each. For a 120/240V single-phase panel that covers both ungrounded legs; for a three-phase lighting load you need a three-pole unit instead. Count the conductors you actually have to break before you size it.

The published rating on the B-Line A202K3BA is 120V at 60 Hz, which is the control coil rating, so your time clock, photocell or pushbutton control circuit needs to be 120V 60 Hz. The 100A figure is the contact rating for the switched lighting load. Feeding a 277V control signal into a 120V coil will destroy it, so verify what the clock output is before wiring.

Yes, and that is the normal application. Because the A202K3BA is magnetically latched it wants a momentary contact closure rather than a maintained one, so pair it with a time clock or photocell control that provides momentary ON and OFF pulses at 120V, 60 Hz, or wire a two-button momentary station. A maintained-contact clock output holds the coil energized continuously, which is not how a latched contactor is meant to be driven.

The A202K3BA carries a 100A rating per pole, which covers most commercial site and parking lot lighting banks. Size it against the actual connected load, not the breaker: lighting is a continuous load, so the contactor and the branch circuit should be picked at 125 percent of the connected amperes. HID and older magnetic ballast loads draw heavy inrush, and tungsten loads are harder still on contacts, so confirm the contactor's rating for your specific lamp type on the manufacturer spec sheet linked with the product.

They do. Magnetic latching holds the contacts mechanically once set, so a loss of the 120V control supply leaves the A202K3BA in whatever state it was last commanded to. That is an advantage in a parking garage or corridor where you do not want a brownout to kill the lighting, and a drawback if your sequence relies on automatic shutdown at power loss. It also means after a latched contactor is manually operated it stays there until the next control pulse.

The part is B-Line A202K3BA, from the A202 series of NEMA lighting contactors. That specific catalog number is the two-pole, 100A, magnetically latched configuration with a 120V 60 Hz coil. If the unit you are replacing is a different pole count, ampere rating or coil voltage, the catalog number changes, so read the nameplate on the existing contactor rather than ordering by series alone.

NEMA. The A202K3BA is built to NEMA lighting contactor construction, which is what most North American specifications and facility standards call for and what gives the heavier contact mass and longer service life expected in MRO work. If your drawing calls out an IEC-style contactor with a defined utilization category, this is not that product.