Lovato 11BGR0901A048 9A Reversing Contactor Assembly

A compact reversing contactor assembly for motor switching

The 11BGR0901A048 is a reversing contactor assembly from the Lovato Electric BGR09 series. Its AC-3 operating current is 9 A, equal to 4 kW at 400 V and 2.2 kW at 230 V for a standard squirrel-cage motor. The coil is rated 48 V AC (read from the order-code suffix).

Technical specifications

Selecting by duty category

For reversing duty the contactors must be selected for the AC-3 current (9 A here) and also for the lower AC-4 figure if the motor is plugged or jogged frequently; the datasheet gives AC-3 powers of 2.2 kW at 230 V, 4 kW at 400 V and 5 kW at 690 V.

Order-code reading, derived from the catalogue entry: 11BGR identifies the reversing assembly, 0901 the size and auxiliary arrangement, and the suffix A048 a 48 V AC coil. Confirm the coil voltage against your control supply.

Applications and mounting

A reversing contactor assembly is two contactors of the BG range delivered as a pair, so the motor can be run in either direction by closing one contactor or the other. The catalogue entry for this code specifies an external interlock with power and auxiliary wiring, which means the interlock between the two contactors is made with the supplied wiring and must not be omitted: closing both at once would short two phases.

Typical applications are small reversing drives such as gate and door operators, hoists, positioners and conveyors that must run forward and backward. The assembly has no built-in overload protection, so a thermal or electronic overload relay or a motor protection circuit breaker is wired upstream, and short-circuit protection is also needed.

The weight of the pre-wired assembly is 394 g and the terminals are clamp-screw type, as the datasheet lists. A built-in auxiliary contact set of 0 NO and 1 NC is quoted for the contactors, which helps with control-circuit interlocking and status feedback.

Installing the BGR09 reversing assembly

Mount the assembly in a closed enclosure on a rigid surface, in the orientation permitted by the Lovato documentation, and leave enough room around it for the power and control cables to be terminated without strain. Tighten the clamp-screw terminals to the torque given by the manufacturer and check them again after the first period of operation, since loose power connections are a common cause of heating. Make sure the control supply that feeds the coils matches the 48 V AC rating before power is applied; a wrong coil voltage can prevent the contactors from closing or damage the coils.

Commissioning a reversing motor circuit

Before the motor is connected, test the control circuit on its own: confirm that the forward and reverse commands each close only the intended contactor and that the interlock prevents both from closing together. Then connect the motor and check that the forward command really turns the driven machine in the forward direction, correcting the phase sequence if needed. Where the machine reverses directly from running, consider a short time delay in the control logic so that the motor slows down before the opposite contactor closes, which reduces mechanical shock and contact wear. Set the overload protection to the motor current and test that a trip opens the control circuit.

Inspection during maintenance

During planned stops, isolate the circuit, look for discolouration on terminals and wiring, check that the assembly operates freely and that the interlock wiring is intact, and listen for humming from the coils when energised, which can indicate a low control voltage or dirt. Replace the assembly if the contacts show signs of heavy wear, rather than adjusting it.

Operating environment in Oman and GCC panels

The AC-3 ratings on this page are given for temperatures up to 55 °C, and the air inside a motor control panel in an unshaded location in Oman or other Gulf countries can reach that level in summer. Install panels in shaded or ventilated areas, keep internal heat sources such as transformers away from the contactors, and allow for the panel temperature when choosing the contactor size for heavily loaded motors. Fine dust can build up on contactors and terminals, so keep enclosures closed and cable entries sealed, and clean the inside of the panel during maintenance. In humid coastal areas, check terminals for corrosion and watch for condensation when panels cool down at night. Gates, door operators and outdoor conveyors that start and reverse many times a day see the most stress, so give these circuits a shorter inspection interval than motors that run continuously in one direction, and keep a record of replacements to judge whether the selected size suits the real duty.

Documents and quotation

Attached is the English datasheet that Lovato Electric’s online catalogue generates for 11BGR0901A048; the specification table above reproduces its values. Please confirm the motor current, coil voltage, the number and type of auxiliary contacts and the utilisation category of your load before you order, and note that the manufacturer may revise datasheet values. More products of this type are under contactors & overload relays. Use the quotation form with the code 11BGR0901A048 and your quantity; availability is confirmed by Seven Star LLC, an independent supplier in Muscat.