Product Description:

The 136G7342 is a digital soft starter manufactured by Danfoss as part of the MCD Soft Starters series. Installed between the line supply and an AC induction motor, it modulates the applied voltage during acceleration and deceleration so mechanical couplings, belts, and gearboxes experience lower dynamic stress. In automated plant lines, this controlled ramp limits peak demand and simplifies downstream protective sizing, making the unit a common component in variable-load conveyors, centrifugal pumps, and other constant-speed three-phase drives. That approach also reduces abrupt torque transfer at startup and helps limit belt slip or coupling shock during routine motor starts.

Electrically, the device is rated for a motor line current of 244 A, so contactors and line-side conductors must be sized accordingly. Control electronics accept a low-level trigger of 24 VAC/VDC, enabling direct connection to PLC relay outputs without interposing converters. An integrated internal bypass closes after the ramp phase, transferring load current through low-loss contacts and minimizing heat dissipation inside the enclosure. Because the starter is specified for three-phase power, its SCR stack conducts on all three lines to maintain balanced phase symmetry. The assembly carries an IP00 rating, so it must be mounted inside a separate panel or enclosure that provides the required protection.

Mechanical layout is supported by the starter’s 216 mm width, allowing it to share standard 600 mm cabinet rails with contactors and fuses. Line and load conductors land on copper busbars, and their clamping screws are tightened to 19 Nm to maintain low-resistance joints during thermal cycling. For network fault coordination, the unit withstands through-fault currents up to 18 kA @ 600 V AC when protected by appropriately rated upstream breakers. This arrangement helps keep power connections orderly within enclosed motor-control panels and supports clear separation between incoming and outgoing conductors.