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Entry type: FAQ Entry ID: 23485778, Entry date: 04/04/2016

MICROMASTER 4 (MM440), SINAMICS G120 PM240: Connecting cable used to connect-up the braking resistor

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The braking resistor enables loads with a large moment of inertia to be braked quickly.

Which connecting cable is used to connect-up the braking resistor?

The connecting of the brake resistor changes by different frame sizes

Frame sizes A- C
To mount the brake resistor onto a MICROMASTER 440 or SINAMICS G120:

  • for frame sizes A and B a 3 x 1.5 mm², 0.55m long silicon cable is used.
  • for frame size C, a 3 x 1.5 mm², 0.91m long cable is used.
  • The cable is shielded designed for a temperature of 200°C and a voltage of 1000V, and is UL listed (UL-file E69837).
    Frame sizes A and B use cable lugs to connect the cable.
    Frame size C has conductor end sleeves (but not the protective conductor).

In order that the braking resistor with cable lugs can be connected to frame sizes A and B, the cover must be removed in order to access the connecting terminals. Additional information on connections with cable lugs is provided in the Assembly Manual, Power Module PM240 (Entry-ID: 109738501). A simpler solution involves replacing the cable lugs by conductor end sleeves.

Frame sizes D- F 
For this frame sizes there is no cable provided on the system side.
We recommend the following for frame sizes D - F:

  • Frame size D: Cross-section 6 mm², shielded, cable lug, an M6 terminal is provided.
  • Frame size E: Cross-section 16 mm², shielded, cable lug, an M6 terminal is provided.
  • Frame size F: Cross-section 35 mm², shielded, cable lug, an M6 terminal is provided.

Frame sizes FX and GX
Frame size FX & GX do not have an integrated braking chopper. Braking operation can only be implemented using an external braking module.

FAQ: "MICROMASTER 440, FX and GX with a MASTERDRIVES Braking Module" Entry-ID: 22093967 

Further information

  • All of the resistors are equipped with temperature monitoring (UL-file E43273). Non-shielded 0.5 – 2.5 mm² cables can be connected.
  • Information regarding the assembly and to select and dimension the resistor brake is provided in the Operator Instructions of the inverter.
    • MM4: Operating Instructions under "Functions", "Dynamic braking" Beitrags-ID: 24294529
    • G120: Function Manual under "Dynamic braking" Beitrags-ID: 52614597
  • Dimensions are provided in the Catalog  (SINAMICS G120, MICROMASTER 440).
    • The chopper integrated in the drive inverter (up to frame size F) is designed for the rated drive inverter current.
    • The chopper control integrated in the drive inverter is designed for the braking resistor value assigned in the Catalog.
    • The assigned braking resistor is designed for a 5% load duty cycle.
  • This FAQ applies only to the SINAMICS G120/G120D Power Module PM240/PM240-2 and MICROMASTER 4 inverters.