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Entry type: Application example Entry ID: 109477754, Entry date: 08/23/2017

SINAMICS Brake Test with SINUMERIK 840D sl

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Axes and mechanical systems can drop due to gravity when the drives are switched off. Dangerous motion can result for vertical axes or for rotary axes or spindles with an asymmetrical weight distribution. For this reason, a drive must also be safely held in position when switched off (no current condition). This is usually implemented using a holding brake. The reliability of this holding brake is an essential part of the protection function against falling vertical axes.
The "Safe Brake Control" function (SBC) is used to control holding brakes that function according to the closed-circuit principle (e.g. motor holding brake). The brake is controlled via a two-channel output of the SINAMICS Motor Module. SBC (if configured) is always triggered together with STO.
The brake test checks whether the expected holding torque is still available. The drive moves against the closed brake and applies the test torque – there should be no axis movement if the test is successful. However, if an axis movement is detected, it must be assumed that the brake holding torque is no longer sufficient to hold the axis in position. In this case, the relevant axis must be traversed to a safe position and the brake checked and repaired, if required.

  109477754_SINAMICS_Brake_test_V6_en.pdf (2,1 MB)

 Registrierung notwendig  SI_BT_AWL_V3.0.AWL (15,9 KB) 

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