Configuring SINAMICS V20 Motor Brake Control: P1215 Guide

Overview

The SINAMICS V20 (catalog family 6SL3210-5...) includes a built-in holding brake management function that energizes and releases an electromagnetic motor holding brake through one of the drive's discrete outputs. This function closes the brake before the drive removes excitation from the motor and opens the brake only after the drive has built sufficient torque. For vertical loads, horizontal load-holding applications, and machines that require a controlled stop (cranes, hoists, conveyors, gates, machine-tool spindles), this closed-loop sequencing prevents the load from drifting during the OFF ramp.

The V20's motor run output (r0052 bit 1 / 52.1) is unsuitable for brake control on its own because it transitions as soon as the drive begins the down-ramp, before the mechanical brake can engage. Instead, the drive exposes a dedicated brake released status bit (r0052 bit 12 / 52.12) that remains true while the drive holds the brake open and drops only after the brake has had time to mechanically apply. Wiring this status to DO1 (transistor) or DO2 (relay) and enabling parameter P1215 gives a deterministic, parameter-driven brake sequence with no PLC ladder logic required.

This article documents parameter assignment, signal mapping, wiring, timing values, and commissioning checks for the SINAMICS V20 holding brake function. It also covers the application considerations discussed in field practice: distinguishing normally-closed (N.C.) vs. normally-open (N.O.) brakes, choosing DO1 vs. DO2 for the contactor coil, and validating the sequence with Status word 1 (r0052).

Prerequisites

• Drive: SINAMICS V20, any firmware release (function available from initial release through current FW 6.x). Refer to the SINAMICS V20 Operating Instructions for the parameter list specific to your FW.
• Motor: Three-phase induction motor with a separately-excited electromagnetic holding brake (24 V DC or 230 V AC coil, depending on the variant).
• Brake type: Either N.C. (normally closed / spring-apply / fail-safe) or N.O. (normally open). The V20's internal logic assumes a fail-safe brake (current to release, spring to apply). Verify your motor's brake catalog number.
• Power wiring: Motor U/V/W connected to the drive; protective earth (PE) on both drive and motor; brake rectifier (if AC brake coil) fed from a separate supply.
• Control wiring: Strip wire of 0.5-1.5 mm² for the digital output terminal block on the V20 control board.
• Commissioning tool: Either the V20's IOP (Intelligent Operator Panel) or the BOP (Basic Operator Panel) on the drive front, or the SINAMICS V20 Smart Access web interface module (catalog 6SL3255-0VA00-4BA0) for parameterization over Wi-Fi.
• Safety review: For any lifting or lowering load (host systems per EN 60204-1), evaluate the drive's safe stop functions. The V20 does not provide STO/SS1 natively; an external safety relay is mandatory for personnel protection.

Brake Control Parameters (P1215, P1216, P1217)

The V20's holding brake function is enabled and configured by three parameters. All three live in the Motor / brake parameter group.

When P1215 = 1 or 2, the drive uses the status bit r0052 bit 12 (designated 52.12) as the logical "brake open" signal. Bits 0-15 of r0052 form the drive's first status word, which the V20 documentation references using the 52.xx shorthand. 52.12 is true only during the window when the drive considers the brake released and is actively driving torque into the motor.

Digital Output Signal Mapping (P0731, P0732)

The brake released status (52.12) must be wired to a physical output. The V20 has two discrete outputs on the control terminal strip:

To map the brake signal to the output, set the signal source parameter to 52.12. The source uses a value format of 52.xx where xx is the bit number (decimal) within status word 1 (r0052):

• P0731 = 52.12 — DO1 transistor follows the brake released bit.
• P0732 = 52.12 — DO2 relay follows the brake released bit.

If you are reading an older manual or third-party forum post, the value 52.C may appear. That notation is the hexadecimal form of bit 12 (0xC = 12 decimal). Both forms drive the same logic in the V20 firmware.

Wiring the Brake Contactor

Option A — Direct 24 V DC brake coil on DO1 (transistor)

For low-current 24 V DC brake coils (typical industrial disk-brake motors draw 0.5-1.0 A), the V20's DO1 transistor cannot drive the coil directly because it is limited to 100 mA. Use an interposing relay or DC contactor rated for the brake current:

Option B — AC brake contactor on DO2 (relay)

For a 230 V AC contactor coil or a motor-integrated brake rectifier fed from AC mains, use DO2's relay contact:

• Drive terminal 5 = common (COM of relay).
• Drive terminal 6 = normally-closed (opens when r0052.12 = 1).
• Drive terminal 7 = normally-open (closes when r0052.12 = 1).

Wire L1 to terminal 5, the contactor A1 to terminal 7, and A2 to N. When the drive releases the brake, the relay closes and the contactor (and brake) energize.

Step-by-Step Commissioning

1. Power up the drive. Apply 400/230 V (model dependent) to the line side. Confirm the drive runs the basic operator panel without fault (panel shows ready).
2. Run quick commissioning. Set P0100 = 1 (Europe, kW), P0205 = 1 (motor data from nameplate), enter P0304-P0311 from the motor plate. Run P1900 = 2 (motor identification / rotating autotune) with the motor uncoupled from the load if possible, or with the brake held by the spring (current applied to the motor but brake engaged).
3. Navigate to P1215. Set P1215 = 1 for motor-integrated brake, or P1215 = 2 if an external contactor interposes between the drive output and the brake coil.
4. Set P1216. Consult the brake manufacturer's datasheet. For typical spring-set 24 V DC disc brakes, 0.15-0.30 s is appropriate. If uncertain, set P1216 = 0.20 as a safe starting value.
5. Set P1217. Same source — brake closing time. Typical values 0.10-0.50 s. Use P1217 = 0.20 as a starting value.
6. Map the signal. For relay output (recommended for AC coils), set P0732 = 52.12. For transistor output (with interposing relay), set P0731 = 52.12.
7. Verify DO logic inversion. Some brake designs use N.C. logic (spring-closed, current-released). The V20 outputs are not inverted by default; 52.12 high = brake released. If the coil should be de-energized to release (rare), invert using the bitwise inversion in r0052.12 mapping (P0732 = 152.12 with the invert bit 13 set; refer to the operating instructions list).
8. Lock access. Set P0003 = 3 (Expert), then P0004 = filter on motor/brake if desired, then P0010 = 0 to leave commissioning. Set P0011 = 1 to lock parameters so a field operator cannot overwrite them on the BOP.
9. Test sequence manually. Issue an ON command via terminal DI1 (or via the BOP run key in JOG). The brake should release after the motor has been magnetized for P1216 seconds. Issue OFF. The brake should engage, then the drive should ramp down and de-energize after P1217 seconds.

Timing Sequence (SVG)

The sequence is: ON command rises, drive magnetizes the motor (ramp from 0 to setpoint begins internally), after P1216 seconds the brake status bit (52.12) goes true, the brake physically opens, and the motor ramps to speed. On OFF, the drive ramps down motor speed, after reaching near-zero torque the brake status bit drops, the brake engages, and after P1217 seconds the drive de-energizes.

PLC Integration Considerations

The V20's internal brake logic is sufficient to sequence the brake without any external controller. However, in systems where a PLC already monitors drive state, you can still supervise the sequence from the PLC:

• Read the brake status bit via the V20's USS (RS485) interface using parameter r0052, or via MODBUS register 0x2102 / status word. See the V20 Operating Instructions for the Modbus map.
• If you prefer a hard-wired feedback to the PLC, wire the DO1 (P0731 = 52.12) to a PLC fast input and use it to supervise the sequence and detect stuck brake conditions.
• If the V20 is connected to a higher-level controller (e.g., a SIMATIC S7-1200 over Profinet/Profibus using a SINAMICS V20 PN variant 6SL3210-5BE27-5UV0 or similar), expose P1215/P1216/P1217 via the GSDML and supervise from the PLC program.

For multi-drive systems, the V20's internal logic also supports a simple PLC function (P2020 group, often called the V20 Auto-Routines) for sequencing multiple drives without an external PLC.

Safety Considerations

For lifting/hoisting (host) applications specifically:

• Select a fail-safe spring-set brake; never use a N.O. brake as the sole holding means.
• Size the brake torque equal to or greater than the motor's full-load torque at the worst-case load (typically 1.25-2.0 × rated motor torque for a single-brake hoist).
• Verify that the brake status bit (52.12) drops on every OFF command, including emergency stop, drive fault, and mains loss. If mains is lost, the brake will engage naturally because the contactor de-energizes — ensure your wiring supports that.
• Do not rely on the motor's regenerative braking to hold the load. The V20's down-ramp will brake the load, but any speed setpoint overshoot or unstable load will drop before the brake applies.
• For a vertical hoist, set P1216 to the brake manufacturer's maximum opening time, not the typical. Slow brake = load drops further.
• Verify the brake is rated for the inertia and thermal load. Cycle duty > 100 cycles/hr requires a brake heat calculation.

Verification Procedure

1. Inspect wiring. With the drive de-energized and locked out, verify continuity from drive terminal 7 (DO2 NO) to contactor A1, A2 to N, brake contactor output to brake rectifier input (if used), and PE bonding.
2. Check signal at idle. Apply control power only (no main power). On the BOP, navigate to r0052 and read bit 12. It should read 0. Measure voltage at terminals 5-7: should read mains voltage (relay open).
3. Check signal on command. Apply main power. Issue ON via terminal DI1. The brake should release after P1216. Verify r0052 bit 12 reads 1 and the relay closes. Measure voltage at 5-7: should drop to <1 V (relay closed).
4. Check brake release current. Use a clamp meter on the brake coil lead. Confirm the current matches the brake nameplate (typically 0.5-2 A at 24 V DC, or 0.1-0.5 A at 230 V AC).
5. Check off sequence. Issue OFF. The motor should decelerate per the ramp (P1121), brake should engage, drive should de-energize after P1217.
6. Check fault behavior. Force an overcurrent fault (F0001) by commanding an aggressive accel into a locked load. The drive should remove excitation; the brake should engage because DO2 de-energizes. Verify load does not drop.
7. Long-run thermal check. Run 50 cycles with the load and measure brake coil temperature. Should stay below the rectifier/insulation class (typically class F = 155 °C).

Troubleshooting Matrix

Alternate Configuration — External Brake on Drive Output

If the brake coil is fed from the same mains as the drive (i.e., it cannot tolerate DC or low-voltage operation while the drive is at DC injection state), or if you want the drive's output contactor K2 to be the brake's main contactor rather than a separate relay, set P1215 = 2 and drive the contactor via DO2 directly as shown in the wiring section above. The behavior of r0052 bit 12 is identical for P1215 = 1 and P1215 = 2.

Field-Proven Tips

• Use a separate brake on status feedback to the PLC. Tie the DO1 (P0731 = 52.12) into a fast digital input on the PLC and verify the bit transitions at every run command. A stuck brake (r0052.12 true while contactor is de-energized) indicates a contactor coil failure.
• When commissioning a hoist for the first time, set P1216 = 0.50 s and P1217 = 0.50 s as conservative starting values. Optimize downward after observing a no-load test.
• If using a V20 with FW 4.x or earlier, confirm the parameter is still 52.12 (not 52.C as sometimes printed in older literature). The firmware accepts either format.
• For multi-segment machines with multiple V20s, set the V20 to slave mode on the internal PLC (P2014 group) and use one drive as the sequencer.

FAQ