SEW BrakesSEW Brakes

1 SEW BrakesSEW BrakesService and MaintenanceSEW-EURODRIVE Driving the worldProduct Training2 Objectives Upon completion of this session, you will be able to do the following:-Identify the components of an SEW brakemotor-Identify the components of an SEW brakemotor- Explain the operation of the SEW brakemotor- Apply basic troubleshooting proceduresSEW-EURODRIVE Driving the worldProduct Training3 brake Purpose To Stop Motion- The brake engages when power is removed from the motor- The brake applies force to an object in motion until friction either slows or stops the Motor slows and finally stops To Prevent MotionTo Prevent Motion- brake engages after motor has come to complete stopto complete stop- brake merely holds motor to prevent Driving the Training4 brake Features SEW features: Fail-safe operation Rectifier for conversion of AC into DC current DC controlled brake coilWithout a fail-safe brake , hldhwhat would happen to machinery in the event of a power loss?

2 Wh t bt thdt?SEW-EURODRIVE Driving the worldWhat about the product?Product Training5 brake Operation Coil functions like an electromagnet when energizedBrake CoilSEW-EURODRIVE Driving the worldProduct Training6 brake OperationDe-energizedEnergizedWhen the coil is de-energized, the springs apply force to the When the coil is energized, its magnetic field pulls the platepg ppystationary plate. This force presses against the brake disc to create friction. magnetic field pulls the plate towards the coil. The magnetic force compresses the springs. SEW-EURODRIVE Driving the worldFriction stops the motor and/or prevents it from motor can now rotate freely. VIDEOP roduct Training7 brake Operation Coil:- The brake coil actually consists of two separate parts: an Accelerator coil (BS)and aFractionalholding coil (TS).Accelerator coil (BS)and a Fractionalholding coil (TS).- An SEW brake rectifier controls both Driving the worldBrake CoilProduct Training8 brake Operation Step 1- Initially, the rectifier energizes the Accelerator (BS) coil very quickly, due to its low , due to its low resistance = High CurrentHigh Current = Strong ElectromagnetismHigh Current = Strong ElectromagnetismStrong Electromagnetism = Fast ReactionRectifierMotorBrakeRectifierInpu t PowerSEW-EURODRIVE Driving the worldProduct Training9 brake Operation Step 2- After 120 ms, the rectifier energizes both coils.

3 Combined coils have a higher resistance, allowing the coils to de-energize fasterhave a higher resistance, allowing the coils to deenergize faster when power is resistance = Low CurrentHigh resistance = Low CurrentLow Current = Weak ElectromagnetismWeak Electromagnetism = Quick Coil CollapseRectifierMotorBrakeRectifierInpu t PowerSEW-EURODRIVE Driving the worldProduct Training10 brake OperationMotorBrakeRectifier Step 1 Input Power Step 2 120msSep0sSEW-EURODRIVE Driving the worldProduct Training11 brake Operation Starting1. The rectifier energizes the brake The brake coil attracts the stationary disc, removing pressure between stationary disc and brake Motor rotates freely. Stopping Stopping1. Rectifier de-energizes the brake springs create pressure between stationary disc and brake Driving the world3. Friction stops motor and prevents it from Training12 brake ComponentsBrake Disc (rotates)SpringAir GapBrake End ShieldBrake Carrier () brake Coil(rotates)Coil BodyBrake Rotor Shaft (rotates)SEW-EURODRIVE Driving the worldDampening Plate (BMGonly)Stationary Disc (moves)Product Training13 brake ComponentsDiscDiscCoilSpringCoilSEW-EURO DRIVE Driving the worldSpringProduct Training14 brake Components Rectifiers and relays that mount in Motor Conduit BoxSEW-EURODRIVE Driving the worldProduct Training15 brake Components Rectifiers that mount in Control PanelSEW-EURODRIVE Driving the worldProduct Training16 brake Components Typical wiring diagramSEW-EURODRIVE Driving the worldProduct Training17 Troubleshooting Troubleshooting an SEW brakeSEW-EURODRIVE Driving the worldProduct Training18 Troubleshooting Always follow the proper lockout/tagout procedures.

4 Use the proper safety equipment at all timesSEW-EURODRIVE Driving the worldProduct Training19 Troubleshooting Resources needed-Nameplate data from motorNameplate data from motor- Brakemotor operating instructions- Motor/Brakemotor parts list- Digital multi-meterSEW-EURODRIVE Driving the worldProduct Training20 Troubleshooting Possible FaultsRtifi idd-Rectifier is Rectifier is wired AC brake voltage is incorrect or not coil is damaged or malfunctioning- brake coil is damaged or brake is mechanically Air gap is outside of disc is worn or Driving the world- brake disc is worn or Training21 Troubleshooting brake rectifier is damaged- Incorrect voltage or wiring of the rectifier causes internal or ggexternal damageRectifier received incorrect voltageComponents are damagedSEW-EURODRIVE Driving the worldProduct Training22 Troubleshooting Rectifier is wired to nameplate for correct type of-Refer to nameplate for correct type of connection (Conn Dia)

5 Refer to the operating instructions for wiring-Refer to the operating instructions for wiring diagramsSEW-EURODRIVE Driving the worldProduct Training23 Troubleshooting AC brake voltage is incorrect or not appliedRefer to nameplate for correct brake voltage-Refer to nameplate for correct brake voltage460 ACAC Voltage that should be applied to the brake rectifierSEW-EURODRIVE Driving the worldppProduct Training24 Troubleshooting Check voltage at brake contactor- If rectifier power does not come from motor terminals, measure p,the voltage at the brake contactor Check the activation of the brake contactorVerify that the brake contactor functions properly and changes-Verify that the brake contactor functions properly and changes position when energizedSEW-EURODRIVE Driving the worldProduct Training25 Troubleshooting brake coil is damaged or malfunctioning-Wrong voltage applied to brake coil causes internal and ggppexternal damageCoil received SEW-EURODRIVE Driving the worldCoece edwrong voltageProduct Training26 Troubleshooting Obtain normal coil resistancesLook up the correct values in the SEW Brakemotor Operating Driving the worldProduct Training27 Troubleshooting Measure the actual resistances of accelerator coil and fractional coil13-14 (accelerator coil)1415 (fractional coil)15-blue14-white w/ blue stripe14-15 (fractional coil)13-15 (total coil)

6 13-red15-blueAccelerator coil winding resistance = of winding resistanceggFractional coil winding resistance= of winding resistanceTotal coil winding resistance= sum of accelerator and holding coil resistanceSEW-EURODRIVE Driving the worldProduct Training28 Troubleshooting brake is mechanically lockedVerify the free play on the release-Verify the free play on the release arm. Loosen the locking nuts as needed to achieve mm gap (S Dimension)gap. (S Dimension)Caution!There must always be clearanceThere must always be clearance on the : The brake release mechanism is notused to change the brake s torque settingSEW-EURODRIVE Driving the worldthe brake s torque setting. Product Training29 Troubleshooting Air gap is outside of tolerance- Insufficient air gap between the dampening plate (BMG Brakes ) gppgp()and the brake coil. (For BM Brakes , there is no dampening plate, so air gap lies between stationary disc and brake coil).

7 Air-gapSEW-EURODRIVE Driving the worldProduct Training30 Troubleshooting Obtain correct value for air up the correct values in the SEW Brakemotor Operating up the correct values in the SEW Brakemotor Operating Driving the worldProduct Training31 Troubleshooting Adjust the brake Air Gap (Method 1) feeler gauge between dampening plate and coil (BMG) or between stationary plate and coil (BM). (3) hex nuts until there is minimal air gap (clearance) equally around the discAttention:When using a feeler gauge BMG b kon a BMG brake , measure from a dimple on the dampening plate!SEW-EURODRIVE Driving the worldProduct Training32 Troubleshooting Adjust the brake Air Gap (Alternate Method 2)1 Tighten the three adjustment nuts equally to establish zero air the three adjustment nuts equally to establish zero air Loosen the adjustment nuts according to the figures SizeDegree of RotationApproximate Rotation AmountBM(G)05, BM(G)1160 7/16 TurnBM(G)2, BM4135 3/8 TurnBM(G)8 180 1/2 TurnBM15, BM30, BM31145 2/5 TurnBM32, BM62135 3/8 TurnBMG61, BMG122145 2/5 TurnNote:Chart is based on the middle air gap tolerance.

8 However all SEW Brakes fall within the air gap toleranceSEW-EURODRIVE Driving the worldHowever, all SEW Brakes fall within the air gap tolerance range if the degree of rotation is Training33 Troubleshooting brake disc is worn or damaged- Sliding friction causes carbon-based brake disc to wearg- High cycle rates require more frequent disc replacement- Overheating can cause stationary disc to warpCarbon composite materialSEW-EURODRIVE Driving the worldProduct Training34 Troubleshooting Check thickness of brake the brake disc with lit d tithtlcalipers to determine the actual disc the disc is below tolerance, litreplace the disc is acceptable, reinstall it according to the parts list and operating instructionsSEW-EURODRIVE Driving the worldoperating Training35 Review What are the components of an SEW brake ? How does an SEW brake function?SHOW ME How does an SEW brake function?SHOW ME What possible faults could occur when an SEW brake does not operate properly?

9 SHOW MESEW-EURODRIVE Driving the worldProduct Training36 brake Operation Starting1. The rectifier energizes the brake The brake coil attracts the stationary disc, removing pressure between stationary disc and brake Motor rotates freely. Stopping Stopping1. Rectifier de-energizes the brake springs create pressure between stationary disc and brake Driving the world3. Friction stops motor and prevents it from Training37 Review What are the components of an SEW brake ? How does an SEW brake function?SHOW ME How does an SEW brake function?SHOW ME What possible faults could occur when an SEW brake does not operate properly?SHOW MESEW-EURODRIVE Driving the worldProduct Training38 brake ComponentsBrake Disc (rotates)SpringAir GapBrake End ShieldBrake Carrier () brake Coil(rotates)Coil BodyBrake Rotor Shaft (rotates)SEW-EURODRIVE Driving the worldDampening Plate (BMGonly)Stationary Disc (moves)Product Training39 Review What are the components of an SEW brake ?

10 How does an SEW brake function?SHOW ME How does an SEW brake function?SHOW ME What possible faults could occur when an SEW brake does not operate properly?SHOW MESEW-EURODRIVE Driving the worldProduct Training40 Troubleshooting Possible FaultsRtifi idd-Rectifier is Rectifier is wired AC brake voltage is incorrect or not coil is damaged or malfunctioning- brake coil is damaged or brake is mechanically Air gap is outside of disc is worn or damagedSEW-EURODRIVE Driving the world- brake disc is worn or damaged.