ElectricalTroubleshooting GuideIRB6400 M94APage 8 - 3Brake Circuitry8.8. Brake CircuitryBrake Circuitry8.1 OverviewThe IRB 6400 robot has an axis brake for each axismotor (1-6). The brake is part of the motor and can notbe replaced separately from the motor. The brake isonly a holding brake used to hold the robot in positionwhen the motors are off. When the brake is de-energized,heavy duty springs inside the brake hold metal platesagainst brake material holding the motor in position.The brakes are released by applying 24 VDC to the coilof the brake. The robot motors can override the brakesfor a while until the motor overheats due to the extraload caused by the brake.If an axis brake is slipping it will only cause a problemwhen the motors are off because the axis will drift to itshard stop. The normal cause of a brake slipping is oilgetting into the brake pads due to a seal that has failed.To test a brake for proper operation turn on the maindisconnect and press the manual release button on therobot to see if the brake releases. If further testing isrequired, check the wiring to the brake and the brakecoil resistance. The normal brake resistance should beapproximately 15-30 ohms.USE EXTREME CAUTION WHEN MANUALLYRELEASING BRAKES. ROBOT MAY FALL OR RISEUNEXPECTEDLY CAUSING PERSONAL INJURYOR TOOLING DAMAGE!!In this chapter we will trace the circuits used for thebrake release circuits. There will be two sections, onefor Manual Brake Release circuits and one for MotorsON Brake Release circuits.Sheet 104-110..............Fig. 8-3 ............Fig. 8-5 ............Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
