BCC3000 Brake Control System. Safety. Made in Germany.

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1 BCC3000 Brake Control System. Safety. Made in Germany.

2 BCC3000 Brake Control System Safety The BCC3000 system is the ideal solution for the controlled braking of machines and applications. It is especially useful for belt conveyors, where smooth braking is vital to prevent undue belt tensions leading to reduced component life. In addition to protecting the machine from excessive stresses during braking the BCC3000 also offers system monitoring and diagnostics functions. Adjust Pressure (Torque) Proportional valve Algorithm Brake Apply Measure Speed Compare to programmed ramp Features Fully integrated closed loop control system Apply to either low speed or high speed brakes Stopping time constant & independent of load Synchronous braking times achieved for a flight of conveyors Automatic compensation for small variations of friction coefficient Stopping profile selectable can be user set Battery back-up for all control functions Hydraulic accumulator back-up for full control in the event of total power fail Profibus / Profinet connection for control and monitoring functions Back-up soft braking torque control in the event of total system failure The system consists of four main elements: 1. Redundant encoders, to measure speed 2. Electronic unit which gives full system control and monitoring 3. Hydraulic power pack, incorporating the proportional control valve 4. Brake caliper, either low speed or high speed (application dependant)

3 Redundant speed encoder 1. Encoder The shaft speed is measured using an encoder mounted to the shaft that is to be controlled. In the case of a conveyor the driven pulley is usually selected as the control with the brake disc and encoder fitted to this shaft accordingly. Typically fitted onto the low speed, driven pulley, the encoder would have 2048 pulses per revolution. It is recommended that a second encoder is used for safety critical applications such that, in the event of an encoder failure the system will be fully functional throughout, using the second encoder signal. Both encoders should be fitted to the same shaft. Any failure of the encoder is detected by the electronics and a signal sent via Profibus to warn of the condition, not just when the brakes are operated. 2. Electronic Control Unit The electronic control unit is the heart of the BCC3000 unit as it controls all of the logic and operating functions of the braking system. Its primary function is to control the deceleration (stopping time) of the machine or conveyor. The unit is based on a Siemens plc with a graphics interface to view and check program data. During commissioning a speed ramp is entered into the system (See right). The value of the stopping time and the 2 intermediate states (percentage speed/time) can be entered and adjusted until the desired profile is achieved. When the conveyor is commanded to stop (either by a hard-wire or Profibus external command, or both) the speed of the machine is determined from the encoder and this is then compared to the desired speed profile. If the actual speed is high then the pressure to the brake caliper is reduced. This increases the clamping force of the unit thus increasing the braking torque until the desired speed ramp is reached. If the actual speed is too low then the pressure to the caliper is increased, reducing the amount of braking torque, until the desired profile is reached. These adjustments are carried out on a continual basis throughout the stop using a proportional/integral control algorithm to adjust pressure via the proportional valve on the hydraulic unit. Speed ramp (example only) Once the conveyor is at rest then the system removes all hydraulic pressure to set maximum braking torque for parking the machine.

4 Electronic Control Unit (continued) The system is built into a stainless steel cabinet and includes all interface and control relays to be able to operate and monitor the braking system. Features 1. Siemens outdoor plc with additional internal graphics display 2. Motor starter with thermal protection 3. Profibus / Profinet connection to main plant plc 4. Battery back-up to give controlled power available for 30 minutes in the event of external power failure 5. Optional local operation with external e-stop & over-ride 6. All control relays for each valve on the hydraulic power pack 7. Drive amplifier for the proportional valve (pressure) 8. 2 speed inputs with failure warning 9. Central Interface between customer PLC and Brake Monitoring Systems BCC 3000 PLC 3. Hydraulic Power Pack main features >> Motor driven radial piston pump >> In-line filter with clogging indicator, >> Pressure relief valve, pressure switch to control operation >> Proportional valve for a controlled stop >> Dual 3/2 directional valves for soft e-stop (safety feature) >> Hand-pump for manual release (switch to indicate position) >> 2 stage oil level switch >> 2 stage oil temperature switch >> Option to use pressure transducers for monitoring and control >> Can operate up to 4 linked calipers (depending on spacing) >> Pre-wired terminal box (stainless steel)

5 Operation When power is first applied the motor/pump is started to charge the main system accumulator. This accumulator is used in the event of a stop with no power to the pump. Oil discharges through the proportional valve to give full pressure control. Normally the pump will be used to provide control. When the brake is released all parts of the circuit are fully closed with seated low leakage valves. This means that the pump/motor operation does not cycles frequently. All functions of the hydraulic unit are controlled through the electronics. Functional switch positions are added to the Profibus connection. This enables detailed monitoring to assess service and maintainability requirements. 4. Brake Calipers Up to 4 brake calipers can be connected to a single hydraulic power pack and control system if they all brake the same shaft in the machine. These can be on the high speed (gearbox input shaft) or on the low speed (gearbox output shaft). The brakes used on the high speed shaft can based on the standard calipers from PINTSCH BUBENZER that have many years of reliable service in many types of applications. In this case however the standard electro-hydraulic thruster is replaced by a simple low friction hydraulic cylinder. On the low speed side of the machine one or more SF brake calipers from PINTSCH BUBENZER can be used. Such brakes can be fitted with instrumentation that connects via Profibus to the main plant plc using the CMB2 monitoring systems from PINTSCH BU- BENZER. Such systems, together with the monitoring of the hydraulic power pack using the BCC3000 offers complete system feedback on the operational parameter through the service life of the brake system. Hydraulic Power Unit Optional Features In addition to the standard BCC3000 control system PINTSCH BUBENZER are able to modify and design a system to suit particular customer requirements. Such optional extras for previous projects have included: Dual hydraulic circuit 50% brake torque with fast response (<100ms) and based on the well proven SOS safety system developed by PINTSCH BUBENZER and used extensively on dockside cranes. Followed by 50% controlled deceleration Master/Slave configuration for multiple braked drive units on a single conveyor one BCC3000 acts as the Master, sending a secondary control signal to the proportional valve of the slave units Local/Remote operation with e-stop over-ride Remote access/interrogation & programming refer to manufacturer to discuss detailed requirements

6 PINTSCH BUBENZER GmbH Friedrichshuettenstr. 1 D Kirchen-Wehbach Phone +49 (0) 27 41/ Huenxer Str. 149 D Dinslaken Phone +49 (0) 20 64/ PINTSCH BUBENZER A Schaltbau Company