Rotary Positioning Motion Controller BES-516-604, Typical Applications Balluff Zero Speed Controller on a Grinding Machine The Zero-Speed Controller monitors the rotation of the grinding wheel, and shuts the machine down immediately in case the drive shaft breaks. Balluff Motion Controller on an Automatic Lathe Automatic lathes demand a high degree of precision due to their complex and rapid switching sequences. It is especially important to monitor the speed range of the drive spindle for desired vs. actual rpm, and to store the maximum permitted rotational speed in memory as an error. Solving such problems is what the BALLUFF family of motion control devices is designed to do, whether the application is generic or customer-specific. www.balluff.com 1-800-543-8390 G23 Motion Controller BES-516-604 Design The motion control housing is made of thermoplastic, and can be mounted with screws or on a DIN rail. The unit provides 24 V DC (±20% at max. 20 mA load) supply voltage for the inductive proximity sensor. Function The pulse sequence from the inductive proximity sensor is compared with a preset nominal value, based on the pulse repetition period. This approach eliminates time delays which could occur if mean value calculations were used. As soon as the nominal pulse number is exceeded, relay d1 is energized and the correspond- ing LED comes on. If the actual count falls below the nominal pulse number by a factor greater than the preset hysteresis, relay d1 is blocked (opens), and the LED goes out. Relay d1 also opens if power is lost or the proximity sensor cable is broken. Applications When used in conjunction with an inductive proximity sensor (such as BALLUFF type BES-516-3..), the motion control device digitally monitors the agreement between the actual value and the nominal, preset pulse number. The device has universal application wherever pulse counts can be made. These applications include machine stop control, monitoring of stroke speeds, conveyor belts, and shaft break monitoring. If the motion control device is used to monitor safety functions on a machine, the application must conform to the appropriate industrial safety standards. Using Other Input Devices Other input devices, such as optoelectronic sensors or magnetic field sensors, may be used as long as the minimum pulse duration is >1 ms. If the sensor has its own external power supply, care must be taken to ensure that the minus potential of the sensor is connected to terminal 10 (minus) and the pulse signals to terminal 8 (A). Terminal 9 (plus) is then not connected. Start-up Bridge In order to bridge the difference between the actual and nominal pulse number in the start-up phase of the machine, we also offer units with a start-up bridge. The start-up bridge can be factory set (per customer requirement) or externally set (using potentiometer P 2) from 0.1 to 2 seconds. Other ranges up to max. 30 s are also available. Initiating the start-up bridge must be done with a potential-free external contact. If the start contact is closed, a separate relay (d 2) is energized and opens again after the preset time has elapsed. The bridge relay can be checked for function using an external circuit. G24 1-800-543-8390 www.balluff.com Rotary Positioning Rotary Positioning Motion Controller BES-516-604 Hysteresis Hysteresis is defined as the percentage value of the pulse number which must not be exceeded after the nominal pulse number is reached, so that the device can be turned off again. In this way, any application-induced pulse number variations which occur during running can be picked up. After the nominal pulse number is reached, the actual pulse number must be undershot by the amount of the preset hyster- esis before the device can be turned off. The hysteresis range can be internally set with a trim pot, from 10% to 45%. The usual factory set range is 20% (±10%). In order to change the hysteresis value, the device must be opened; this makes unauthorized access more difficult. Installation Hints Proximity sensor cables should not be routed together with cables from other sources. If there is a possibility of external noise interference (e.g. high voltage peaks), the minus lead (terminal 10 on the device) should be grounded to the machine. Under extreme conditions, shielding may be required. Note: For machine stop monitoring application, relay d 1 is de-energized (opens) when the nominal pulse number is exceeded and the corresponding LED goes out. If the actual pulse count falls short of the nomimal count by more than the preset hysteresis, relay d 1 is energized again (closes) and the LED comes on. Function Check When Setting Up When setting up the motion control device (models CO and CZ as well as DO and DZ), please note the following: 1. Jumper the contact of output relay d 1 (terminals 4/5 or 6/7 if d 1 has positive- opening contact, or 5/6 or 6/7 if d 1 has a changeover contact). 2. Start the machine and run in the desired speed range. 3. Using the scale on potentiometer P 1, adjust the preset nominal pulse number by turning the potentiometer clockwise until the LED goes out. Then turn the potentiometer counter-clockwise until the LED comes on again. To ensure a margin of safety in the case of possible pulse number variations, the potentiom- eter should be turned slightly further in the counter-clockwise direction by an amount which compensates for individual machine characteristics. 4. Remove jumpers from 4/5 - 6/7 or 5/6 - 6/7. Now the device is precisely set for the desired pulse number. By bridging the contacts (point 1 above), the function of the device with respect to the machine control is deactivated or bridged. www.balluff.com 1-800-543-8390 G25 Motion Controller BES-516-604 Technical Data Housing Output d 2 (start-up bridge) Calculating Nominal Gray Thermoplastic 1 relay with 1 changeover contact Pulse Number Enclosure rating IP 50 Contact load 250 VAC/8 A (2000 V A) i = n x z or The min. pulse duration which the Connections 1 relay with positive opening contacts device can accept is 1 ms with a pulse 20 screw terminal for 2 x AWG 12 1 NO and 1 NC Contact load 220 V duty factor of 1:2 connectors AC/5 A Enclosure rating IP 10 (max. 500 V A) Operating Temperature 0°C to +60°C (+32°F to +140°F) Housing Mount Positive Opening Contacts 1. Snap mount for standard 35 mm In a positive opening contact group, Hysteresis DIN rail, or all contacts are in the operating or on Adjustable between 10% and 45%, 2. 2 screws M 4 or M 5 state after a turn-on sequence, and not based on preset nominal value of pulse operating or off state when de- count (±10% tolerance). Supply Voltage energized. If one or more of the 110/220 V AC ±15% 50-60 Hz contacts has a fault, all contacts will Tolerance 42 V AC ±15% 50-60 Hz assume the same condition as the The tolerance of the factory set pulse 24 V DC ±20% - 10% faulty contact, even if another count for models, AO, AZ, BO, BZ, condition existed before the fault. GO, and GZ is ±10%. Output d 1 (motion control) 1 relay with 1 changeover contact Response time LED Contact load 250 V AC/8 A 60 The LED comes on when relay d 1 is (2000 V A) or t= f minus preset hysteresis energized (nominal pulse number is 1 relay with positive opening contacts exceeded), and goes out when relay d 1 NO and 1 NC contact load 220 V Calculating Machine RPM 1 is de-energized. AC/5 A i (max. 500 V A) n= z Input Devices Inductive proximity sensors, prefera- n = machine speed in rpm bly PNP logic (e.g. BALLUFF i = preset pulse number/min. BES-516-3..) with max. 20 mA current (nominal pulse number) draw. z = number of teeth or pulse number per revolution Housing Dimensions G26 1-800-543-8390 www.balluff.com Rotary Positioning Rotary Positioning Motion Controller BES-516-604 Function Diagram of Motion of Controller The power supply converts the external supply voltage from 220/110 V AC to 24 V DC. This secondary voltage is rectified and stabilized. The pulses sent by the inductive proximity sensor pass through an input filter into a mono-flop stage. The nominal pulse number is given as a DC voltage to a sawtooth generator and comparator circuit, which com- pares the nominal value with the actual value (input pulses). The result is stored in the memory which switches relay d 1. The start-up bridge is an adjustable time delay from 0.1 to 2 sec., which switches relay d 2 for the preset time. Typical Circuit for BES-604 with Start-Up Bridge Monitored on Machine Control Side and Open-Delayed Time Relay After pressing the “On” switch, relay d2 of the start-up bridge is energized, contact ZR 1 is closed, and drive protection c 1 is activated. If the nominal pulse number is reached, relay d 1 pulls up. Relay d 2 is blocked. Time relay ZR 1 goes to no current, and contact ZR 1 opens after a delay. Drive protection c 1 remains activated by contacts d 1 (NO) and d 2 (NC). www.balluff.com 1-800-543-8390 G27 Motion Controller BES-516-604-HZ, Signal Timing Diagram Start Phase The start pulse (jumper terminal 15 to terminal 16) energizes relay d 2 after time t1 during the preset start-up delay. The shaft begins to rotate. At the same time, the rotation pulses commence and the internal measuring cycle begins to run. The length of this cycle depends directly on the preset nominal pulse number (small pulse number = long measuring time). Run As soon as the period length T of the rotation pulses reaches the length of the measuring time, if the nominal pulse number is reached the relay d 1 pulls up. The start-up bridge has accomplished its purpose. If properly set, the start-up relay d 2 opens (de-energizes) right after d 1 pulls up (this time is machine- specific). Stop Phase The “Off” command from the controller starts to brake the drive. The number of pulses decreases and their period length T increases. As soon as this length reaches the length of the internal measuring time plus the preset hysteresis, the motion relay is de-energized (opens). Signal Timing Diagram t = ca. 25 ms Internal relays d 1 and d 2 have 1 Consists of an internal constant time positive opening contacts. The motion and the pull-up delay of d 2 (ca. 10 ms controller does not have 2 channels. - 15 ms). For 2-channel control, 2 motion controllers are required. t = 10 ms 2 This represents the time until relay d 1 Pulse relay d 1 assumes the home pulls up after the nominal pulse position after time “t”. number has been reached (plus pull- 60 up delay of d 1 = ca. 10 ms). t= f minus preset hysteresis t = 5 ms plus 5 ms relay release time 3 The time until relay d 1 releases if the nominal pulse number plus hysteresis f = preset pulse number/min. is not reached. Includes the release The time “t” corresponds to the time of d 1 (≤5 ms). reaction time of the device for shaft break monitoring. G28 1-800-543-8390 www.balluff.com Rotary Positioning Rotary Positioning Motion Controller BES-516-604-HZ Design Features error memory for speeds above the max. preset, and dynamic function checking of the proximity sensor. For protection against excessively high rotational speeds on drive motors, a version (type HZ) has been developed which meets specification of the European automobile industry. As soon as a preset rotational speed is exceeded, the power circuit of the drive unit is contact interrupted. In addition, this version recognizes motor overload and signals this to the output circuit. The output relays operate on the rest current principle and have a memory function. The combination of motion controller and sensor function independently of the regulating circuit of the machine. Function The motion controller is operative immediately after power is applied. The pulses sent by an inductive proximity sensor are compared with a defined pulse number stored in the controller (min./max.) and processed accordingly. If the number is either exceeded or not reached, the output circuit is activated and the output relay releases (opens). To test for function, the input signals “Test” and “Start” are activated. The “Test” signal serves as a function control for the output relay and allows the relay to release for 100 ms. The peripheral controller checks the necessary change in condition. The “Start” signal activates the start-up bridge, after which rotation pulses must be present, whereby the sensor is dynamically checked for proper function. Any error recognized by the motion controller is stored and can be cancelled either with the “Reset” button or by interrupting supply voltage. Housing Styles for Balluff Motion and Zero-Speed Controllers www.balluff.com 1-800-543-8390 G29 Motion Controller BES-516-604 Ordering Code for Motion Control and Zero-Speed Controllers BES - 516 - 604 - A Z - 3 Fixed Designation Motion Controllers - Zero-Speed Controllers 604 =Standard Type Versions Motion Controller A = With fixed pulse number no start-up bridge Motion Controller B = with fixed pulse number with fixed start-up bridge Motion Controller C = with adjustable pulse number no start-up bridge Motion Controller D = with adjustable pulse number with adjustable start-up bridge Zero-Speed controller E = with adjustable pulse number with pre-settable start-up bridge and fine range set Zero-Speed Controller G = with fixed pulse number without start-up bridge Motion Controller H = with error memory for exceeding max. permitted rpm with function check of sensor Output O = Relay with changeover contact Z = Relay with positive-opening contacts (1 NO + NC) Supply Voltage 2 = 42 V AC 3 = 110/220 V AC A = 24 V DC G30 1-800-543-8390 www.balluff.com Rotary Positioning