Lenze's product range includes frequency inverters, servo drives, geared motors, motors, clutches and brakes. It also features automation solutions with integrated software, visualisation and controls as well as system engineering, coupling technology and services. This is completed by a global service network which can be accessed 24/7 from anywhere in the world. The world is Lenze's market, so you will find us represented in all its major locations. Our largest operational sites are located in Aerzen and Extertal (Germany), Asten (Austria), Shanghai (China) and Uxbridge, Massachusetts (USA).
If you are looking for Lenze Drives, please call us at (800) 894-0412 or email us at firstname.lastname@example.org we will do our best to help you find the Lenze Motors that you are looking for at the most competitive prices possible. If you are searching for Lenze Servo Inverters technical information (data-sheets) please use the Lenze Datasheets OR Product Selection Guide page links. For a list of user manuals or operating instructions available, please use Lenze Technical Guide page link.
What are the differences between spring-operated and permanent magnet brakes? How are they influenced by free-wheeling diode and spark suppressors?
- The spring-operated brake normally opens at approx. 20 V and closes at approx. 3 V (values depend on size and spring type)
- A Permanent Magnet Brake opens at approx. 20 V and closes at approx. 16 V ≥ this may cause the brake to close in case of voltage fluctuations
- Free-wheeling diodes and spark suppressors protect the switching contact in case of switching on the DC side (for 24V brakes)
- If free-wheeling diodes are used, inductive voltage peaks are decreased. This is not the case with spark suppressors ≥ 6 to 10 times of the brake closing time if a free-wheeling diode is used (compared to spark suppressors)
- If permanent magnet brakes are used the immense time difference is not really perceptible (closes at 16 V) - unlike spring-operated brakes, as the voltage decrease to 3 V takes considerably longer.
This means that the closing time of permanent magnet brake and spring-operated brake is different if free-wheeling diodes are used. Therefore, spark suppressors should be preferred together with spring-operated brakes (in the Lenze brakes catalog a spark suppressor for 24 V is defined - one type for all brake sizes).
It is no problem to use the AIF modules EMF2171IB or EMF2175IB for the communication between an operating terminal and the 8200. With both modules you can transfer data via parameter channel or process data channel. In the Project Manager of the HMI Designer you have to connect the AIF modules to the CAN-port as if they were drives (as DEVICE_CAN_SLAVE or DEVICE_CAN_MASTER). In the HMI Designer Project there is no difference between connecting the HMI CAN-port to a FIF module, an AIF module or an Onboard port of a drive.
Can, if frequency inverters (e. g. 8200 vector or 8400) are applied in DC-bus operation, several internal brake choppers be used in parallel in order to reduce surplus regenerative energy?
No. In a DC-bus operation with several drives only one internal brake chopper can be used to reduce regenerative energy, since - due to the hardware tolerances - it is not ensured that all brake choppers are switched on simultaneously (the internal brake choppers cannot be synchronised). Consequently, all the regenerative energy would be reduced by one of the brake resistors only. The other resistors would not be activated. Further brake resistors would only be activated, when the DC-bus voltage would continue to rise due to an insufficient peak power of a single brake-resistor. This constellation would also lead to an uneven spread of the power loss to the single brake resistors.
If one single internal brake chopper is not sufficient, an external brace chopper should be used, which could also be synchronised with further external brake choppers. This ensures simultaneous activation of all brake choppers. This makes sure that the power loss would be spread evenly to all brake resistors.
Which reasons of process technology justify the operation of a 2-pole asynchronous motor directly at the mains?
In simple applications of material handling technology, e. g. chain or roller conveyors, the geared motor is often operated directly at the mains. For this purpose a 2-pole asynchronous motor is suitable due to its 'smooth' starting characteristics. The higher inductance leads to a starting torque lower than in case of a motor of the same size, but with more poles.
In addition, due to the higher rated speed it outputs a higher performance than motors of the same size with more poles.
Why does the efficiency calculated by the rated data of the motor differ from the value printed in the catalogue?
motor type 080-31 (G-motion): PN = 1.1 kW, IN = 2.8 A, U = 400 V, cos = 0.82, eta = 79 % ≥ Pmech = 1.257 kW With M = 3.7 Nm, nN = 2810 rpm it matches: Pmech = 1.1 kW
The efficiency is calculated from the mechanical power and the electrical data.
Electrical machines have wide manufacturing tolerances and operating conditions. Each parameter measured under worst case conditions (for the current and the power factor) defines the rated data. These values do not appear all together, e. g. the current is measured at the lower voltage tolerance limit (2.8 A). This value is higher than under rated conditions.
The catalogue value for the efficiency is measured at the defined rated voltage (U = 400 V). For the above example with this voltage an efficiency of eta = 0.79 is measured.
Is it possible to operate two motors parallel at a 9300 Servo, and which motor parameters are to be entered?
The operation of two asynchronous motors at one servo controller is possible, if the corresponding selection and the following advices are considered:
- Only identical motors can be used
- They must be coupled shrunk to each other.
- Both motors connected parallel are detected by the Drive Controller as a summated motor.
- Only one feedback system is to be connected to the drive controller.
- The parallel operation of synchronous motors is not possible.
- Only one KTY temperature sensor is to be connected to the drive controller.
- For the second motor a second thermal monitoring is eventually to be installed (PTY, thermal contact).
Residual current protective devices (RCD): What do you have to observe when using RCDs in connection with drive controllers?
A residual-current device (RCD), similar to a Residual Current Circuit Breaker (RCCB), is an electrical wiring device that disconnects a circuit whenever it detects that the electric current is not balanced between the energized conductor and the return neutral conductor.
During controller operation, there always occur leakage currents of different frequencies. In connection with residual current protective devices (RCDs), these leakage currents are detected as residual currents and may lead to a tripping of the RCD.
The Modular Structure of the brake enables flexible use with single or dual rotor. The new high-performance braking system has been developed for use in crane systems, port facilities, ship winches, hoists, and belt conveyors. A new manual release has been designed specifically for this brake meeting the high requirements of the enclosure rating. This brake is only to be actuated with a bridge half-wave rectifier (included in the scope of supply).
The Main Characteristic of the magnetic particle clutch is the possibility to smoothly change the torque depending on the coil current. In order to produce a torque, the clutch has to be excited by DC voltage. A magnetic field is produced. To transmit the torque from the external to the internal rotor made of special alloy and highly abrasion-resistant iron particles are inserted into the gap between the rotors.