Power Drives - The advantages of Lock EWA

EWA knows no compromises and displays no weaknesses

Lock EWA power drives are a dependable power source for every application. Slowrunning with self-locking worm gear units and integrated limit switches or control unit, they perform their tasks for decades without requiring any maintenance work. As option A60 also for operation at low temperatures.

As a low-cost alternative, there are the HWA manual drives that are of course easy to retrofi t as EWA power drives.

Lock drives can be used for far more than ventilation tasks. Much of what you have to lift and relocate you can make happen using drive units and accessories from Lock.

  • Torque range of 50 –2000 Nm.
  • Speed range of 1–60 rpm.
  • Integrated precision gear limit switch END 20 or integrated LSC 40 control unit.
  • Dimensioning for decades of operational service.
  • Self-locking worm gear units.
  • Electric motors with optimized characteristics for 50 and 60 Hz.
  • Turnkey status for single-phase motors.
  • Optional PAR 06 potentiometer or PAR 10 multiturn-sensor pre-installed on END 20.
  • Optional position sensor, analogue LPR 02 or digital LPR 04 on the LSC 40.
  • Motors and microswitches on the END 20 for 60 Hz are cURus-certified (cURus = UL Recognized Component Mark, valid for the USA and Canada).
EWA 16 (900 - 1500 Nm)

Advantages of Lock drives

  • Standard mounting dimensions.
  • Compact shape.
  • Uniform shaft length.
  • Any installation position.
  • Optional LockLogic®.
  • Zero-maintenance.
  • Selection of shaft types.
  • Extremely quiet operation.
  • A60 for use at low temperatures.
  • Speedlogic frequency inverter.

END 20

END 20 - Precision for EWA

LSC 40

Lock Antriebstechnik // lockdrives - LSC 40 Kontrolleinheit

Position feedback PAR 10

  • Programmable multiturn sensor to provide positional feedback.
  • High resolution for very precise positioning, no jumps or system crashes.
  • No mechanical limit stop and no mechanical wear.
  • Pre-assembled or suitable for retrofitting to END 20 limit switches.
  • „Elektronisches Poti“ austauschbar gegen PAR 06.
  • Number of shaft rotations: 0.1 to 190 can be evaluated.
  • Simple teaching in, using two buttons on the device, with status displayed by LED.
  • Signal output 0 – 10 V analogue or 0 – 5 V.
  • Power supply 16 – 30 V DC, same connection as PAR 06.

Optional: LSC 40.10 control unit

  • Absolute mechatronic limit switch system with integrated additional switches for AC or DC control voltage.
  • Fast and simple setting without power connection, with familiar high level of reliability.


  • “Integrated position sensor” LPR with high resolution.
  • Only one version for all rotational speeds – no additional components.
  • No additional teach-in required.
  • No mechanical limit stop / wear.
  • Outputs with 0-10 V, 4-20 mA and incremental signal.


At Lock you are always offered a large number of types, variant and options so that you can select the optimum solution for your task.

  • Torques and speeds(see table)
  • Shaft ends We 06, We 66, We 19
  • External mounting A60 (option)
  • Special voltages 1~, 3~, DC
  • Mounting types and positions
  • Switching elements END 20, PAR 06, PAR 10
  • Optional control unit LSC 40.10,LPR 02, LPR 04.
  • Color DB 701 platinum gray


Thanks to the broad product portfolioand the modularity of the drives in conjunction with the gear units, systems can be created that optimally move loads in point, line or even area.

Example: A drive with a rack and pinion gear or a cable drum moves point loads.
Example of in-line ventilation: A drive lifts linear loads via shafts and rack and pinion gears.
Example greenhouse beam ventilation: A drive moves large areas via shafts, rack and pinion gears and levers.

Everything you always wanted to know about the EWA 10 - EWA 16 drives!

In all cases, a distinction is made with self-locking between static and dynamic self-locking. Static self-locking only works when stationary and can be cancelled by shaking or by vibration.

This is why our self-locking drive units always have dynamic self-locking (also called autobraking). This occurs whenever an operating gear unit comes to a complete stop automatically, for example after the motor has been switched off. Like all self-locking gear units, our gear units cannot be operated in continuous basis.

Our nominal load details are minimum figures, not maximum figures, unlike the practice of many other manufacturers. That means that if we quote a torque rating of ‚250 Nm‘, that means that the drive unit is capable of delivering this torque rating throughout its entire service life. This explains why our drive units are renowned for having high reserves of power.

On our in-house test benches, we test our units for 1000 operating hours at the nominal load quoted in the catalogue, over the specified engagement period. The drive units are designed for endurance loads depending on utilization level (actual torque levels applied), application, peak loads and engagement cycles.

We do not use standard motors. Instead, we only use motors with optimized characteristics curves, and we optimize these for each version and for every variant. They are designed in such a way that voltage fl uctuations of approx. +/- 5 % can be contended with, even in the 60-Hz range.

Single-phase motors are always wired by ourselves before they leave the factory, and are supplied with a long connection cable. That means that the electric motor is switched off directly by the limit switch. This greatly simplifi es assembly and is less expensive, because there is no need for a reversible contactor control system. A test run can be conducted on location using manual push-button TST 10.

Having said that, single-phase motors must not be over-dimensioned. If they are operated at levels well below their nominal load rating, they are prone to heating up more, and this shortens their engagement period. The internal winding protection contact can be routed externally.

For 60 Hz we have always used special motors. We also always guarantee that the nominal load rating quoted is consistently achievable. This also applies to the other special voltage ratings. All special motors are optimized and tested before they are used on the test bench.

Power drives EWA 10 and EWA 12 can be supplied with 24 V DC motors. A typical feature of DC motors is that current intake rise sharply as torque levels rise.

Natural ventilation systems are often combined with smoke & heat extraction systems. With building-specifi c special constructions, no usability verifi cation can be provided in accordance with DIN EN 121 Part 2.

Here, it is possible to apply for consent in individual cases from the construction authorities. Our drive units have been inspected by the Fraunhofer Institut in respect of ‚usability‘ as defi ned in DIN 18232. Request the Fraunhofer certifi cate when needed.

This option is suitable for use in protected outdoor environments because it has stainless steel output shafts and a special grade of thermally resistant oil for low temperatures. Separate installation conditions apply for use in outdoor environments (see chapter Service/operating instructions).

Optional equipment available for the END 20 limit switch includes our power drives with the LSC 40.10. As standard, this includes the additional limit switch and can be extended to take LPR 02 analogue signals, or can be extended with the LPR 04 to take analogue and digital signals.