Glossary SEW-EURODRIVE Canada



ABMA - American Bearing Manufacturers Association

American Bearing Manufacturers Association

ABMA's mission is to provide leadership, advocacy and education with a focus on membership value, industry outreach and issues impacting the global bearing industry.

ABMA website

ABMA on wikipedia

Absolute Encoders

Absolute encoders are type of digital encoder. Like the incremental encoder they use the LED type transference of information, but instead of a pulse train the information creates a word of information which is either a binary, binary coded decimal, or a grey coded word. This word is unique for every rotational position 0 to 360 degrees and the results are that no reading errors can occur. If power is lost the position is not lost. They are also highly accurate. They are more expensive than the incremental encoder and generally as reliable.

Read more about Encoders

Absolute Synchronization (Electronic Line Shafting)

Absolute Synchronization is one of two methods of electronic synchronization. In absolute synchronization the remaining error of the analog synchronization is fully compensated for, providing an exact match of the two drive motor shafts with respect to speed and angular position.

Read more about Synchronizing Variable Speed Drives

AC Induction Motors

SEW-Eurodrive's DT/DV squirrel-cage induction motors and brakemotors deliver exceptional performance and reliability combined with low maintenance. The high-quality design and construction meet the standards of AC inverter/vector duty motors. In addition, the low-noise, lowinertia, and continuous-duty rating of SEW's brakemotors meet the demands of major applications that require fast, safe braking under tough service conditions.

Read more about AC Induction Motors

AGMA - American Gear Manufacturers Association

The American Gear Manufacturers Association is a voluntary association of companies, consultants, and academicians with a direct interest in the design, manufacture, and application of gears, couplings and related power transmission components and equipment.

AGMA website


ALTEMP Q NB 50 is a white/beige lubricating paste with a mineral base oil, barium complex soap and inorganic solid lubricants. The raw materials contain no lead, cadmium, nickel, sulphur or halogens. This lubricating paste is universally applicable for assembly purposes
and is especially suitable for friction points subject to small and very small sliding movements under high static and dynamic loads. It also provides reliable protection against fretting corrosion.

Read more about ALTEMP Q NB 50

Analog Synchronization

Analog Synchronization is one of two methods of electronic synchronization. The underlying principle in analog synchronization is that the same speed command signal is supplied to each drive

Read more about Synchronizing Variable Speed Drives

Backlash in Gearing

Backlash for any reducer is defined as the total air gap between the gear set or gear sets, measured at the output gears at the gear pitch diameter, with the input shaft held stationary.

The backlash is usually indicated under no load and is not to be confused with a torque wind-up or twist that results when a significant torque load is applied to the output shaft with the input shaft held stationary.

For many applications, the amount of backlash has little importance. Gears which are driving in only one direction, with no reversals of torque will have their driving faces continually in contact. As there is a sufficient backlash for thermal growth of the gears, backlash is not a concern to the user.

Read more about Backlash in Gearing

Bevel Gears

A type of gear with cone-shaped tooth-bearing surfaces cut at an angle. Bevel gears are often used in angular gear trains. They can be used to change the direction of drive in a gear system by 90 degrees.

Brake Reaction

At the instant the motor power ceases, energy stored within the brake coil must decay as rapidly as possible in order to stop the motor quickly. Fortunately, the weaker magnetic field that holds the pressure plate is advantageous not only during operation, but also during stopping. Its low current provides minimal heat while the motor is operating. And, its low energy allows it to decay quickly.

Nonetheless, the holding coil may be wired so that its low energy decays even faster. With appropriate wiring, all SEW rectifiers can convert the residual energy into heat using a varistor.

Normal Reaction
Normal reaction is commonly used for horizontal applications with a low duty cycle or those that do not require the most precise stopping distance. Since there is no additional
resistance in the path besides the coils, the residual coil energy must decay naturally.

Fast Reaction
Fast reaction is required for applications with a high duty cycle and applications that require the best position accuracy. On vertical applications that work against gravity, such as palletizers and lifts, fast reaction minimizes the stopping distance on downward motion and minimizes the downward drop that could occur when stopping during upward motion.

All rectifiers that mount within a control panel may be wired for fast reaction by using an auxiliary contact from the motor starter. However, the BG and BGE rectifiers that mount within the motor conduit box may be wired in one of three ways:
1. Auxiliary contact from motor starter
2. SR Relay
3. UR Relay (commonly used with inverter)

Brake Release

At the instant the motor receives power, the brake must release as quickly as possible. Otherwise, the motor works against the brake, producing excessive wear on the brake lining and additional heat inside the motor. Thus, fast release provides longer brake life, longer periods between brake adjustments, and a higher duty cycle.

All SEW brakes contain a patented holding coil (Patent 5,278,483) that consists of two separate windings: the accelerator coil and the fractional coil.

The accelerator coil contains a few turns of large diameter wire with low resistance. Low resistance produces high current and strong electromagnetism.

The fractional coil contains more turns of smaller diameter wire with higher resistance, producing lower current and weaker magnetism.

Centralized Systems

In centralized installation concepts, the drive electronics for controlling individual machines or system modules are housed in control cabinets, and a PLC has overall control. The alternative to Centralized Systems are Decentralized Systems.

More about Centralized versus Decentralized Systems

Complete Drive Management – CDM®

Modern maintenance is gaining in importance under the aspects of LCC (Life Cycle Costing), TCO (Total Cost of Ownership) and TPM (Total Productive Maintenance). The CDM® maintenance management offers a complete package with individual service modules to ensure the availability of expensive machines and systems.

Read more about Complete Drive Management – CDM®

Complete Drive Service – CDS®

Comprehensive and integrative services that can be tailored to the specific needs of every phase of the product life cycle make the CDS® Complete Drive Service the perfect solution for any requirement.

The individual and perfectly combinable CDS® system modules always provide exactly the service you need for your drive technology – no matter when and where you need it.

Read more about Complete Drive Service – CDS®

Condition monitoring designations

Designation  Option 
/DUO  Diagnostic Unit Oil = Oil aging sensor 
/DUV  Diagnostic Unit Vibration = Vibration sensor 

Current Sensing Device

A current sensing device can be a set of heater coils in a motor starter, or a set of fuses which are installed in series with the motor windings.

Current sensing with thermal heater coils or fuses is effective and sufficient if a motor runs continually at rated load and speed.

A motor is designed to operate at its nameplate current continuously. If an over-current condition exists, the motor could overheat and burn-out.

Current sensor's job is to detect the over-current and shut the power off to the motor to prevent burn out.

The current sensors are usually slow reacting which means they open up when the high current draw persists for several seconds (10 or more seconds). This time period depends on the size of the motor or application.

Decentralized Systems

In decentralized installation concepts, the components and functions are standardized and have a modular structure. The control intelligence is located in the drive technology or the module itself. The benefits of decentralized system include: Reduced Follow-up Costs, Reduced Installation Costs, and Reduced Energy Costs.

With up to a 60% reduction in installation costs with a decentralized structure, especially in extremely large production plants, decentralized installation concepts can cut costs considerably.

In comparison to centralized solutions, less space is needed for control cabinets, and significantly less cabling work is required; the control units are already integrated into SEW-Eurodrive’s decentralized drive components.

More about Decentralized Systems

Designing for Inertia

Inertia is resistance to a change in motion. It is determined by an object’s size, shape, and mass. The greater the inertia, the greater is the amount of force (torque) required to change the object’s state of motion.

During acceleration, the motor must produce enough torque to accelerate both its rotor and the load. An inertia acceleration factor, Jratio, is the ratio between the load inertia and the motor inertia. It is an important factor that determines system stability and reducer service factor. If Jratio is too high, the motor cannot stabilize the load and the application has ‘inertia mismatch’.

Read more about Designing for Inertia

Dimension designations of gearmotors

Total length of gearmotor 
LS  Total length of gearmotor including brake 
LB  Length of motor 
LBS  Length of brakemotor 
AC  Diameter of motor 
AD  Center of motor shaft to top part of terminal box 
ADS  Center of brakemotor shaft to top part of terminal box 


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DRL motors

Asynchronous servomotors of the DRL series are a drive package made up from the many options of the modular DR motor system. In its basic variant, the drive package always contains:

• Encoder, sine signals and electronic nameplate
• Thermal motor protection
• Dynamics package
• Various connection options
• Winding optimized with respect to speed

Depending on the application and requirements, the following elements can be added:
• Forced cooling fan
• Connection via plug connectors instead of terminals
• Temperature detection
• And many more

Alternatives can be selected instead of the elements of the basic variant, e.g. an absolute encoder instead of the sine encoder.

SEW-EURODRIVE offers the DRL servomotors with 4 rated speeds:
• 1200 rpm
• 1700 rpm
• 2100 rpm
• 3000 rpm

DRL series - Asynchronous servomotors

Asynchronous servomotors are the link between the classical asynchronous AC motors for supply system and inverter operation and the highly dynamic synchronous servomotors with permanent magnets.

Ductile Iron Gear Housing

Ductile iron, also called nodular iron due to its contents of graphite nodules in its structure, is a cast iron which has magnesium added to it as an alloying element. The added magnesium makes the ductile iron stronger and stiffer than gray iron and more shock resistant.

Read more about Gray Cast Iron vs Ductile Iron Gear Housings

EISA Law – SEW Compliance

On December 19, 2007, the Energy Independence and Security Act of 2007 (EISA) was signed into law. Its effective date is December 19, 2010. Therefore, all units shipped from SEW after December 19, 2010 must comply.

View minimum efficiency requirements of electric motors

Electronic Line Shafting

see absolute synchronization

Electronic Synchronization

Electronic synchronization involves independent variable speed drives that electronically forced to operate in synchronism. Electronic synchronization is often simpler to install than mechanical synchronization since the majority of the mechanical parts have been eliminated and in many cases is more economical. Additionally the speeds of the independent drives can be ratioed very easily via thumbwheel or potentiometer adjustments.

Two methods of electronic synchronization are used; one is termed analog synchronization and the other absolute synchronization.

Read more about Synchronizing Variable Speed Drives


Encoders are used in a variety of applications to sense both speed and position. The type of encoder chosen for a given application is strictly dependent on the application. Encoders are available in two basic types, analog and digital, and each have various output configurations.

Read more about Encoders

F-Series Gear Reducer - theSnuggler®

The SEW-Eurodrive F-series gear reducer, like the R-series, contains either 2 or 3 helical gear  stages and an offset-parallel shaft design. However, unlike the R-series, the F-series has a slimmer profile and is available with a hollow shaft.

Read more about F - Series

View SEW-EURODRIVE full line of products


Gear is a toothed wheel that engages with another toothed wheel or with a rack in order to change the speed or direction of transmitted motion. Gears are integral parts of Gearmotors.


Gearmotor is a type of electrical motor with various output speeds secured by combinations of gears.

Helical gear units designations

RX..  Single-stage foot-mounted type 
RXF..  Single-stage B5 flange-mounted type 
R..  Foot-mounted 
R..F  Foot and B5-flange mounted type 
RF..  B5 flange-mounted 
RZ..  B14 flange-mounted 
RM..  B5 flange-mounted type with extended bearing hub 

Helical Gears

Helical gears have angled teeth compared to straight teeth found on super gears. This angled design of the teeth causes them to engage other gears gradually, rather than all at once. This gradual engagement and disengagement provides smoother and quieter operation. Helical gears are also stronger and last longer than spur gears. Helical gears allow for application of gears mounted on perpendicular shafts

Helical-bevel gear units designations

K..  Foot-mounted 
KA..B  Foot-mounted, hollow shaft 
KH..B  Foot-mounted, hollow shaft with shrink disk 
KV..B  Foot-mounted, hollow shaft with splined hollow shaft to DIN 5480 
KF..  B5 flange-mounted 
KAF..  B5 flange-mounted type and hollow shaft 
KHF..  B5 flange-mounted type and hollow shaft with shrink disk 
KVF..  B5 flange-mounted type and hollow shaft with splined hollow shaft to DIN 5480 
KA..  Hollow shaft 
KH..  Hollow shaft with shrink disk 
KT..  Hollow shaft with TorqLOC® hollow shaft mounting system 
KV..  Hollow shaft with splining to DIN 5480 
KAZ..  B14 flange-mounted type and hollow shaft 
KHZ..  B14 flange-mounted type and hollow shaft with shrink disk 
KVZ..  B14 flange-mounted type and hollow shaft with splined hollow shaft to DIN 5480 

Helical-worm gear units designations

S..  Foot-mounted 
SF..  B5 flange-mounted 
SAF..  B5 flange-mounted and hollow shaft 
SHF..  B5 flange-mounted and hollow shaft with shrink disk 
SA..  Hollow shaft 
SH..  Hollow shaft with shrink disk 
ST..  Hollow shaft with TorqLOC® hollow shaft mounting system 
SAZ..  B14 flange-mounted and hollow shaft 
SHZ..  B14 flange-mounted and hollow shaft with shrink disk 

Hypoid Gearing

Hypoid gears are members of the skew-axis gear family resembling spiral bevel gears but the axes the pinion and driven gear do not intersect. These gears operate between the extreme operating positions of bevel gears and worm gears.

The geometry of the hypoid gearing permits the driving and driven shafts to continue past each other so that end-support bearings could be mounted. By supporting both ends of the driving shaft a greater rigidity may be attained than is provided by a cantilever design of similar proportions.

Read more about Hypoid Gearing

Incremental Encoders

The most common of encoders, incremental encoders are a digital encoder. Their operation is based on a light emitting diode (LED) passing light through a series of holes in a disc. This light is detected  on the other side and then processed into usable information. Incremental encoders are available in a wide variety of output configurations which makes them very flexible and for the most part are reliable. One major disadvantage is if power is lost, position information is lost.

Read more about Encoders

IOP (Industry Option Package) For Food

Food processing plants must be cleaned and disinfected regularly to maintain sanitary operating conditions. High-pressure hoses and corrosive cleaning solutions are commonly used within this environment. Gear reducers and motors often experience a high failure rate for the following reasons.

• Cleaning solution is often forced into the motor, causing electrical shorts
• Cleaning solution is often forced into the reducer, causing seal deterioration, oil contamination, loss of lubricity, and rust
• Protective paint coatings are often stripped away, causing rust or other detrimental chemical reactions

SEW's solution is the Industry Option Package for Food (I01). The I01 combines a number of upgraded motor and reducer features into a single option package specifically designed to extend the life of drives used in the food industry.

Read more about IOP (Industry Option Package) For Food

IP Enclosures

IP is an international standard for protection of an electrical apparatus including motors, pushbuttons, electronic devices, etc. It is designated by the letters IP followed by two numbers. The first number states the category of protection against operator contact and protection against intrusion of foreign objects. The second number states the category of protection against the entry of water

View chart explaining the categories of each protection

K-Series Gear Reducer

The SEW-Eurodrive K-series reducer contains three gearing stages: 1st stage – helical, 2nd stage – bevel, 3rd stage – helical. Efficiencies are comparable to SEW's R-series and F-series helical reducers.

Read more about K-Series Gear Reducer

Klüberpaste UH1 84-201

Klüberpaste UH1 84-201 is a white lubricating and assembly paste authorized in accordance with USDA-H1. It contains a fully synthetic base oil and a thickener consisting of a mixture of organic and inorganic solid lubricants.

The raw materials contain no heavy metals or sulphur.

Klüberpaste UH1 84-201 is universally applicable as an assembly paste and particularly suitable for lubrication points operating in a humid environment. The paste is very resistant to water, shows good anticorrosion behaviour and is compatible with high-alloy steels.

Read more about Klüberpaste UH1 84-201

Mechanical Synchronization

Typically mechanical synchronization involves a single drive motor that is connected to multiple driven machines via various line shafts, couplings, miter gear units, belts, sheaves, chains, sprockets, etc.

As the number of driven pieces of equipment increases, the amount of mechanical parts required to achieve synchronization increases tremendously. Additionally as the distances from the drive motor to the driven equipment increases, mechanical synchronization may be impractical.

But there are many applications where mechanical synchronization is the preferred method. A roller conveyor for transporting pallets with several "live" rollers could use mechanical synchronization of the "live" rollers very efficiently. The live rollers can be interconnected to the drive motor via gears or chains and sprockets mounted on the axle of each live roller fairly easily. Providing a drive motor for each roller and electronic synchronizing each motor may be too "sophisticated".

Read more about Synchronizing Variable Speed Drives

Metric Flanged Mounted Motors

Internationally the flange dimensions of metric frame motors have been standardized similar to the NEMA standard flange dimensions found in the USA. Two of the more common styles of metric flanges found are referred to as B5 (similar to NEMA D flange) and B14 (Similar to NEMA C-Face) flanges.

Read more about Metric Flanged Mounted Motors

NEMA Electrical Control Enclosures

Enclosures for electrical controls and electronic equipment such as pushbutton enclosures, junction boxes, cabinets, etc., are designed by NEMA according to the degree of environmental protection given to the enclosed equipment.

View list of common NEMA types of enclosures

NEMA Electrical Motor Enclosures

Per NEMA standard MG1 Motor Enclosures are classified according to environmental protection and methods of cooling.

See definitions of the common motor enclosures

NEMA National Electrical Manufacturers Association

The National Electrical Manufacturers Association (NEMA) is the association of electrical equipment and medical imaging manufacturers. Founded in 1926 and headquartered in Rosslyn, Virginia, its 400-plus member companies manufacture a diverse set of products used in the generation, transmission, distribution, and end use of electricity as well as medical diagnostic imaging. Total U.S. shipments for electro industry products exceed $100 billion annually.

NEMA provides a forum for the development of technical standards that are in the best interests of the industry and users, advocacy of industry policies on legislative and regulatory matters, and collection, analysis, and dissemination of industry data. In addition to its headquarters in Rosslyn, Virginia, NEMA also has offices in Beijing and Mexico City.

Oil expansion tank

The oil expansion tank allows the lubricant/air space of the gear unit to expand. This
means no lubricant can escape the breather valve at high operating temperatures.

SEW-EURODRIVE recommends to use oil expansion tanks for gear units and gearmotors
in M4 mounting position and for input speeds > 2000 rpm.

Options designations

R, F and K gear units:

/R  Reduced backlash 

K, S and W gear units:

With torque arm

F gear units:

With rubber buffer

Parallel shaft helical gear units designations

F..  Foot-mounted 
FA..B  Foot-mounted, hollow shaft 
FH..B  Foot-mounted, hollow shaft with shrink disk 
FV..B  Foot-mounted, hollow shaft with splined DIN 5480
FF..  B5 flange-mounted 
FAF..  B5 flange-mounted type, hollow shaft 
FHF..  B5 flange-mounted type and hollow shaft with shrink disk 
FVF..  B5 flange-mounted type and hollow shaft with splined hollow shaft to DIN 5480
FA..  Hollow shaft 
FH..  Hollow shaft with shrink disk 
FT..  Hollow shaft with TorqLOC® hollow shaft mounting system 
FV..  Hollow shaft with splining to DIN 5480 
FAZ..  B14 flange-mounted type, hollow shaft 
FHZ..  B14 flange-mounted type and hollow shaft with shrink disk 
FVZ..  B14 flange-mounted type and hollow shaft with splined hollow shaft to DIN 5480

PI Loop

Internally, Movidrive® inverters contain a PI (Proportional-Integral) loop for speed control, similar to cruise control in an automobile. At a given moment in time, a PI Loop measures the motor's actual speed and compares it to the desired setpoint speed. The difference is the error. Based upon this difference, the error correction process of the PI Loop makes appropriate adjustments to the drive's performance, with the goal of having zero error and having the actual speed equal to the desired speed at the next measurement.

Read more at Interpreting MoviTools® Scope


Post magnetization – maintains a magnetic field on the motor for at least 100ms after the motor stops so that the motor does not move (freefall) before the brake is applied.

PT Pilot® - Drive Selection Tool

PT Pilot® - Drive Selection Tool makes selecting a custom reducer or gearmotor fast and easy! PT Pilot® is SEW-EURODRIVE's cutting edge online selection tool with no installation or purchase requirement.

Read more about PT Pilot®

Reflected Wave Phenomenon

See Reflected Wave Phenomenon article


Resolvers are type of analog encoder. The princile of operation is based on the rotating transformer. It has a rotor winding with two stator windings placed at 90 degrees to each other. With a given input signal, the output is a two channel sine and sosine signal. The two signals are then processed and translated into speed and position. The advantages to resolvers are that they are tolerant to high temperatures (above to what motors can handle), are not sensitive to vibrations and are easy to connect. There is no real selection criteria and they are primarily used in servo motors.

Read more about Encoders

RM gear units, RM gearmotors

RM gear units and RM gearmotors are a special type of helical gear units with an extended output bearing hub. They were designed especially for agitating applications and allow for high overhung and axial loads and bending moments. The other data are the same as for standard helical gear units and standard helical gearmotors.

Scoop Mounting for Motors

A scoop is a motor mounting base which is attached to and supported by the reducer. It's advantage is in the fact that additional platforms are not required. Since reducer housings are designed to transmit only forces developed from its rated torque and its own weight, certain restrictions must apply when using scoops.

Read more about Scoop Mounting for Motors

Severe Duty Motors

Motors operating outdoors or within chemical or food processing plants are subjected to corrosive conditions. Large temperature and humidity variations draw moist air inside the motor's stator. As the motor cools, the moist air condenses. As the condensation accumulates, corrosion occurs. Eventually, corrosion degrades the wire insulation, causing the windings to short and the motor to fail. SEW-Eurodrive motors and brakemotors are available with Severe Duty (-KS) protection. This option is available with induction motors, permanent magnet servomotors, and Movimot® motors.

Read more about Severe Duty Motors


SEW is an acronym for Süddeutsche Elektromotoren Werke

Single Phase Motors

Single phase AC motors come in several versions. The most common types are:

• Split-Phase Motors
• Permanent Split-Phase Motors
• Repulsion Type Motors
• Shaded Pole Motors
• Capacitor Start - Induction Run Motors
• Capacitor Start - Capacitor Run Motors

Read more about Single Phase Motors

SPIROPLAN® gear units designations

W..  Foot-mounted 
WF..  Flange-mounted 
WAF..  Flange-mounted type, hollow shaft 
WA..  Hollow shaft 
WA..B  Foot-mounted, hollow shaft 
WH..B  Foot-mounted, hollow shaft with shrink disk 
WHF..  Flange-mounted, hollow shaft with shrink disk 
WH..  Hollow shaft with shrink disk 
WT..  Hollow shaft with TorqLOC® hollow shaft mounting system 

SPIROPLAN® right-angle gear units/gearmotors

SPIROPLAN® right-angle gearmotors are robust, single- and two-stage right-angle gearmotors with SPIROPLAN® gearing. The difference to the helical-worm gear units is the material combination of the steel-on-steel gearing, the special tooth meshing relationships and the aluminum housing. As a result, SPIROPLAN® right-angle gearmotors are wear-free, very quiet and light.

The particularly short design and the aluminum housing make for very compact and lightweight drive solutions.

The wear-free gearing and the life-long lubrication facilitate long periods of maintenance-free operation. The fact that the oil filling is independent of the mounting position, except for SPIROPLAN® W..37 and W..47 in mounting position M4, makes any position possible for SPIROPLAN® right-angle gearmotors without having to alter the oil quantity. Identical hole spacing in the foot and face, as well as the equal shaft height to both, provides you with diverse mounting options.

Two different flange diameters are available. On request, SPIROPLAN® right-angle gearmotors can be equipped with a torque arm.

Swing base

A swing base is a drive unit consisting of helical-bevel gear unit, hydraulic centrifugal coupling and electric motor. The complete arrangement is mounted to a rigid mounting rail.

Motor swings are available with the following optional accessories:
• Torque arm
• Mechanical thermal monitoring unit
• Contactless thermal monitoring unit


Tachgenerators are type of analog encoder. They were designed primarily to provide speed regulation which in effect widens the speed range for dc motor applications and are still used today. The principle of a achgenerator is that they provide a DC output voltage based on speed of their armature. They are low in cost and very reliable.

Read more about Encoders

Temperature Sensing Device

A temperature sensing device, such as a thermistor or thermostat, monitors the temperature of the motor winding. It does not monitor current draw.

Read more about Thermistors and Thermostats

The Energy Independence and Security Act of 2007 (EISA 2007)

The Energy Independence and Security Act of 2007 (EISA 2007) is an act to move the United States toward greater energy independence and security, to increase the production of clean renewable fuels, to protect consumers, to increase the efficiency of products, buildings, and vehicles, to promote research on and deploy greenhouse gas capture and storage options, and to improve the energy performance of the Federal Government, and for other purposes.

Read more about EISA 2007

Thermal Ratings and Limitations

Gear reducers must withstand both mechanical and thermal influences in order to ensure sufficient life of the bearings, gears, oil and seals. Factors that limit the amount of torque that can be transmitted through the gear reducer include the required bearing life hours plus the strength of the gears, housing, keys, and output shaft. The mechanical torque rating must ensure that the gears and shafts can achieve an infinite fatigue life and that the bearings can achieve at least a finite number of hours. The lower the load torque is compared to the mechanical torque rating, the higher the service factor and the longer the bearing life.

Read more about Thermal Ratings and Limitations


A thermistor is a solid state device which is embedded in the windings of a motor. This embedding is done in the motor manufacturing department.

A thermistor operates as a temperature sensitive variable resistor whose resistance rises very rapidly when a certain trip temperature is reached. This trip temperature is a function of the insullation class of the motor windings. Motors, therefore, can be supplied with thermistors for B, F and H insulation protection.

Read more about Thermistors

Thermistor Motor Protection Monitoring Relay

Motors utilizing thermistor protection may use an external monitoring relay to evaluate the temperature of the motor for acceptable and unacceptable levels. The thermistor monitoring relay approved by SEW-Eurodrive, USA is the CM-MSS 1SVR430720R0400 by ABB.

Find out more about Thermistor Motor Protection Monitoring Relay


A thermostat is a solid state device or bimetal switch which is usually installed in or against the winding head of the motor. This thermostat is glued or epoxied against the winding head.

A thermostat operates as a normally closed switch when a motor is in a cooled-off condition and opens above the trip temperature. Thermostats can be selected for protection of motors with B, F or H insulation, and open-up at different temperature levels depending on their design.

Read more about Thermostats


The patented SEW TorqLOC® offers an alternative to a keyed shaft. It utilizes friction force instead of shear force to transfer torque. Because TorqLOC® contacts the user's shaft at only two locations–the support bushing and the torque bushing – and because these parts are made of bronze, stainless steel, or electroless nickel plating, the likelihood of corrosion is very minimal. Moreover, the same clamping pressure that creates torque also helps to prevent oxidation and corrosion at the contact area of the torque bushing.

SEW's patented TorqLOC® is the premier choice for a keyless hollow shaft connection. Due to its corrosion resistance and ease of installation, it is highly recommended in wet environments or in applications where a concern for safety prohibits the use of belts and chains.

Read more about TorqLOC®

TorqLOC® Versus Keyed Shaft

TorqLOC® Advantages

TorqLOC® Covers

TorqLOC® with Flange

Torque Control

Torque Control – requires the motor to produce a predetermined torque at all times, regardless of speed. If the load torque is less than the predetermined torque, the motor rotates faster and faster – a very undesirable situation.

Torque Limit

Torque Limit – allows the drive to operate to a certain torque. As long as the predetermined torque is not reached, the drive operates normally. When the predetermined torque is reached, the motor slows or stops.

Torque Motors

A torque motor is rated by torque in lb-in. and not in horsepower. The torque rating of a torque motor is that torque which the motor can develop at a continuous stall without burning out from overheating. In addition to the continuous stall, the torque motor can operate in the same fasion as a standard motor. It can be plug reversed, braked, rotated CW or CCW, etc.

The difference between a standard motor and a torque motor is as follows: When a standard motor develops its breakdown torque, it will come to a stop, it draws very high current, and if not disconnected from the line, it will burn out. A torque motor will continue to generate its rated torque when it is stalled out (to 0 rpm). To get more torque out of the motor, a gear reducer can be mounted integrally with the motor. The reducer will then work as a torque multiplier. The torque motor can be used in many applications.

Read more about Torque Motors

Total Cost of Ownership (TCO)

Total Cost Of Ownership - TCO, is a sum of all costs incurred during the life cycle of a system. These costs include Energy, Startup, Training, Optional equipment, Spare parts, Maintenance / service, Personnel, Controlling, Reliability, Replacement system procurement, Retrofitting, and Disposal. Energy efficient decentralized systems offered by SEW-EURODRIVE have lower Total Cost of Ownership, compared to traditional centralized systems.

More about Total Cost of Ownership (TCO)

Type DA Programmable Digital Tachometer

The Type DA meter is an economical microprocessor based digital tachometer system capable of measuring low shaft speeds. An on-board cicrocomputer coupled with sophisticated internal software, quartz crystal controlled reference frequency, and display up-dating on every pulse or every 0.5 seconds (whichever is longer), permits accuracy of +/-0.04%.

Read more about Type DA Programmable Digital Tachometer


Varigear® is SEW-Eurodrive's Mechanical Variable Speed Belt Drive, Type VU/VZ, available from 1/2 to 60 horsepower with a maximum speed range of up to 8:1.

Find out more about Varigear®

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