Focus on Sci. & Tech. Grasp Details

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3 Focus on Sci. & Tech. Grasp Details B Series Safety brake, adopts modular design and has multiple functions, which can facilitate super rapid response with its professionally designed for low power electromagnetic coils, delicately upgraded magnetic circuit structure and special circuit board. S Series Safety brake, of high corrosion resistance and high protection, can be directly applied in open air. C Series Power-on brake, keeps interchangeability with the majority of mainstream product in the market, for extensive application. P Series Power-on brake, with backlash compensation and torque adjustability, is developed by UHT specifically for various electric cars. BH Series UHT developed the brake specifically for wind power field with features as highly-sealed and highly corrosion resistant, which can be uni-directional or bi-directional. Meanwhile we can design brakes with specific functions according to personal needs of customers.

4 Company Profile Catalog Brake Model Selection B Series- Spring-loaded Electro-magnetic Brake Features& Applications Operation Principle Rated Data Instruction for Installation Installation Dimension Table Instruction for Adjustment Attachments Product Definition Selection Form S Series- High Sealing Spring-loaded Electro-magnetic Brake Features& Applications Operation Principle Installation Dimension Table Instruction for Installation and Adjustment Product Definition Selection Form C Series- Spring-loaded Electro-magnetic Brake Features& Applications Operation Principle Installation Dimension Table Instruction for Installation Selection Product Definition Selection Form Rectifier Application for Crane Application for Wind Power Application for Forklift Truck Definition of symbols Braking torque required for dynamic load : Braking torque required for both dynamic and static load : Decelerating torque : Load torque : Rated torque of brake : Load moment of inertia : Relative rotation speed : Braking power : Friction power : Kinetic energy of gravity load : Quality of gravity load : Gravitational acceleration : Brake delay time : Friction coefficient : Friction plate equivalent radius : Friction torque : The resultant force on the armature : The spring force on the armature : The electromagnetic force produced by coil

5 Brake Model Selection Brake model selection depends totally on type of brake application. B Series brakes can be applied to general situations like power-off braking; S Series of high protection class for environments with more dust or outdoors; crane dedicated brakes for hoisting purpose; low-noise brakes for elevators, stages and other cases of low noise request. If you have special requirements on the response time or other functions of brakes in application environments, please contact suppliers. After the confirmation of brake model, the braking torque should be calculated based on the condition of loading. The calculation rules are shown below: Safety factor: K 2 Load calculation: The dynamic load is usually calculated according to the following formulas: Generally, both dynamic load and static load coexist in practical use, M load ). K M k when the braking torque and static torque have the same direction when the braking torque and static torque have the opposite directions With the known power of brake motor, the braking torque can be estimated according to the following formula: Calculation of friction power: If the braking frequency is very high and the frictional power consumption for each braking is large, the thermal load needs to be considered. The formula for calculating frictional power consumption is as follows: when the braking torque and static torque have the same direction when the braking torque and static torque have the opposite directions Notice: When calculating the friction power in the process of descent in the field of hoisting, the kinetic energy converted from the gravitational potential energy of load during the process of braking delay should also be considered in addition to the inertia of the system. The specific value should be: The actual friction power with gravity load is:

6 B Series Spring-loaded Electro-magnetic Brake Features: Power-off braking.insulation class of 155. Adjustable air gap, and long life. UHT offer products with low noise, corrosion resistance, high sealing and modular design for custom to choose Applications: Escalators, Lifts Port Machinery Crane Metallurgy Machinery Material Handling Machinery Light Industrial Packaging Textile and Printing Wood Working Machines Electrical Vehicles and Forklift Wind Mills

7 B Series Operation Principle 1.Hollow screw tube 2.Hub 3.Flange 4.Rotor 5.Friction plate 10.Screw 9.Stator 8.Springs When braking, the Rotor (4), which is installed on the Hub (2) with the splines, will be pushed by Springs (8) towards Flange (3) through Armature Plate (6), so as to produce the braking torque and the air gap generated between armature plate and Stator (9). When the brake is released, the Stator Coil (7) will be driven by DC current, and the magnetism generate force produced would make Armature Plate (6) push Springs (8) to draw to the stator, when the Rotor (4) is released, braking action is cancelled. 7.Coil 6.Armature Axial movement component Rotating component = = F F F Fixing component Assembling surface = page 7

8 B Series Rated Data Torque range For different applications, see table for the related torque value matched with the frame size: Rated torque(nm): value at Δn=100rpm Decelerating braking Load maintains rotating state because of inertia when loss of power, the friction pair keeps acting to consume residual kinetic energy to brake. Maintaining braking Rated brake torque that manufacturer offer to customers. Standard braking torque The braking strategy taken to keep position state or potential energy state of load, while the friction pair is in compressed state without relative displacement. > The impact of speed on braking torque Rated brake torque at Δn=100rpm (100%) Relationship between brake torque & Δn(rpm) (%) Maximum speed Maximum speed (rpm)

9 Response time Response time is the response time of the DC switch under 20 and rated air gap. The time depends on the value of S and adjustment method to a large extent. The braking response time of DC switch is at least 10 times faster than AC switch. Rated braking torque (Nm) Permissible friction work per cycle [J] Brake frequency under permissible friction (times per hour) The braking response time of DC switch Power relaxation time t2 ms Please take overexcitation rectifier when faster response is needed, waveform as showed below:

10 Rated Data Rated torque Nm Rated capacity W Rated air gap mm Handle gap mm S max Decelerating braking mm S max Maintaining braking mm Min Rotor thickness mm Max Rotor thickness mm Moment of Inertia J(Kgcm 2 ) Adjusting nut trip(mm) Mounting hole diameter(mm) Number and specification of mounting screw Locking torque of mounting screw (Nm) Weight of stator Standard Voltage: 24VDC,103VDC,180VDC,205VDC. Mk:Rated torque which is measured at the relative speed Δn=100rpm Coil power (P) is the value at 20, allowable ±10% at different input voltage. Thickness of friction plate is designed that adjustment value of wear quantity is at least 5 times of rated air gap. The length of mounting screw depends on installation method of the brake. > Permissible friction work depends on the brake frequency. Frequency (times per hour)

11 B Series Instruction for Installation 3.Rotor 10.Screw 7.Stator 4.Hub 5.Shaft 6.Friction plate If no suitable friction surface is available, a flange or Friction Plate (6) can be installed as showed in the picture. Fix Hub (4) on Shaft (5) axially. A clearance of 0.5-1mm is usually maintained between the hub and the installation surface so as to avoid obstructing the rotation of the shaft. The existence of this gap prevents collision between the hub and the friction dual faces in excessive axial movement. Do not knock the hub brutally; avoid inclined assembly. To preclude axial float of the hub, please fix it on the shaft with a C clip ring. Install Rotor (3) on Teeth Hub (4). The rotor and hub tooth should be alignment, wheel pushing instead of knocking brutally. In order to lower noise, seal with silica gel between the hub involute tooth profile, and then load the rotor. Insert Set Screw (10) into the hole of Stator (7) and connect it to the corresponding friction surface. Locking torque see table. Dismantle the transport support. Check the gap. Ensure the friction surface is protected from lubricating oil or grease. Energized

12 B Series Installation Dimension Table (06-16 reference drawing) Standard Standard of keyway refer to GB/T1095, the choice of shaft diameter depends on the type of load, standard of shaft hole marked with refer to GB/T1566. Unit:mm.

13 (18-30 reference drawing) L1 is the wire length. Unit: mm

14 B Series Instruction for Adjustment > Data of installation and adjustment Rated air gap S Max air gap S max Handle gap S1 Tightening torque(nm) Allen wrench size(mm) Open end wrench size(mm) Service life (adjustment) Adjustment is needed once the brake air gap S reaches the Smax. Friction power consumption is a function of a multitude of factors, such as moment of inertia, braking speed, braking frequency and friction surface temperature. Therefore it is necessary to make some adjustment so as to keep the friction power consumption in an optimum status. > Installation of hand release The hand release may be installed after the brake is assembled. Firstly insert the bolt with shim and springs in the pre-opened hole so that it runs through the armature and the magnet, then install the release handle, and have it connected to the handle pin.

15 > Adjustment of air gap While the bolt loosened and power off, rotate the hollow screw tube so that the air gap is adjusted to the rated value in the table with the aid of a feeler gage. Mind that the gap is uniform on the entire perimeter. Tighten the bolt after the desired air gap is obtained. The rated air gap S increases as a result of wearing. To ensure the brake provides sufficient braking torque, the air gap must be adjusted before it reaches the maximum value (Smax) indicated in the table. The adjustment may be made repeatedly. The brake noise is closely related to the air gap value; for application where low noise is required, it is recommended to adjust the gap before it reaches the maximum value. Too excessive an air gap may result in release failure of braking power or reduced braking torque and holding torque, or even lead to serious accidents. Therefore it is imperative to check and adjust the air gap when necessary. Note that the mains switch of the machine must be off before attempting any adjustment. Adjusting method: Check the brake air gap. Release mounting screws firstly if needed to adjust gap. > Attention for installation Tighten mounting screws. Use a wrench rotating hollow screw tube to adjust air gap, rotating clockwise sense to adjust bigger, anti-clockwise sense to smaller. For the friction dual faces, the surface roughness Ra shall not exceed 3.2, the surface shall be made of smooth cast iron or steel; the friction face shall be free of any sharp point. A friction disk or flange may be used where no suitable smooth face is available. The length of key of the fixed sleeve should be the same as the length of the sleeve keyway. Temperature: The insulation level of the brake is 155, the brake shall work at an ambient temperature of -20 ~50. Humidity and water droplets: If water droplets attached on the surface of friction, friction will be temporarily low before drying, please take the strategy of protection cover installation. The brake surface will produce gel when working in high temperature difference environment, which can be solved by using heating zone or high grade packaging. In addition water attachment will lead to rust, which may cause locking in serious situation. Ventilation: The brake had better install in well-ventilated environment, because friction power consumption is transformed into heat. If forced cooling by air blower, it is very effective to increase the friction work. Please

16 Antirust: Poor storage, harsh environmental conditions and other factors will cause brake rust. The friction surface of the serious corrosion will affect the braking torque, damage the friction surface, even cause locking, although slight corrosion will not. Sparks: Brake may produce sparks because of friction. Please consider the explosion-proof design if it is used in flammable and explosive environment. Magnetic shielding of stator: The brake influenced by the measurement instruments and machines In the vicinity of it may have noise or false action, which can be solved by magnetic shielding device. Non conducting magnetic material is usually used as the material of the mounting surface and shaft of the stator. Wire protection: Brake cable of UHT has many advantages such as UV protection, anti aging, cold resistance and heat resistance and so on. If the wire is damaged, it will cause short circuit or open circuit, which should be prevented at the beginning of the design. When screw the screw on flange through the brake, there should be a hole with Φ6 and depth no less than d1 between end covers of electric generators and flange, which ensure adjustment of air gap. While other installation method, make sure that depth of threaded hole on end covers of electric generators is no less than 3 times of d1. > Common Malfunction Analysis Coil anomalies (including coil short circuit, open circuit, and abnormal insulation): Measure coil resistance and insulation resistance with a multimeter and a megger, check whether coil resistance and insulation is good or not. If the coil resistance or insulation is abnormal, please replace the stator. Deviation of air gap and handle gap (including too-big or too-small): Check the gap with feeler to make sure it is in specified range. Control Sequence problem: Mismatch of the electric machinery start/stop control program and brake response time, may aggravate the wear, reduce service life of the brake and the electric machinery, and even worse, wear to out of service in 3-5 days or over burnt coil. Rotor life problem: Please replace the rotor when it wears to very thin. Line problem: Please check whether the line connection is normal. Action problem: Verticality between mounting end face and shaft is too big. Rectifier exceptionally: Please check whether Micro switch become invalid, check with a multimeter whether the micro switch contact can be triggered by braking normally and whether the micro switch can be triggered manually. If the micro switch cannot be triggered manually(broken) or it cannot be triggered by braking after adjusting, please replace the micro switch. > Instruction for use of the micro switch The micro switch is applicable to actuation detection and wear detection. Adjust the air gap between the armature and the stator to the standard value while actuation detection. After the brake is powered, test whether the micro switch has the ON/OFF signals with the multimeter. If there is not a signal, check whether the brake is released (i.e. the armature is drawed by the stator coil). If it is released, open the brake and adjust the screws on the armature, which touch the micro switch contacts, until the micro switch has the signal that the brake can be released; then tighten the screws with glue and nuts. The electric generators cannot be started until the micro switch has a signal. The micro switch s trigger position can be adjusted as well to realize the gap detection. When the air gap is too long, the micro switch will not be triggered, the generator s contactor cannot actuate, so the motor will not be started. In this case, adjust the clearance between the armature and the stator to the standard value. Actuation detection and wear detection cannot be done by the same micro switch. Only one of them can be chosen. If both actuation detection and wear detection are required, please inform the supplier. Nut Adjusting bolt Stator Micro Switch

17 > Accessories of B Series Brake > Handle The handle is used to release the brake manually. After the manual operation, handle can return to its original positions automatically. The release screws are installed inside the spherical hinges of the handle and are tensioned. Gap S1 is the distance between the armature and the spacer. When the handle is installed, gap S1 should be adjusted according to the tale below reference picture reference picture Gap partial enlarged drawing Unit

18 > Dust-shield The dust-shield can prevent external dust and other dirty things from entering the brake to a large extent. It covers the brake externally and is embedded into a groove. If there is not an appropriate groove in the motor s installation side, it is suggested a flange or a friction plate be used. Unit Friction plate If there is a well-processed surface on the machine body, which cannot be used as the friction surface, e.g. the aluminum shell, the friction plate can be used. Frame size of can be provided. Unit

19 Flange The flange can be used when there is not an appropriate friction surface on the machine to use. Unit Micro switch The micro switch can detect whether the brake is released and feed back a switching value signal, to prevent the generator starting when the brake is in the operating state and protect the motor effectively. The micro switch connection mode is showed in the picture NC NO Brown Gray Black NC NO Gray Blue Black (16-30 reference picture) (12 14 reference picture)

20 B Series Product Definition Special Order Code Oil sealed aperture mm Empty: No seal end cover and oil seal 0: Dust cover without holes Hub aperture mm Braking torque (Nm) Coil voltage VDC Attachment 0: None 1: Hand release 2: Dust-shield 3: Hand release + Dust-shield Friction pair 0: None 1: Friction disc 2: Flange Rotor material Empty: Aluminum rotor T: Stainless steel rotor Rotating part 0: None 1: Rotor 2: Hub 3: Rotor & Hub 4: Low noise hub 5: Rotor & Low noise hub : Note: L: Low noise armature J: Ultra-quiet structure S: Bolts self-locking Brake type N: Non-adjustable torque R: Adjustable torque NM: Non-adjustable torque & Micro switch RM: Adjustable torque & Micro switch Brake series No.

21 B Series Selection Form Customer Name Type Voltage Torque regulation N Adjustable torque R AC input voltage 110VAC 220VAC 380VAC 440VAC Others DC input voltage 24VDC 103VDC 180VDC 205VDC Others Braking torque Cable length Rotor standard Special please indicate the cable length mm Bare wire mm standard Aluminum rotor Stainless steel rotor Hub The aperture mm Key width mm Deep groove mm Friction pair Flange Friction disc Installation Method Screws on flange through the brake Screws on end covers of electric generators through the brake and friction plate Screws on end covers of electric generators through the brake and flange Screws on end covers of electric generators through the brake Micro switch Actuation detection Wear detection Seal Manual release Dust-shield Oil Seal, oil seal installation section of the shaft diameter mm The sealing cover is blocked Handle release Screw release Other, please contact our technical department to communicate Other requirements Special Applications Elevator/stage Chain hoist Wire rope hoist Brake type

22 Tianjin UHT Science and Technology Co.,Ltd. No.7, Xiangrui Road, Tianxiang Industrial Park, Xiqing Economic Development Zone, Tianjin Zip code: Tel: Fax: