FAQ about Drives Technologie

Transcription

1 FAQ about Drives Technologie Instructions and measures when storing the motors for longer periods of time - as well as commissioning and maintenance of low voltage motors Low Voltage Standard Motors

2 Warranty, liability and support We do not accept any liability for the information contained in this document. Any claims against us - based on whatever legal reason - resulting from the use of the examples, information, programs, engineering and performance data etc., described in this example shall be excluded. Such an exclusion shall not apply in the case of mandatory liability, e.g. under the German Product Liability Act ( Produkthaftungsgesetz ), in case of intent, gross negligence, or injury of life, body or health, guarantee for the quality of a product, fraudulent concealment of a deficiency or breach of a condition which goes to the root of the contract ( wesentliche Vertragspflichten ). However, claims arising from a breach of a condition which goes to the root of the contract shall be limited to the foreseeable damage which is intrinsic to the contract, unless caused by intent or gross negligence or based on mandatory liability for injury of life, body or health The above provisions does not imply a change in the burden of proof to your detriment. Copyright 2008 Siemens A&D. It is not permissible to transfer or copy these examples or excerpts of them without first having prior authorization from Siemens A&D in writing. For suggestions about this document please use the following address: mailto:sdsupport.aud@siemens.com Version issue January /22

3 Table of Contents Table of Contents Transport and storage Rotor shipping brace Short-time storage Long-time storage Commissioning Preparation Power-on Powering-down Maintenance Instructions for standard LV Motors Safety instructions Maintenance intervals Carrying-out an inspection Checking the insulation resistance Preparation Execution Values Greases and regreasing Grease designations according to DIN and Lubrication and relubrication intervals Vibration Vibration severity Apendix Internet links History This entry is from the Internet offer of Siemens AG, Automation and Drives, Service & Support. Clicking the link below directly displays the download page of this document. Version issue January /22

4 1 Transport and storage Only use the openings, lifting lugs and elements provided on the baseplates to transport machine sets (e.g. motor and coupled load)! It is not permissible to lift machine sets by just suspending them from the individual machines or motors! Carefully check the load capability of the hoisting equipment or crane being used to ensure that it is suitable! Individual motors may only be suspended from their main lifting lugs or rails provided for this purpose! Lifting equipment and cranes must be dimensioned and selected corresponding to the motor weight (for motors from shaft height 180 onwards, the weight is stamped on the rating plate). If the motors have additional mounted equipment, then please use suitable cable routing or spreader devices. If secondary lifting lugs are provided e.g. on fan shrouds, mounted coolers etc. then these are only suitable for lifting that particular individual component. 1.1 Rotor shipping brace Motors, e.g. with cylindrical roller bearings, individual angular-contact ball bearings or sleeve bearings, have an axial rotor shipping brace. This avoids bearing damage during transport. This rotor shipping brace may only be removed just before attaching the drive output element. If the motor has to be transported after the drive output element has been attached, other suitable measures must be applied to axially retain the rotor in place. For motors with a vertical type of construction with individual angularcontact ball bearings, then the rotor must be retained before the motor is brought into a horizontal position. Version issue January /22

5 Machine with rolling-contact bearing, without coupling Machine with rolling-contact bearing, with coupling Sleeve-bearing machine without coupling Sleeve-bearing machine with coupling Tightening torques of the central shaft nut of rotor braces and data on the pre-tensioning force for other types of rotor bracing devices and equipment Thread at the shaft end Tightening torque Pre-tensioning force M Nm 12 kn M Nm 20 kn M Nm 32 kn 1.2 Short-time storage If a motor isn t commissioned immediately, then it must be stored in a dry room or area that is free of any vibration. Details are, for example, provided in the corresponding Operating Manuals. 1.3 Long-time storage Motors that are to be stored for a longer period of time, must be stored in a dry, well ventilated room or area (the atmosphere must be free of any aggressive gases such as ammoniac, chlorine, sulfur etc.). This room or area must, as far as possible, be free of dust and vibration. The relative air Version issue January /22

6 humidity must be kept below 60% and the temperature approximately 10 C above the outside temperature. The motors must be well covered. If storage rooms or areas are not available with the characteristics specified above, then the motor must be completely wrapped in a polyethylene foil and the seams of this foil must be welded or glued so that they are absolutely airtight. Several bags of desiccant must also be placed in the polyethylene foil to absorb the water vapor that penetrates through the foil. The appropriate number of desiccant bags must be suspended within the airtight packaging and a humidity indicating device must be provided inside the sealed packaging. This device measures the humidity of the air in the packaging in four stages. The desiccant must be monitored and if required, replaced. For motors with condensation water drain holes, the plugs must be removed from time to time so that the condensation water - that has accumulated in the motor - can drain out. The shaft end has a special coating to protect it against corrosion. This protective coating must be checked at regular intervals and if required replaced. If the time between shipping the motor and commissioning it under favorable conditions (where the motor is stored in a dry room or area that is free of dust and vibration) for more than 3 years, or under unfavorable conditions for more than 18 months, the bearings must be replaced or relubricated. For motors with sleeve bearings, the oil reservoir of the sleeve bearing must be emptied. Open the bearings, remove the bearing shells, apply an anti-corrosion agent e.g. Tectyl 506 to the bare bearing components, bearing shells and bearing journals of the shaft and then re-assemble the bearings. Version issue January /22

7 2 Commissioning 2.1 Preparation After mounting or carrying-out service work, please check or ensure that: The motor was mounted and the operating conditions with the associated data match the data on the motor rating plate (voltages, currents, circuit configuration, type of construction, degree of protection, cooling etc.; also refer to the documentation supplied with the motor) As a result of the appropriately designed open-loop control and speed monitoring it is absolutely ensured that the motor cannot reach speeds that are higher than that stamped on the rating plate, The motor is correctly mounted and aligned The drive output elements, depending on their particular type have been correctly set and adjusted (e.g. belt tension for belt outputs; tooth edge and crest clearance for gearwheel output; aligning and balancing of couplings; radial play, axial guidance and the correct axial position for couplings of motors with sleeve bearings with two floating bearings) The minimum insulation resistances are maintained (this also applies after longer periods of time where the motor was not operational), refer to Point 1.4 The motor is connected corresponding to the specified direction of rotation The cooling air flow is correct and not restricted - and the warm air discharged from the motor (also from adjacent equipment) isn t directly drawn-in again, There is sufficient clearance between the cooling air input and wall/panel (e.g. 1/4 x diameter of the air intake opening) All retaining screws/bolts and connecting elements as well as electrical connections are correctly tightened, The grounding and potential bonding conductor connections are correctly established, Depending on the version, the bearings have been appropriately relubricated and have sufficient oil supply according to that stamped on the rating plate, For a newly installed motor that can be re-lubricated, or after a longer period when it was not operational, immediately after commissioning, the bearings must be re-lubricated at a minimum speed of n > 300 RPM If bearings are insulated, the insulation is not bypassed (the bearing insulation is stamped on the rating plate), Version issue January /22

8 NOTE: Possible additional equipment (temperature monitoring in the winding or bearings, anti-condensation heating etc.) have been correctly connected and are functional All protective measures against moving or live (under voltage) parts have been applied and if the second shaft end is unused, its keys are secured so that they cannot be flung out If a separately-driven fan is being used, this is ready to operate and is connected corresponding to the specified direction of rotation and when operational, does not have a negative impact on the smooth running characteristics of the motor If brakes are being used, then they must have been carefully checked to ensure that they are operating perfectly, If air-to-water cooling is being used (e.g. heat exchanger), the this must have been connected to a water supply, filled, vented and is ready for operation (this also applies after longer periods where the motor was not operational). This list cannot be complete and extensive. Additional tests and checks may be necessary according to the appropriate supplementary instructions, or may be necessary corresponding to the specific situation at the plant or system. 2.2 Power-on After motors have been mounted or service carried-out, we recommend that the following procedure is adhered to when commissioning motors: Start the motor without any load connected; to do this, close the circuitbreaker and after the motor starts, open the circuit-breaker again ( briefly start the motor and check the direction of rotation) As the motor coasts down, check for bearing noise and vibration and check the bearing end shields. When the motor runs perfectly from a mechanical perspective, powerup the motor again and accelerate it up the highest permissible speed (according to that stamped on the rating plate). If the motor runs roughly or omits abnormal noise, power-down the motor and as the motor coasts down, evaluate the cause of the problems. Version issue January /22

9 If, immediately after the motor is powered-down, the mechanical running characteristics improve, then the reason for the problem is either magnetic or electrical. If the mechanical running characteristics do not improve after the motor is powered-down, then the cause is mechanical: For example, the electric motor or driven load could be out of balance, the machine set (motor plus driven load) is not correctly aligned. If the motor runs perfectly smoothly, if cooling equipment is being used, then power it up now (separately-driven fan, water cooler etc.). Continue to monitor the motor for some time under-no load operating conditions. NOTE: Appropriately shorten the time for which the motor is powered-up if, for the preliminary test run, the separately-driven fan is still not to be operated. If the motor runs perfectly, connect the load to the motor. Check that the motor still continues to run smoothly and read-off and document the voltage, current, and power values. If at all possible, read-off and document the appropriate values for the driven load. Monitor the temperature of the bearings, windings etc. until steady-state values have been reached, document these values if possible, using the available test and measuring equipment. 2.3 Powering-down For motors, open the circuit-breaker and allow the motor to coast down unbraked. If a separately-driven fan and cooling system are being used and are not automatically controlled - then power them down and power-up the anticondensation heating. Version issue January /22

10 3 Maintenance Instructions for standard LV Motors 3.1 Safety instructions Before carrying-out any type of work on the motor (especially before opening covers on the active parts), carefully ensure that the motor and/or the plant is powered-down and disconnected from the line supply in compliance with the applicable regulations. The safety rules listed in the Operating Instructions should be especially carefully observed. In addition to the main circuits, it is also important that any supplementary or auxiliary circuits are also powered-down especially anti-condensation heating circuits! The usual 5 safety rules are as follows: Power-down and disconnect, Lock-out against accidental reclosure, Check and ensure that the system really is in a no-voltage condition, Ground and short-circuit (for voltage above 1000 V), Partition-off or cover adjacent, active parts and components. 3.2 Maintenance intervals Carry-out service & maintenance work carefully and at regular intervals Carry-out the appropriate inspections and audits in order to be able to identify possible faults and disturbances early on and resolve these before damage actually occurs. Adapt the service & maintenance intervals to the operating conditions and the local situation (pollution, power-on frequency, load, brush wear, insulation resistance). Carefully observe the re-lubrication intervals that are stamped on the rating plate. Version issue January /22

11 Overview of service & maintenance intervals Measures Intervals in operating hours At the latest after years a) First inspection After approx. 500 h ½ year b) Relubrication c) Cleaning d) Subsequent inspection Approx h to h depending on the bearings and operating type! 3 years Depending on the local degree of pollution and if brushes have to be replaced If favorable conditions prevail such as re-lubricating or grease change intervals e) Main inspection Approx. every h 2 years 3.3 Carrying-out an inspection When carrying-out any inspection work, all of the appropriate safety regulations must be carefully complied with. Only specialist personnel who have been adequately trained may carry-out inspection work. When operational, check that The specified technical data are maintained, for example Power drain, Temperatures (winding, environment, bearings, cooling air), No leaks occur (oil, grease or possibly water), Motor vibration levels remain below the highest permissible value (refer to 1.6), No abnormal bearing running noise can be heard (if required, carry-out an SPM measurement). When stationary, check that The foundation is free of depressions and cracks, The motor alignment lies within permissible tolerances, All of the mounting/retaining screws/bolts for mechanical as well as electrical connections are tight, The winding insulation resistance is adequately high (refer to 1.3), Version issue January /22

12 If insulated bearings are being used then the insulation is not bypassed (if insulated bearings are being used this is stamped on the rating plate), Cables and insulating parts, where accessible, are in an acceptable state and there are no signs of discoloring. Generally, when carrying-out standard inspections, it isn t necessary to disassemble motors. It only becomes necessary to disassemble the motor when cleaning it or when replacing the bearings. Version issue January /22

13 4 Checking the insulation resistance The insulation resistance is a measure for the insulating capability of the insulation of live (under voltage) parts and components with respect to ground and/or with respect to one another. If the insulating resistance is too low, then this can be due to poor implementation, damage, accumulated dirt or moisture condensation on the insulation. A voltage check may only be carried-out when the insulation resistance is adequately high. The safety rules according to EN (VDE 0105) - Operation of electrical plants and equipment and the appropriate Operating Instructions of the measuring and test equipment must be carefully observed when measuring the insulation value. 4.1 Preparation All of the external feeder cables must be disconnected before measuring the insulation resistance. If electronic components are installed and cannot be subject to the specified DC test voltage e.g. diodes, lightening/surge arresters and capacitors then these must be disconnected before the measurements are carried-out. If so specified they should also be shortcircuited. 4.2 Execution The DC test voltage must be connected between the live (under voltage) parts or components to be tested or with respect to ground. The DC test voltage should be connected long enough until the display practically no longer changes. For motors, depending on the size (power rating) and winding capacitance, this state can be achieved in between just a few seconds and up to one minute. The DC test voltage is 500 V DC. 4.3 Values Generally, the winding insulation resistances have a non-linear function with respect to the DC test voltage and the winding temperature. This is the reason that it should be carefully noted that reproducible results can only be achieved under precisely the same test conditions. Version issue January /22

14 Nominal values for minimum insulating resistances of reasonably new windings are listed in the following table. Generally, the actual insulation resistances are significantly higher. Rated voltage Minimum insulation resistance for a 500 V DC test voltage At 25 C At 75 C V N < 2 kv 10 MΩ 0.33 MΩ V N 2 kv 100 MΩ 3.33 MΩ Example: While the motor is operational, the winding insulation resistance can decrease as a result of environmental and operating effects. For a winding temperature of 25 C, the critical value of the insulation resistance is, depending on the rated voltage, obtained by multiplying the rated voltage in kv by the specific, critical resistance value of V N = 660 V 0.5 MΩ/kV at V N < 2 kv 5 MΩ/kV at V N > 2 kv R isol. > 0.66 kv x 0.5 MΩ/kV = 0.33 MΩ If the measured insulation resistance lies above the calculated (theoretical) critical value while operational, then the machine can continue to be operated. The minimum value of the insulation resistance R is is related to temperature. This is the reason that for different winding temperatures, it is necessary to convert the insulation resistance. For clean, dry (hardened) windings, the insulation resistance R is should be converted so that 10K temperature increase halves the insulation resistance R is and a 10K temperature decrease doubles the insulation resistance R is (10 C rule). Version issue January /22

15 Example 1: The measured winding insulation resistance on a winding temperature of 85 C is 0.1 MΩ. Referring to a winding temperature of 25 C, according to the 10 C rule, this corresponds to a value of 6.4 MΩ (see table) 0,1 MΩ 0,2 MΩ 0,4 MΩ 0,8 MΩ 1,6 MΩ 3,2 MΩ 6,4 MΩ 85 C 75 C 65 C 55 C 45 C 35 C 25 C Example 2: The measured winding insulation resistance on a winding temperature of 10 C is 200 MΩ. Referring to a winding temperature of 25 C, according to the 10 C rule, this corresponds to a value of 200 MΩ (see table) 200 MΩ 100 MΩ 75 MΩ 10 C 20 C 25 C Minimum insulating resistances for parts that are integrated in the motor or mounted on the motor: Temperature sensor: 500 MΩ Anti-condensation heating 1 MΩ Other accessories: 100 MΩ Insulated bearings 1 MΩ (100 V DC test voltage) Version issue January /22

16 Instructions and measures when storing the motors for longer periods of time - as well as commissioning and maintenance of low voltage motors 5 Greases and regreasing 5.1 Grease designations according to DIN and Example: DIN K 3N Li Grease DIN K 3 N - Li Acc.to DIN ; Tl.1 K Basic mineral-based oil (if other supplementary code letters are missing) Acc.to DIN , Tl. 2 KTC Lower operating temperature, 50 C Acc. to DIN L Active substance to increase protection against corrosion and/or aging. Renowned, international manufacturers guarantee this quality also without using this code letter E Basic synthetic oil, E = Ester oil, deviating from code letter K (basic mineralbased oil) 2 (3) Consistency code and worked penetration, classified acc. to the NLGI Class (a lower number corresponds to a softer) grease Version issue January /22

17 Instructions and measures when storing the motors for longer periods of time - as well as commissioning and maintenance of low voltage motors Operating temperature and resistance to water Acc. to DIN ; Tl.1 K C Acc. to DIN ; Tl.1 N C Acc. to DIN ; Tl.1 P C Acc. to DIN ; Tl.2 G C Acc. to DIN ; Tl.2 K C Li L - lithium grease as thickening agent - microgel or gel - anorganic thickening agent - lower operating temperature, e.g. 30L = -30 C As a result of the selected re-lubricating intervals, the permissible upper temperature at which the grease is used should be a minimum of 20 K above the bearing operating temperature. Version issue January /22

18 5.2 Lubrication and relubrication intervals For motors that can be re-lubricated (i.e. they have regreasing equipment), as a result of defined re-lubrication intervals, the bearing lifetime can be extended and/or unfavorable influencing factors such as temperature, the effects of mounting, speed, bearing size and mechanical load/stress can be compensated. From shaft height 280 and upwards, bearings can be relubricated using a flat lubricating nipple M10 x 1 according to DIN Bearings can be relubricated using an optional nipple for shaft heights 100 to 250 (K40). Motors with bearings that can be relubricated always have a lubrication instruction plate. This has information about the lubricating grease type, the regreasing interval and quantity of grease required for each lubrication point. The specified grease change intervals apply for operation under normal load conditions, operation at speeds that correspond to those stamped on the rating plate, low-vibration operation, essentially neutral ambient air and the use of high-quality rolling bearing grease specified on the re-lubrication instruction plate (original lubrication). K3N-Li or K3P-Li greases are to grease bearings of standard motors for the first time: Version issue January /22

19 Motors 1LA6, 1LA8 K3N-Li Grease SHELL Alvania RL3 (old G3) Comment: The manufacturer has replaced Shell Alvania G3 by Shell Alvania RL3. Caution: K3N greases ARAL / Aralub 4340 DEA / Glissando 30 ESSO / Beacon 3 Fuchs / Renolit FWA 220 SHELL / Alvania RL3 (old G3) SHELL / Alvania R 3 WINTERSHALL / Wiolub LFK 3 K3P grease Only use suitable and tested, high-quality roller bearing greases to re-lubricate bearings. Only re-lubricate the bearings when the motor has a speed of at least n > 300 RPM. These greases have lithium soap as thickening agent and mineral-based oil as basic oil. When using other K3N greases that may only comply with the minimum requirements according to DIN then the lubricating intervals must be halved. Greases may never be mixed with different thickening agents and basic oils! Motors 1LG4/6,1LA5/7/9 - K3P-Li grease ESSO UNIREX N3 K3P grease ESSO UNIREX N3 Grease lifetimes and relubrication intervals are only valid in conjunction with this grease type. Other greases must, as a minimum, comply with DIN KL3N (refer to the Table above). In this case, the lubricating intervals for KT >25 C should be reduced. Only relubricate bearings when the motor has a speed of at least n > 300 RPM. Special greases Special greases are specified on the lubrication instruction plate. For instance, Klueberquiet BQH is used for high-speed motors that are fed from drive converters. This is grease with synthetic oil base that cannot be mixed with standard greases (mineral oil). Version issue January /22

20 Regreasing intervals for Standard catalog-motors This table is form information purposes only. The precise re-lubrication intervals should be taken from the motor re-lubrication plate. Grease life and relubrication intervals Permanent lubrication Grease life up to CT 40 C 1) Type Series Frame Size Number of poles All 56 bis bis h or h 2) Regreasing 1) Type Series Frame Size Number of poles Regreasing interval CT 40 C 1) 1LA6 100 to to h 180 to h 4 to h 280 to h 4 to h 1LA5 100 to to h 1LA7 1LA9 1LA8 315 to h 4 to h h 4 to h 1MA6 100 to to h 225 to h 4 to h h 4 to h 1MA7 100 to to h 1MJ6 180 to to h 1MJ7 225 to h 1MJ8 4 to h 1MJ h 4 to h 355 to and h 6 and h 1LG4 180 to h 1LG6 4 to h h 4 to h 1) 2) If the coolant temperature is increased by 10K, the grease life and regreasing interval are halved h applies to horizontally mounted motors for coupling abrasion (wear) without additional axial loads. Version issue January /22

21 6 Vibration 6.1 Vibration severity When evaluating the general vibration condition of electric motors the RMS vibration velocity is generally measured [mm/s] (frequency bandwidth between 10 Hz and 1000 Hz); this technique is generally sufficient. 3 1 The limit values for the measured vibration severity values are defined by ISO depending on several machine classes. A B C D recently commisioned operation unlimited long time operation short-time operation vibration that causes damage The vibration condition is evaluated in four stages. mm/s inch/s 11 0,44 7,1 0,28 4,5 0,18 3,5 0,11 2,8 0,07 2,3 0,04 1,4 0,03 0,71 0,02 Vibration velocity Hz n > 600 RPM ( Hz n > 120 RPM Rigid flexible Rigid flexible Rigid flexible Rigid flexible Foundation medium-sized big machines Pumps > 15 kw machines 300 kw < P < 50 radial, axial, diagonal 15 kw < P 300 kw MW Motors Inter-shaft / Motors direct drive 160mm H < belt drive 315 H 315mm group 4 group 3 group 2 group 1 Group Machine type Version issue January /22

22 7 Apendix 7.1 Internet links This list is by no means complete and only provides a selection of appropriate sources. Topic Title \1\ Service & Support Siemens A&D Customer Support \2\ 7.2 History Tabelle 7-1 History Version Date Changes V1.0 January 2008 First issue Version issue January /22