【 Weak current College 】 elevator maintenance experience with frequency converter

A Mitsubishi A540-55K converter, this machine could have broken a module, for good measure, to the rear drive is functioning, the trigger line dial-out module, resulting in a power check on the trip, found and burned a module IGBT module so the trigger-line dial triggered off may have a small amount of voltage, this module is half powerup on-State, a short-circuit Burnout as a result, this characteristic GTR module to this test!

Many Mitsubishi A240-22K converter, all bad module! because maintenance is not good, such as radiator dust multiple plug, circuit board is too dirty, thermal grease failure, etc., this inverter output module (PM100CSM120) is an integration module, is bad all the way to the entire change, maintenance of high prices! good module also hard to find! if you haven't broken the inverter, you have to careful maintenance!

A Yaskawa 616G5-55KW inverter, badly damaged and it turned out to be a fast fuse (three-phase has a fast penetration), electrician may have no experience, no checking module of the problem, but also unable to find fast melting, replaced by a copper wire, turn on after a loud crack, two modules, the absorbing circuit, driving Board is unable to repair, replacement plate, resulting in substantial losses if the module is mostly fast fuse, but bad fast melting does not necessarily replace broken! copper melting faster had seen many times!

Often someone in the Mitsubishi A240-5.5KW inverter when exchanging A540-5.5KW A540-5.5KW "N" line earthing! a transmission frequency converter is gives bang!-converter damaged!, on the one hand the "N" A540-5.5KW line and A240-5.5KW inverter ground position similar to the electrician didn't! clear grafted in the ground; some are mistaken for electricians "N" line is ground! please Mitsubishi inverter users be careful wiring!

Appearance like how to detect the current module, is actually very simple, just use the capacitance meter, detect module C-E G-E or electrical capacity, the current capacity is big! attention to similar modules in comparison!

Try to Converter output voltage converter you find over 1000 volt (enter 380V), asked whether there is a frequency inverter fault? burn motor? he also did not understand the converter will only boost buck, not the original he is!! digital multimeter measurement, because the converter output voltage is high-frequency carrier, no anti-jamming measure digital table here is very inaccurate!
In the Mitsubishi A540 auxiliary power inverter (R1, T1) wiring is not off the shorted tablets, results in the inverter burned after also could not understand his reasons, the original when shorted tablets didn't take off, the inverter internal R and R1, T and T1 is already linked, the electrician thought from R, T has two lines, the result put T R received the S1, R1, white received short circuit, R1, R and T and T1 line is via power plate's middle tier, as a result the power Board burn burst open into two layers! in general there is no need to add auxiliary power supply (R1, T1)!

When the maintenance frequency converter does not know how to use fake load, when the driver is at fault, burned the module after said module quality! false load is one of several hundred European resistance (light gun can), conspiracy in the main loop, such as a fast melting put it away, loading resistance; no fast melting in the main back to anywhere on this disconnect, conspiracy! this resistance to current limiting resistor, when the module is short-circuit will not burn down the modules, etc. after powering the normal measurement transducer output, before this fake load pulling!!
Many factories-powered generator is, when generating a fault, the output voltage often converter and electronic instrumentation burned! there's one last year for Shenzhen home-drawing factory once broke down over Taiwan 30KW inverter, cut off 10 days, causing heavy losses, the factory in generator made many protection method may not be obvious! a later we want passive protection methods, Inverter or instrument input air switch plus a varistor (380V, with 821K 220V471K) so when a high-voltage, pressure-sensitive will short circuit, air switch tripping, protection of the frequency converter, inverter fault rate is significantly reduced, varistor is cheap, this method is to spend money doing big things!

Parallel (three-phase is a Delta connection) of varistor wattage sizes not strictly required, enter the current of the selection of varistor relatively little (or a few parallel)! when varistor unlit when it is completely short-circuit! now also requires that you have good quality of air switch, responsive! protection current and not too large!, of course, is received by the local air switch output!

Speaking of varistor, a converter which input also varistor, should also have guaranteed! minor injuries by just blowing circuit board of copper wire, serious injury to burn the rectifier module, switch power supply, CPU board, capacitors, causing serious injuries may be when a varistor short circuit when its metal debris flying everywhere; explosion issue strong electrostatic and electromagnetic waves (very much like lightning strike); blow Board of copper wire make air switch not actions. Therefore, in the converter outside the other pressure sensitive resistor is much better!



Some people buy the module requires model a verbatim! actually completely unnecessary, as the module parameters with 7MBR25NE-120 7MBR25NF-120 is the same, only more of the four positioning feet! because IGBT module driver is voltage control, better interchangeability, as long as the voltage, the current parameter, a different model IGBT modules are interchangeable! have sizes of installation can also be another boring! GTR module you will also need to consider its magnification, interchangeability narrowly! we repair the inverter so cheap it is to take full advantage of the module interchangeability, avoid using the module on the market, sell, otherwise the module price high or hard to find!

How to choose a module: Maintenance frequency converter, judging the quality of the module is key! first you want to see the module is opened too (see appearance marks), and now has many modules are maintenance, parameter correctly but the quality is very poor! pressure value is the most important parameter, the available voltage 380V, enter the measurement of inverter output module voltage value is greater than 1000V, 220V, 600V! current available capacitor comparison table to determine the size! IGBT module can also be used analog multimeter 10K stall detection if it is capable of action, use the pointer (black-red) to trigger module G-E enables module C-E breakover, when G-E shorted, C-E close! this method is the simplest and most basic measurement method, is the maintenance of the novice to the professional may not measure!

Screw did not tighten! look like, but on the inverter is deadly! there are a lot of inverter when mounted on a vibration device (such as industrial washing machines, machine tools, etc.) to run for a period of time, its main circuit connection screws and tighten the screws of the module is easy to loose, in which the first damage is usually a module, if the module has no other screw-fastened, the module will soon broke down, complained that the module quality! also placed special emphasis on not to inverter mounted on vibration device, otherwise good converter may soon broke!

Often see maintenance frequency converter not fake the results of a load, or burning module can load with fake!, almost can be forearmed! unless you buy are counterfeit module!!

Fuji G9-5.5KW inverter rectifier module CVM40CD120 structure Description:

Rectifier parts: R, S, T, A (+) and N-(-)

Charging SCR: A, P1, Gth (trigger)

Brake pipe: DB, N-, G7 (trigger); DB, B + is its continued flow diode

Power switching valve: D8, S8, G8

Th1, Th2 thermistor:

Mountain Ken MF series has a common failing is sometimes displayed "Erc" failure, then you can do the following: open the parameters, write "90", in which case the inverter 7831 show "PASS", write "number" converter capacity, then the value parameter to restore factory (parameter 36 = 1)!

Inverter capacity: 2.2KW-233.7KW-247.5KW-26

15KW-2822KW-3030KW-31

45KW-3375KW-35110KW-37

Other power and so on!

On the elevator inverters daily maintenance: now the elevator are frequency converter to control when the converter failed will give many people the inconvenience, but also sharp bad managers, if you usually have to inverter for maintenance, you can significantly reduce the frequency of failure rate, we maintain a large number of elevator inverters, summing up the usual maintenance of several issues to note:

1) elevator electric apparatus room temperature must not be too high, or the converter component is easy to aging, air-conditioned, the effect is pretty good!

2) prevent the rain soaked, usually on the scraping of Typhoon, Windows blown out the inverter from the rain.

3) lightning, this is the entire building or lightning protection throughout the community, being struck by lightning on facilities of inverter General badly damaged.

4) converter cooling fans to scheduled cleaning dust, found that there is sound or not functioning to be replaced.

5) Elevator motor abnormal noise is usually a problem, such as inverter motor three-phase current unbalance, then it is best to repair, wait until the inverter full occurs, you may be seriously damaged. If you do not have maintenance experience don't own maintenance, many people get worse converter.