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CleanEffects AccuClean Service and Repair
CleanEffects AccuClean Service and Repair

Intro_to_Motors Workshop
Intro_to_Motors Workshop

GS2613561363
GS2613561363

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... mechanisms and lifting devices also require consideration for drop prevention. ...
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE) e-ISSN: 2278-1676,p-ISSN: 2320-3331,
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE) e-ISSN: 2278-1676,p-ISSN: 2320-3331,

... As of now, various research works have been tried in the section of PQ maintenance and enhancement. Some devices such as DVR, UPS and many others are used for maintaining the quality power supply. But, these devices are capable of maintaining only the symmetrical or unsymmetrical power supplies, so ...
Ahmad Shtaiyat
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... have all of the control circuitry built in and are easy to control; they have 3 wires which represent signal, Voltage, and ground. By pulsing the signal line you can go forward, stop, or backward. ) , or Gear motors ( Gear motors will require additional control circuitry (normally an H-bridge) to al ...
Crown FM4000 Manual
Crown FM4000 Manual

... in FM transmitter design offering modularity, ease of use, and long-term reliability. The FM4000 package includes two (2) PA2000 amplifiers, two (2) PS2000 power supplies, a combiner with coupler, a transmitter controller, and all necessary cabling. The PA4000 transmitter package requires no tuning ...
EMI EMISSIONS
EMI EMISSIONS

... Insulated Gate Bipolar Transistors (IGBT) semiconductors with rise/fall times trise < 200 ns and are inherent sources of radiated and conducted EMI. Pulse repetition rate is called carrier frequency (fc) and for IGBT ASDs is user selectable with fc = 1-2 kHz on high hp drives and fc over 12 kHz poss ...
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single-phase bridge rectifiers with current filters

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LT1571

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... motor load from the last test indicates a change in the driven load, the cause of which should be understood. Lubricating appropriately. Manufacturers generally give recommendations for how and when to lubricate their motors. Inadequate lubrication can cause problems, as noted above. Over-lubricatio ...
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... transmission and distribution and also requires greater generation and distribution capacity. The various items in a transmission and distribution system have some resistance and this produces a loss when current flows. The amount of loss is proportional to the square of current and is associated wi ...
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955 Brik Series Linear Position Sensor

... over the entire active stroke length of the LDT. The unit can easily be changed in the field from a 0 to 10VDC to a 10 to 0VDC or 4 to 20mA to a 20 to 4mA. Keep in mind that there is a 2.75” Null area at the connector end of the LDT and a 2.75” Dead band at the other end of the LDT that the magnet m ...
SN65LBC182 数据资料 dataSheet 下载
SN65LBC182 数据资料 dataSheet 下载

... unit load allowing connection of up to 128 similar devices on the bus. The high ESD tolerance protects the device for cabled connections. (For an even higher level of protection, see the SN65/75LBC184, literature number SLLS236.) The differential driver design incorporates slew-rate-controlled outpu ...
ADL5315 数据手册DataSheet 下载
ADL5315 数据手册DataSheet 下载

34-MS-001-Kit Schnitz Micro Storm Nitrous Controller
34-MS-001-Kit Schnitz Micro Storm Nitrous Controller

Aalborg Universitet Wang, Xiongfei; Blaabjerg, Frede; Loh, Poh Chiang; Pang, Ying
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... 2) Super-synchronous resonances: These resonances above the fundamental frequency can be triggered by grid background harmonics, which are mainly low-order (5th and 7th) [4]-[6], or caused by the interactions among current control loops of grid converters, which is typically in a high-frequency rang ...
CONTROLLED POWER COMPANY
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... others including UNIX and ZENIX operating systems. 7.2.2 Full duplex ASCII, RS/232 Serial Port. This port provides over 60 operating, diagnostic and performance characteristics. ...
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A Series-LC-Filtered Active Damper for AC - VBN

... 2) Super-synchronous resonances: These resonances above the fundamental frequency can be triggered by grid background harmonics, which are mainly low-order (5th and 7th) [4]-[6], or caused by the interactions among current control loops of grid converters, which is typically in a high-frequency rang ...
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... Mode Selection. When this pin is HIGH and the IMPULSE pin is LOW, this input selects the fastest mode, the maximum throughput is achievable, and a minimum conversion rate must be applied in order to guarantee full specified accuracy. When LOW, full accuracy is maintained independent of the minimum c ...
sample specification- apss
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... The APS shall be equipped with a front-mounted LCD display indicating the selected output current step; if the APS is switched off; or if the APS is in Remote Control. The LCD display shall also indicate the APS output voltage. The APS shall also be equipped with a front-mounted input-power circuit ...
PCM1727 数据资料 dataSheet 下载
PCM1727 数据资料 dataSheet 下载

... a 27MHz master clock or crystal oscillator and generate all internal system clocks required to operate the digital filter and ∆Σ modulator, at 384fS. If an external master clock is used, XT2 must be connected to ground. In both cases, the signal amplitude on XT1 must satisfy the specification descri ...
New Method for Comparison of Chopped Waveforms in Impulse
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... have different chopping times, due to the arc generation process between the rods. Moreover, as reduced and full level tests have large difference in the peak voltage, it is very difficult to adjust the rods in order to maintain the same chopping time. A better and more stable device is a sphere gap ...
LM1894 数据资料 dataSheet 下载
LM1894 数据资料 dataSheet 下载

... volume controls as shown in Figure 1. This is because any adjustment of these controls would alter the noise floor seen by the DNR control path. The sensitivity resistors R1 and R2 may need to be switched with the input selector, depending on the noise floors of different sources, i.e., tape, FM, ph ...
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Pulse-width modulation



Pulse-width modulation (PWM), or pulse-duration modulation (PDM), is a modulation technique used to encode a message into a pulsing signal. Although this modulation technique can be used to encode information for transmission, its main use is to allow the control of the power supplied to electrical devices, especially to inertial loads such as motors. In addition, PWM is one of the two principal algorithms used in photovoltaic solar battery chargers, the other being MPPT.The average value of voltage (and current) fed to the load is controlled by turning the switch between supply and load on and off at a fast rate. The longer the switch is on compared to the off periods, the higher the total power supplied to the load.The PWM switching frequency has to be much higher than what would affect the load (the device that uses the power), which is to say that the resultant waveform perceived by the load must be as smooth as possible. Typically switching has to be done several times a minute in an electric stove, 120 Hz in a lamp dimmer, from few kilohertz (kHz) to tens of kHz for a motor drive and well into the tens or hundreds of kHz in audio amplifiers and computer power supplies.The term duty cycle describes the proportion of 'on' time to the regular interval or 'period' of time; a low duty cycle corresponds to low power, because the power is off for most of the time. Duty cycle is expressed in percent, 100% being fully on.The main advantage of PWM is that power loss in the switching devices is very low. When a switch is off there is practically no current, and when it is on and power is being transferred to the load, there is almost no voltage drop across the switch. Power loss, being the product of voltage and current, is thus in both cases close to zero. PWM also works well with digital controls, which, because of their on/off nature, can easily set the needed duty cycle.PWM has also been used in certain communication systems where its duty cycle has been used to convey information over a communications channel.
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