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電機(jī)運(yùn)行電磁噪音增加。變頻器輸出的是矩形波電壓，存在高頻分量，因此電機(jī)會產(chǎn)生刺耳的高頻噪音，該噪音明顯大于風(fēng)機(jī)的噪音，給噪音測量帶來了難題。
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(3)電機(jī)溫升升高。變頻器輸出電壓波形不是正弦波，而是畸形波，在額定扭矩下的電機(jī)電流比工頻時(shí)要多出約10%左右，所以溫升比工頻時(shí)略有提高(低次電流諧波使銅損增大，高次諧波使鐵損增大)，給電機(jī)溫升試驗(yàn)帶來不便，使得溫升試驗(yàn)結(jié)果偏差較大。
(4)普通電磁、數(shù)字測試儀表失靈。變頻器的輸入電流和輸出電流中都有頻率較高的高次諧波成分，高次諧波電流所產(chǎn)生的電磁場具有輻射能力，使其他設(shè)備(尤其是通信設(shè)備)因接收到電磁波信號而受到干擾，使得電磁式儀表、數(shù)字式儀表都不能用來直接測量交流電壓和電流，必須采用整流式儀表才能進(jìn)行較為準(zhǔn)確的測量。
變頻器是可以改變頻率和電壓的電源。變頻器是由交流-直流-交流(調(diào)制波)等電路構(gòu)成的，將電網(wǎng)三相交流電經(jīng)過三相橋式整流成脈動(dòng)直流，再通過電解電容和電感濾波成平滑直流，*后通過逆變器，逆變成電壓和頻率可調(diào)的三相交流電。變頻器標(biāo)準(zhǔn)叫法為變頻調(diào)速器。
變頻器的輸入電路是三相交流電源經(jīng)全波整流后向?yàn)V波電容器充電的電路，輸入電流總是出現(xiàn)在電壓的振幅值附近，呈不連續(xù)的沖擊波形式，如圖2所示，變頻器的輸出電路是把直流變成頻率連續(xù)可調(diào)的三相調(diào)制交流電壓的逆變橋電路，其輸出電壓波形是正弦調(diào)制spwm波，如圖3所示。
Olympus HMTV-1 X1.5 C-Mount Lens
Justrite 10208 Plunger Can, 2 QT CAP(US) / 1.9 Liters
Honeywell CR71B1054 Four Stage Chiller, 120V, 60Hz
Melles Griot 59 LGF 412-S Lens
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New Box of 6 CART-GAC20-IND-SHR 155111-03 Granular Activated Carbon Filter
Olympus H100-012-090 HMTV-1 Probe
Mitutoyo 378-801 M Plan Apo 2 Lens (for parts)
Olympus PE 3.3X 125 Microscope Photo Eyepiece 27mm x 51mm Overall
Flanders Pureform 0-007-F-02-03 HEPA Filter 1000CFM 24" x 24" x 11.75"Thick
Combustion Engineering Fulscope ER/C Circular Chart Recorder 120/240V 50/60Hz
Electrothermal CM1000C Heating Mantle 110/120V 50/60Hz, 300W, 450C Max
R&D BOX OVEN 36" x 36" x 22.5" 120V
JPSA Mask Mount Block Adjustable 2-Axis 6.5mm Range 1 3/4" Aperture
JPSA A00014-MIC Focus Lens Mount 3-Axis Control 1 1/2" Aperture Diameter
JPSA A00560 Homogenizer Lens in Mount 1/2" x 1" 2" ID Mount
Opto Sigma 014-1400 Fused Silica liano Convex Lens with Mount 500mm Focal Length
JPSA UVM-2-.375-248HR45 Turning Mirror 90° 2-Axis Adjustable 1 3/4" Diameter
SPX / Blue M Oven Door 29 3/4" x 42 3/4" x 4 1/2" Thick 3 Latch 1 Handle 3 Hinge
Vented Enclosure Attached to Workbench 41" x 28" x 16 3/4" Enclosure 3/4" Thick
Parker LT10V Single Filter Cartridge Vessel 3" Inner Diameter 10" Depth 3/4" NPT
Filter Housing 3" Inner Diameter, 10" Depth 3/4" NPT Outlet/Inlet w/Metal Filter
Filter Housing 5-1/4" Inner Diameter, 10-1/4" Depth, 1" NPT Outlet/Inlet
Filter Housing 3" Inner Diameter, 9" Depth, 1/2" NPT Outlet/Inlet
Filter Housing 3-1/2" Inner Diameter, 9" Depth, 3/4" NPT Outlet/Inlet
Associated Environmental Systems SD601SLC Environmental Chamber w/AES 86648
Winthrop Pharmaceuticals 712214 Contrast Media Warmer *For Parts, Not Working*
Drucker 853VES Fisher Heal Horizon Plasmafuge-12 *For Parts, Not Working*
Lab-Line 4682 Digital Reciprocating Water Bath Shaker, 120VAC, 11.66A, 1400W
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330106-05-30-10-02-05
330130-040-00-00
330130-040-01-00
330130-045-00-00
9563-810
9853-610
DSAI110 57120001-DP
M3575R-H33BF
M68CPU CPU
MC-4/11/01/400
S-D4006-D
S-D4006-D S-D4006
S-D4008-A S-D4008
SM 25/50-TCT DC 560V 25A 06231-103
SR 469 469-P5-HI-A20
1336F-BRF200-AN-EN
1336F-BRF200-AN-EN
BS206 BIO420 BIO420/00
BS204 BIO246 BIO246/00
BS205 BIO413 BIO413/00
1336-BDB-SP6A
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Techniquip TLC-5 Fluorescent Ring Light 120V
Nikon 10x/21 10x Microscope Eyepiece (light scratches on lens)
Nikon 10x/21 10x Microscope Eyepiece
Aerotech A0M105-2 Gimbal Optical Mount for 2" Dielectric Lens
Aerotech A0M105-2 Gimbal Optical Mount with 2" Dielectric Lens
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