YASKAWA JANCD-MM13B 电气参数里总结说RS-485电气驱动能力，在多点网络拓扑结构下，可驱动32个站点。那么怎么去解读这一指标呢？ 首先来考察一个站点收发电路特性，收发器的接收电路其标准等效输入阻抗为12kΩ,比如MAX 485数据手册为例：
至于为什么是32个呢？主要是由于前面200mV最小驱动能力的规定。 也可以这样理解一下，每一个接收电路输入阻抗并非理想的高阻，而是12kΩ，那么比如其中一个站点发送，就相当于有32个站点的输入阻抗并联，为什么是32个呢？别忘了发送站点自身也有接收电路，所以在不考虑端接电阻以及线路阻抗的情况下，对于发送电路接了一个等效负载：，而发送电路驱动能力肯定是有限的，这样就好理解了。 下面这个图就是所谓的多点网络拓扑，所有的站点都是沿着双绞线的排布并接在总线上的。
所以，你有可能会在一些地方看到所谓的一个单位RS-485负载的说法，这里所谓的单位负载就是指12kΩ标准输入阻抗，这个12kΩ就是EIA-485标准定义的。从而看到比如单位负载之类的说法，就是源于此处。
数据监控
比如一个基于RS-485的Modbus-RTU多点网络中，在做协议编程或者实际多站点总线调试的时候，有可能需要监控总线上所有的报文。甚至还有可能就像实现一个总线报文的的记录器，将总线上所有的报文都记录下来。应该怎么实现呢？ 买一根USB转RS-485的转换线或者自己做一个也可以。将A/B线并接在总线上，USB 插入电脑。使用串口监控终端或者自己写一个串口接收小软件，就可以监控所有总线上的报文了。 比如这个AccessPort串口工具就比较好用：
应用设计
作为应用设计而言，需要考虑这些维度：
端接设计
隔离设计
端接设计
首先为什么要端接？这是由于RS-485采用双绞线传输，标准规定的双绞线的差分特征阻抗在100Ω至150Ω之间。RS-485标准制定者选择120Ω作为标称特征阻抗。
YASKAWA JANCD-MM13B
ABB YB560103-CB DSQC236B DriveUnit
ABB YB560103-CC DSQC236C DriveUnit
ABB 3HAB2207-1 DSQC236D DriveUnit
ABB YB560103-CD DSQC236G DriveUnit
ABB 3HAB2207-1 DSQC236P DriveUnit
ABB YB560103-CE DSQC236T DriveUnit
ABB YB560 103-CL/5 DSQC241 PowerUnit
ABB 3HAB 2210-1 DSQC300 Robot Computer
ABB 3HAB 2216-1 DSQC314B PowerUnit
ABB 3HAB 2219-1 DSQC316 Main Computer
ABB 3HAB 2220-1 DSQC317 6MB Card
ABB 3HAB 2236-1 DSQC321 4MB Card
ABB 3HAB 5956-1 DSQC323 8MB Card
ABB 3HAB 5957-1 DSQC324 16MB Card
ABB 3HAB 2241-1 DSQC325 Main Computer
ABB 3HAB 2242-1 DSQC326 Robot Computer
ABB 3HAB7229-1 DSQC328 I/O Card
ABB 3HAB 6182-1 DSQC335 Robot Computer
ABB 3HAB8101-3/05D DSQC345B DriveUnit
ABB 3HAB8101-3/08C DSQC345C DriveUnit
ABB 3HAB8101-7/01C DSQC346C DriveUnit
ABB 3HAB8101-8 DSQC346G DriveUnit
ABB cable DSQC351 Interbus-S
ABB 3HAC 0373-1 DSQC361 Main Computer
ABB 3HAC3180-1 DSQC373 Robot Computer
ABB 900054 1Gb SD-card S3/S4 DDR
ABB 900056 1Gb SD-card S2 DDR
3HNE 00026 Teach Pendant
3HNE 00312-1 Teach Pendant
3HNE 00313 Teach Pendant
CHAA 3560-AXA Teach Pendant
ABB 3HAB9271-1/01B DriveUnit Dummy DriveUnit Dummy
ABB 57510001-AA DSCA 114 Print out board
ABB 57520001-U DSCA 121 Communication board
ABB 57160001-A DSDI 110 Digital b board
ABB 57160001-K DSDO 110 Digital output board
ABB YB161102-AH DSDX 110 Digital in/output board
ABB 57160001-TP DSDX B001 digital in-output board
ABB 57360001-U DSMB 124 Semiconductor memory board
ABB 57360001-AN DSMB 125 Semiconductor memory board
ABB 57360001-HG DSMB 127 Memory board
ABB 57330001-N DSMC 110 Floppy disk controller
ABB YB161102-AK DSPA 110 Axis computer
ABB 57310256-AF DSPC 150 Central processor
ABB 57310256-BA DSPC 153 Expand. single board computer
ABB 57310001-GP DSPC 157 Expand. single board computer
ABB YB161102-AD DSQC 103 Resolver power board
ABB YB161102-AF DSQC 105 Display board
ABB YB161102-BA DSQC 110 Programming board
ABB YB161102-BS DSQC 115 Resolver power board + 2 analogue
ABB YB161102-BE DSQC 116 Power supply
ABB YB161102-BG DSQC 117 Resolver power board
ABB YB161102-BU DSQC 124 Terminal unit
1B30023H01 2
1B30023H02 2
1B30035H01 2
1C31116G04 8
1C31122G01 2
1C31125G02 2
1C31129G03 9
1C31132G01 9
1C31147G01 0
1C31166G01 2
1C31169G02 1
1C31194G01 1
1C31197G01 1
1C31219G01 5
1C31222G01 2
1C31223G01 4
1C31224G01 15
1C31227G01 30
1C31232G03 2
1C31233G01 3
1C31234G01 15
1C31238H01 9
1D54561G02 5
1D54582G02 3
1D54582G05 3
1X00024H01 4
1X00163H01 2
1X00185H01 5
2380C91G03 30
249-06-02 5
249-06-04 12
2840A18G01 20
2840A18G02 20
2840A18G03 40
2840A18G04 40
2840A19G06 2
2840A19G07 2
2840A20G01 40
2840A20G02 40
2840A20G03 40
2840A21G01 30
2840A21G02 30
2840A21G04 10
2840A38G01 10
2840A49G01 / 404A724G01 QEX QEX Q-Line Extender 5
2840A78G01 5
2840A79G01 20
2840A80G04 4
2D34347G06 10
2D34347G08 5
3A58939G15 10
3A98826H01 10
3A99116G01 20
3A99132G01 5
3A99132G02 5
3A99158G01 5
3A99229G01 2
3A99537G01 10
3A99661H01 20
3A99695H01 30
405A379H02 20
405A431G01 5
405A616H01 5
405A662G01 30
405A662G02 30
405A689G03 5
405A689G04 5
405A832H01
405A893G01 3
405A893H01 3
406A036H01 30
4256A01G01 / 772B450G01 5
4256A10G01 60
4256A25G01 / 1C31025G03 7
4256A25G01 / 1C31025G03 1
4256A26G01 2
4256A41G01 1
4256A41G01 1
4256A64G02 / G50 10
4256A64G05 18
4256A65G02 100
4256A65G05 100
4256A66G01 11
4256A67G01 3MBPS13 P/S Board 18
4256A84G03 / 3A99159G03 3
4256A88G04 40
4256A90G01 10
4256A90G02 5
4256A91G01 10
4256A91G02 5
4256A91G03 10
4256A93G01 5
4256A94G01 5
4256A96G01 5
4256A96G02 5
4256A97G01 10
4256A98G01 5
4256A99G02 8
4626B58G03 2
4620B91G01 2
4A00081G01 2
4A00081H01 2
4D33613G01 2
4D33613G02 2
4D33644G02 2
4D33644G04 2
4D33644G06 2
4D33645G05 1
4D33743G01 5
4D33755G01 45
4D33755G04 2
4D33811G01 10
4D33811G02 10
4D33865G01 5
4D33865G02 5
4D33865G03 5
4D33913G01 3
4D33913G02 3
4D33916G01 5
5A23307H15 5
5A26391H03 2
5A26433H01 8
5A26434H01 3
5A26457G01 4
5A26458G01 4
5D32123G02 5
5D32191G01 20
5X00058G01 1
5X00059G01 1
5X00070G04 10
5X00105G07 1
5X00105G14 1
5X00117H03 10
5X00119G01 3
5X00121G01 2
7379A06G02 50
7379A21G01 20
7379A21G02 / 3A99164G02 / 3A99164G50 20
7379A29G01 10
7379A31G01 5
7379A31G02 / 3A99165G02 20
7379A31G03 / 3A99165G03 / 3A99165G50 10
7379A31G04 30
7379A31G05 5
7379A62G01 20
7379A62G02 30
7379A84G01 30
7379A89G01 1
7379A92G02 1
7379A92G02 13
7379A92G03 71
7379A93G01 4
7380A29G03 3
7380A36G01 50
7380A37G02 10
7380A43G01 10
7380A51G01 10
7380A70G02 39
7380A72G01 5
7380A78G01 15
7380A84H01 3
7380A92G02 50
7380A92G03 50
7380A92G04 50
7381A01G01 / 772B388G01 10
7381A01G02 / 773B388G21 10
7381A01G03 MSP 10
7381A01G04 / 772B388G51 10
7381A08G01 / 772B400G04 10
7381A10G03 50
7381A28G02 10
7381A29G01 8
7381A29G05 8
7381A34G01 10
7381A34G02 2
7381A61G01 4
7381A61G02 2
7381A73G01 3
7381A81G01 5
7381A83G02 20
7381A88G01 5
7381A93G03 60
7381A93G05 40
772B217G01 5
772B217G02 S 5
772B379G01 / 7380A27H01 5
772B379G01 1
772B387G01 4
772B450G01 5
772B450G02 5
772B452G01 5
9690A38G38
ABB YB161102-BV DSQC 129 R/D board
ABB YB161102-CH DSQC 136 Safety board
ABB YB161102-CM DSQC 138 Terminal unit
ABB YB560103-AC DSQC 202 Robot computer
ABB YB560103-AS DSQC 208A External axis board
ABB YB560103-AL DSQC 209 Analogue I/O board
ABB YB560103-AM DSQC 210 Safety board
ABB YB560103-AN DSQC 211 Power supply
ABB YB560103-BF DSQC 215 Robot computer
ABB YB560103-AZ DSQC 220 Programming board
ABB YB560103-BD DSQC 223 PC Board digital I/O
ABB YB560103-BE DSQC 224 PC Board combi I/O
ABB YB560103-BK DSQC 227 Winchester interface
ABB YB560103-BD DSQC 228 Safety board
ABB YB560103-BN DSQC 230 Robot computer
ABB YB560103-BS DSQC 233 External axis board
ABB YB560103-BY DSQC 235A Rectifier
ABB YB560103-BZ DSQC 235B Rectifier
ABB YB560103-CA DSQC 236A Drive unit
DSQC 236B Drive
ABB YB560103-CC DSQC 236C Drive unit
ABB 3HAB2207-1 DSQC 236D Drive unit
ABB YB560103-CD DSQC 236G Drive unit
ABB 3HAB2245-1 DSQC 236H Drive unit
ABB 3HAA3563-AJA DSQC 236P Drive unit
ABB YB560103-CE DSQC 236T Drive unit
DSQC 239 Board - ABB RIO
ABB DSQC 241 Power supply
ABB YB560103-CM DSQC 242 Programming board
ABB 3HAA0001-CP DSQC 243 Serial measurement board
ABB 3HAA3563-ACA DSQC 245 Serial measurement board
ABB 3HAA3563-AAA DSQC 248 Programming board
ABB 3HAA3563-AGA DSQC 249A Rectifier
ABB 3HAA3563-AHA DSQC 249B Rectifier
ABB 3HAA3563-AD DSQC 252 System board
E3HAC028756-001 DSQC 253 SMB unit DSQC 573
E3HAA3563-AMA DSQC 253 Serial Measurement Board
E3E 042816 DSQC 253 Exch. Serial mes. DSQC 253W
6369901-218 DSQC 253 Serial Measurement Board
ABB 3HAB2211-1 DSQC 256A System board
ABB 3HAA3563-AUA DSQC 258 Power supply
ABB 3HAB8797-1 DSQC 266B Drive unit
ABB 3HAB8798-1 DSQC 266C Drive unit
ABB 3HAB8801-1 DSQC 266G Drive unit
ABB 3HAB8800-1 DSQC 266H Drive unit
ABB 3HAB8799-1 DSQC 266K Drive unit
ABB 3HAB8802-1 DSQC 266T Drive unit
ABB 3HAA3573-AAA DSQC 300 Board - Computer
ABB 3HAB2210-1 DSQC 300 Board - Computer
ABB 3HAB2233-1 DSQC 300 Board - Computer
ABB 6369901-380 DSQC 300 Board - Computer
ABB 3HAA3573-ABA DSQC 301 Programming board
ABB 3HAB2209-1 DSQC 306 Computer board
ABB 6369901-298 DSQC 306 Computer board
ABB E3HAB2209-1 DSQC 306 Computer board
ABB 3HAB3700-1 DSQC 313 Serial measurement board
ABB 3HAB4259-1 DSQC 313 Serial measurement board
ABB 3HAC9522-1 DSQC 313 Serial Measurement Board
ABB 3HAB2215-1 DSQC 314A Rectifier
ABB 3HAB2216-1 DSQC 314B Rectifier
ABB 3HAB2231-1 DSQC 314C Rectifier DC b
ABB 6369901-336 DSQC 314C Rectifier DC b
ABB E3HAB2231-1 DSQC 314C Rectifier DC b
ABB 3HAB2214-1 DSQC 315 Combi I/O
ABB 3HAB2219-1 DSQC 316 Computer board
ABB 3HAB2209-1 DSQC 317 Memory expansion board
ABB 3HAB2233-1 DSQC 322 Robot computer
ABB 3HAB5956-1 DSQC 323 Memory expansion board
ABB 3HAB5957-1 DSQC 324 Memory expansion board
ABB 3HAB2241-1 DSQC 325 Main computer
ABB 3HAB2242-1 DSQC 326 Robot computer
ABB 3HAB7230-1 DSQC 327 Analogue Digital Combi I/O
ABB 3HAB7229-1 DSQC 328 Digital 24 VDC I/O
ABB 3HAB7215-1 DSQC 331 Panel unit
ABB 3HAC17973-1 DSQC 332 Digital relay I/O
ABB 3HAB5845-1 DSQC 334 Power supply
ABB 3HAB6182-1 DSQC 335 Robot computer
ABB 3HNE00001-1 DSQC 336 Network board NIOC-01
ABB 3HAB8101-1 DSQC 345A Rectifier
ABB 3HAB8101-2 DSQC 345B Rectifier
ABB 3HAB8101-3 DSQC 345C Rectifier
ABB 3HAB8101-4 DSQC 345D Rectifier
ABB 3HAB8101-14 DSQC 345E Rectifier
ABB 3HAB8101-5 DSQC 346A Drive unit
ABB 3HAB8101-6 DSQC 346B Drive unit
ABB 3HAB8101-7 DSQC 346C Drive unit
ABB 3HAB8101-11 DSQC 346E Drive unit
ABB 3HAB8101-8 DSQC 346G Drive unit
ABB 3HAB8101-13 DSQC 346U Drive unit
ABB 3HNE00957-1 DSQC 350 Remote I/O
ABB 3HNE00065-1 DSQC 354 Encoder interface
DSQC 355 I/O Board
ABB 3HAB8101-10 DSQC 358C Drive unit / Rectifier
ABB 3HAB8101-12 DSQC 358E Drive unit / Rectifier
ABB 3HAB8101-15 DSQC 358F Driveunit / Rectifier
ABB 3HAB8101-16 DSQC 358G Drive unit / Rectifier
ABB 3HAC0373-1 DSQC 361 Main computer
ABB 3HAC1462-1 DSQC 363 Robot computer
ABB 3HAC1620-1 DSQC 365 Power supply
ABB 3HAC3180-1 DSQC 373 Robot computer
ABB 3HAC3462-1 DSQC 374 Power supply
ABB 3HAC10597-1 DSQC 386 Devicenet gateway
ABB 3HAC3616-1 DSQC 500 Main computer
ABB 3HAC3619-1 DSQC 503 Axis computer
ABB 3HAC4297-1 DSQC 506 Power supply
ABB 3HAC5393-2 DSQC 508 Battery unit
ABB 3HAC5687-1 DSQC 509 Panel unit
ABB 3HAC7519-2 DSQC 518A Flash disk 64Mb
ABB 3HAC7519-3 DSQC 518B Flash disk 128Mb
ABB 3HAC8848-1 DSQC 522 I/O computer board
ABB 3HAC12158-1 DSQC 532 I/O Computer
ABB 3HAC14265-1 DSQC 539 Power supply
ABB 3HAC14279-1 DSQC 540 Main computer
ABB 3HAC16917-3 DSQC 544A Flash disk 64Mb
ABB 3HAC16917-4 DSQC 544B Flash disk 128Mb
ABB 3HAB8101-19 DSQC 545A Rectifier
ABB 3HAB8101-18 DSQC 546A Drive unit
ABB 3HAC17396-1 DSQC 562 Serial measurement board
ABB 3HAC022104-001 DSQC 564A Flash disk 64Mb
ABB 3HAC022104-002 DSQC 564B Flash disk 128Mb
ABB 3HAC020466-1 DSQC 627 Power supply
ABB 3HAC025918-001 DSQC 653 Digital relay
ABB 3HAC025465-004 DSQC 656 Flash disk 256Mb
ABB YB560103-BD DSQC223 I/O Card
ABB YB560103-BL DSQC228
ABB YB560103-CA DSQC236A DriveUnit
ABB 3HAA 3562-AGA/2 DSQC249A PowerUnit
ABB 3HAA 3563-ALA/2 DSQC252
ABB 3HAB 2211-1/1 DSQC256A
ABB 3HAB2213-1/3 DSQC313
ABB 3HAB6372-1 DSQC330 S4C Rechner Rack
ABB 3HAB7215-1/07 DSQC331 S4C Safety Board
ABB cable DSQC352 Profibus
ABB cannot find pn DSQC355 Analogbaugruppe
ABB YB161100-DP DSQS 174 Teach pendant S2
ABB YB161100-DR DSQS 174 Teach pendant S2
ABB 48990001-FE DSSR 115 Power supply
ABB 48990001-FK DSSR 116 Power supply
ABB 3HAC023195-1 Flexpendant Teach pendant IRC5
ABB 3HNE00313-1 TPU
YT212 002-A Rectifier
YT212 002-X Rectifier
ABB YT213001-BA YTE 102A Drive unit
ABB YT213001-BB YTE 102B Drive unit
ABB YT213001-BB YTE 102B Drive unit
ABB YT213001-BC YTE 102C Drive unit
YT213001-AC YTE 102C Drive
6369901-182 YTE 102C
EYT213001-BC YTE 102C
ABB YT212001-AF YTEA 250-15 Drive unit
ABB YT212001-AE YTEA 250-8 Drive unit
ABB YT212001-AB YYE 109A Power supply
ABB YT212001-AC YYT 102A Servo board
ABB YT212001-AD YYT 102B Servo board
ABB YT212001-AK YYT 102C Servo board
ABB YT212001-AT YYT 102D Servo board
ABB YT212001-AM YYT 102E Servo board
ABB YT212001-AN YYT 102F Servo board
ABB YT212001-AP YYT 102G Servo board
ABB YT212001-AR YYT 102H Servo board
ABB YT212002-AD YYT 107A Rectifier
Kuka 96 Roboter IR365/10 Langarm
Kuka 93 Roboter IR364/10/15
Kuka 98/99 Roboter KR125-2, 150, L150
Kuka 96 Roboter VKR125-1
Kuka 99 Roboter VKR125-2, VKR150
Kuka -00 Druckausgleich GA2-D.2
Kuka 96 VKRC1 Controller
Kuka 2000 VKRC1 Controller
Kuka 98/99 KRC1 Controller
Kuka 2000 KRC1 Controller
Kuka like new KRC1 Separat Controller Top
Kuka KRC1 Separat Controller Top
Kuka RC30/51c Controller
Kuka 71-052-214 MFC KRC1
71-039-272 with DSEAT
Kuka 00-117-336 DSE-IBS-C33
Kuka 71-039-271 RDW KRC1
Kuka 71-051-224 Motorleitung KRC1 7m
Kuka 71-051-225 Motorleitung KRC1 15m
Kuka Motorleitung KRC2 7m Serie2000
Kuka 00-106-496 Geberleitung KRC1/2 7m
Kuka 71-051-222 Geberleitung KRC1/2 15m
Kuka 00-127-94 Geberleitung KRC1/2 25m
Kuka 69-327-924 KRC32, PS15/67I
Kuka 69-327-921 KRC32, 3PS15/67I
Kuka 69-334-285 KRC32, NM100ABN
Kuka 69-223-650 KRC32, FE001/1
Kuka 69-223-653 KRC32, FE002/1-2
Kuka SEF 1b TP
Kuka 6FR2490-0AH12 KCP32 TP
Kuka 69-000-398 KCP1 TP
Kuka 00-110-185 KCP2 TP
Kuka 00-130-547 KCP2 TP
Kuka 69-000-399 VKCP1 TP
Kuka 00-107-264 VKCP2 TP
Kuka 00-132-347 KCP2
Kuka 6FX1404-0CC20 KCP32
Kuka 6FX1404-0CC10 KCP32 KUKA KCP2-00-110-185
Fanuc A05B - 2301 - 335
Fanuc TP Leitung
Fanuc EE-5188-201-014
Fanuc EE-5188-208-014
KSD1-16
KSD1-48
KSD1-32
KSD1-64
KSD1-08
KPS-600/20-ESC
KUKA KRC2 KSD1-48
KUKA KRC2 KSD1-32
KUKA KCP2-2005
DSQC 609 3HAC14178-1 1pcs
DSQC 662 3HAC026254-001 1pcs
DSQC 661 3HAC026253-001 2pcs
DSQC 652 3HAC025917-001 2pcs
DSQC 651 3HAC025784-001 2pcs
DSQC 655 3HAC025562-001 1pcs
4周
DSQC 328A 3HAC17970-1
DSQC 611 3HAC13389-2
DSQC 608 3HAC12934-1
DSQC 604 3HAC12928-1
DSQC 602 3HAC12816-1
DSQC 601 3HAC12815-1
DSQC 658 3HAC025779-001
DSQC 643 3HAC024488-001
DSQC604
DSQC 604
3HNE00313-1
3HAC14279-1/04 DSQC 540
DSQC679 3HAC028357-001
1. 视教器 3HAC028357-001
2. 电源 3HAC025917-001/00
3.伺服控制器 3HAC17282-1/07A
4.伺服控制器 3HAC14657-2/06A
5.伺服控制器 3HAC14549-3/12A
6.伺服控制器 3HAC14550-4/08A
7.伺服控制器 3HAC17281-1/03A
8.伺服控制器 3HAC025338-006/08A
9.QSDC652,10模块 3HAC026253-001
ABB 3HAB8101-11
ABB 3HAC14363-1
ABB 3HAC18159-1
ABB 3HNE00442-1
ABB 3HNE03277-1
ABB 3HNE06225-1
3HNE00314-1
3HNM07686-1
3HNM07485-1
YASKAWA JANCD-MM13B
