PLC是采用“顺序扫描，不断循环”的方式进行工作的。即在PLC运行时，CPU根据用户按控制要求编制好并存于用户存储器中的程序，按指令步序号（或地址号）作周期性循环扫描，如无跳转指令，则从第一条指令开始逐条顺序执行用户程序，直至程序结束。然后重新返回第一条指令，开始下一轮新的扫描。在每次扫描过程中，还要完成对输入信号的采样和对输出状态的刷新等工作。

PLC的一个扫描周期必经输入采样、程序执行和输出刷新三个阶段。

PLC在输入采样阶段：首先以扫描方式按顺序将所有暂存在输入锁存器中的输入端子的通断状态或输入数据读入，并将其写入各对应的输入状态寄存器中，即刷新输入。随即关闭输入端口，进入程序执行阶段。

PLC在程序执行阶段：按用户程序指令存放的先后顺序扫描执行每条指令，经相应的运算和处理后，其结果再写入输出状态寄存器中，输出状态寄存器中所有的内容随着程序的执行而改变。

输出刷新阶段：当所有指令执行完毕，输出状态寄存器的通断状态在输出刷新阶段送至输出锁存器中，并通过一定的方式（继电器、晶体管或晶闸管）输出，驱动相应输出设备工作。

 

MAXON MOTOR 241693 Planetary Gearhead , DC motor sn:863495

MAXON MOTOR 241693 Planetary Gearhead , DC motor sn:828576

MAXON MOTOR 225256 Planetary Gearhead , DC motor sn: b.b

MAXON MOTOR 241693 Planetary Gearhead , DC motor sn:137562

MAXON MOTOR 225256 Planetary Gearhead , DC motor sn: a.b

MAXON MOTOR 108302 MOTOR ConTROL ***XLNT***

TACHO GEN FOR MAXON MOTOR

PD-1012 CCS Box Vision Light Power Supply

Maxon Motor Model 273850

Maxon Motor 44.022.000-00.09-405 806534 DC Motor

MAXON DC MOTOR & GEAR,MINI,MICRO 41.022.022-00.00-902 DC Motor

Maxon EC Motor P/N 169008 NEW! $50

Maxon motor 384197 with HEDL-5540 A02 Encoder

Swiss Maxon 2642 11 pole coreless motor BB zero cogging

Swiss Maxon 1538 5 pole coreless motor with gearhead

MAXON DC MOTOR & GEAR,MINI,MICRO A-MAX

MAXON DC MOTOR ,MINI,MICRO A-MAX 44.026.000-00.09-140

NEW Maxon Motor Controller # 108302, WARRANTY

Maxon Motor Control Aluminum Machined Bracket Servo Amp Driver Brushless DC

Swiss Maxon 1640 7 pole coreless motor-double shafts

Swiss Maxon 13 mm 7 pole coreless motor-High torque

MAXON 41.032.038-00.00-289 ,DC Motor gear

Maxon Encoder Motor 24VDC 42rpm w/ Gear ratio 250:1

From Hong Kong

maxon A-max 169387 motor With gear & HEDS-5540 A01,Swiss made

MAXON ASML 4022 436 6810 DC MOTOR #42

Maxon motor 145577 with HEDS-5540 A11

Swiss Maxon 1335 7 pole coreless motor-High torque

Swiss Maxon 2642 13 pole coreless motor w zero cogging

Maxon motor 350008 with HEDL-5540 A02 0807A

MAXON Motor DC Encoder HEDL 5540

From Spain

MAXON 8 WATT PRECISION EC BRUSHLESS DC SERVO MOTOR

Maxon 124342 DC Motor

Maxon 124344 DC Motor

Maxon Motor Controller # 108302

Used Swiss MAXON DC Motor 41.013.013-00.00-197 DC12-24V

maxon A-max 169387 motor With gear & HEDS-5540 A01,Swiss made

Swiss maxon 2229 5 pole coreless motor coasts smoothly

Swiss Maxon 1629 7 pole coreless motor internal flywheel and 22 mm shaft

Swiss Maxon 1625 7 pole coreless motor double shafts

Swiss Maxon Motor for Robot (13mm dia) 12VDC 235RPM

From Hong Kong

Maxon Motor A-max - 26 mm Dia x 45 mm Long - 9500 RPM - 7.2 V - High Precision

Swiss maxon 2231 9 pole coreless motor coasts smoothly

Swiss MAXON Motor M000121A with serial port connection

Used Swiss MAXON DC Motor 139885 DC12V

Used Swiss MAXON DC Motor 41.013.013-00.00-200 DC12V

Maxon dc motor 41.022.024-00.00-164 with maxon gear 2924.814-0020.0-000

maxon DC motor 2326.938-12.111-050,Swiss made

Used Swiss MAXON DC Motor 118593 DC18V

Maxon A-max 12 Gear Motor

Maxon A Max 140644 Motor #92121546 Mixing Pot Assembly

MAXON STO-A 2 N. GAS 3/4'' MOTORIZED VENT VALVE

MAXON HYD. PUMP PERMANENT MAGNENT MOTOR MA253324

MAXON 44.060.000-00.09-102 MOTOR DC CVTR CAROUSEL

Maxon DC Robot Motors REF. 148810 RE-15-1-K05 Stablizer Ref. D22124600

Maxon 145247 Motor

Maxon Motor 44.060.000-00.09-071 112-087 Shuttle Motor SVG Lithography

MAXON SHUT-OFF VALVE-2 1/2''- 5000/0-264 VA-24VA-6SEC-1-1 120/60 MOTOR

MAXON RE025-055-35EBA201A DC SERVO MOTOR + TACHO 5.2:1