扫描周期是PLC的一个重要指标，小型PLC的扫描周期一般为十几毫秒到几十毫秒。PLC的扫描周期长短取决于扫描速度和用户程序的长短。

毫秒级的扫描时间对于一般工业设备通常是允许的，PLC对输入的短暂滞后也是允许的。但对某些I/O**响应的设备，则应采取相应的处理措施。如选择高速CPU，提高扫描速度；选择**响应模块、高速计数模块以及不同的中断处理等措施减少滞后时间。

对于用户来说，要提高编程能力，尽可能优化程序；而在编写大型设备的控制程序时，尽量减少程序长度，选择分支或跳步程序等，都可以减少用户程序执行时间。

Golnex NF-100 (411-761) 1/4", 750 RPM, 0.5 to 5 in-lbs, Torque Screwdriver

Golnex NF-200 (411-762) 3 to 12 lb-in Torque, 1000 RPM, Torque Screwdriver

Gore FB0HD0HD038.0 DCto 18 GHz, 38", APC-7, 50 Ohm, VNA Microwave RF Test Cable

Gould Valve Q-3T, 1/2" NPT, 10 to 400 psi, 120 V, 14 W, Solenoid Valve, !

Granville-Phillips 330, 4 Digit, Digital Ionization Gauge Controller

Greenlee 1904, High Leverage, Ratchet Knockout Driver Set, includes metal Case

Greenlee 1904, High Leverage, Ratchet Knockout Driver Set, includes metal Case

Greenlee 45082 Pair Tracing Probe Assembly, For 500 to 1.2 kHz Generators

Greenway Y-1618 50 MHz, +15 / -15 VDC, Precision Oscillator, Type N (M) to Mil

Grobet USA 33.722 1" x 1/4", 90° Angle, Standard Cut Deburring Tool (!)

Gurley 4320 Programmable, Automatic Digital Timer. Centronics + RS-232 Output.

H10S CLT-50 120 V Input, 60 Hz, 48 Watt, Torque Power Supply

HA Guden GGS21-090-1 (Lot of 2) 11.9"L, 3.5" Stroke, Chrome Gas Spring Rods

Hakko 936-12, 392° to 896°F, 65W, 120V, 60 Hz, Soldering Station Control Unit

Hakko FM-2024 120V, 12W, 60 Hz, Desolder Control Box; No additional accy's!

Hamlet 764L, 1", Locking, SS, Union Tee,

Hammond Power Systems (HPS) PH100MQMJ Industrial Control Transformer,

HARD / Tekelec 705bpi Data Line Analyzer, includes Carry Case, Manuals & Accy's

Hardinge 16DS 0.247 in. Dead Length Collet Assembly

Hardinge 16DS 0.254 in. Dead Length Collet Assembly

Hardinge 16DS 0.273 in. Dead Length Collet Assembly

Hardinge 16DS 0.317 in. Dead Length Collet Assembly

Hardinge 16DS 0.341 in. Dead Length Collet Assembly

Hardinge 16DS 0.341 in. Dead Length Collet Assembly

Hardinge 16DS 0.360 in. Dead Length Collet Assembly

Hardinge 16DS 0.372 in. Dead Length Collet Assembly

Hardinge 16DS 0.390 in. Dead Length Collet Assembly

Hardinge 16DS 0.390 in. Dead Length Collet Assembly

Hardinge 16DS 0.40" in. Dead Length Collet Assembly

Hardinge 16DS 0.412 in. Dead Length Collet Assembly

Hardinge 16DS 0.415 in. Dead Length Collet Assembly

Hardinge 16DS 0.425 in. Dead Length Collet Assembly

Hardinge 16DS 0.435 in. Dead Length Collet Assembly

Hardinge 16DS 0.470 in. Dead Length Collet Assembly

Hardinge 16DS 0.473 in. Dead Length Collet Assembly

Hardinge 16DS 0.478 in. Dead Length Collet Assembly

Hardinge 16DS 0.490 in. Dead Length Collet Assembly

Hardinge 16DS 0.493 in. Dead Length Collet Assembly

Hardinge 16DS 0.495 in. Dead Length Collet Assembly

Hardinge 16DS 0.522 in. Dead Length Collet Assembly

Hardinge 16DS 0.531 in. Dead Length Collet Assembly

Hardinge 16DS 0.553 in. Dead Length Collet Assembly

Hardinge 16DS 0.579 in. Dead Length Collet Assembly

Hardinge 16DS 0.670 in. Dead Length Collet Assembly

Hardinge 16DS 0.749 in. Dead Length Step Chuck Assembly

Hardinge 16DS 0.787 in. Dead Length Collet Assembly

Hardinge 16DS 0.900 - 0.800 in. Step, Dead Length Step Chuck Assembly

Hardinge 16DS 0.925 in. Dead Length Step Chuck Assembly

Hardinge 16DS Dead Length Emergency Collet Assembly. 1/4" Pilot Hole

Harris 0130-430402-001, BNC (F) All Ports, 2-Way, Coaxial IF Power Divider

Harting Han-Kit-16B (10330160000) 16 Poles + Ground, Bulkhead Housing, !

Hastings Instruments G-11 Analog Mass Air Meter (Vintage), includes Probe Assy.

Hastings Instruments G-11 Analog Mass Air Meter (Vintage), includes Probe Assy.

Hayward GG3025X25, 1/4" x 1/4", PPL Gauge Guard + FPM Diaphragm,

Helicoid Gauges, G4D1H3A0K0000, 0 to 1500 psi, 6" dial, Pressure Gauge, !

Heller Industries TC-6, Digital Component Counter, Reels & Accy's Not Included

Heller Industries TC-6, Digital Component Counter, Reels & Accy's Not Included

Hendry 0B2-20R, 10 Circuit Breaker, 20A Each, A/B Alarms, Fuse Panel Switch Unit

Hendry 0B2-20R, 10 Circuit Breaker, 20A Each, A/B Alarms, Fuse Panel Switch Unit

HI-Shear Spacematic M100 ll, 90 PSI, .45 HP, Precision Pneumatic Drill + Motor

Hitachi (Phillips) AT-10AN 250 MHz Oscilloscope Probe (! w/Accy's)

Hitachi Denshi HV-7214 24 VAC, 60 Hz, 7 Watt, CCTV Camera

Hitachi Deskstar IC35L080AVVA07-0, 80 GB, 7200 RPM, ATA / IDE, 3.5" Hard Drive

Hitachi HUS154545VLS300 PN 0B22890 16MB Cache, 450GB 3.5" Hard Drive + Tray,

Hitachi SJ300-037LFU, 3.7 kW, 5 HP, Variable Frequency Drive, Tested Working

Hitachi SJ300-075HFU, 10 HP (7.5 kW), Variable Speed Inverter / AC Drive, !

HNU PI 101 Portable Photoionization (PID) Analyzer, includes 10.2 eV Probe, Case

Hoffman E1PBA, 3.50" x 3.25" x 4.88", NEMA-13, IP65, Pushbutton Enclosure,

Hoffman F44L12, 4" x 4" x 12", NEMA-12, Steel, Lay-In Wireway Straight Section

Hoffman F44L12, 4" x 4" x 12", NEMA-12, Steel, Lay-In Wireway Straight Section

Hoffman F44L12, 4" x 4" x 12", NEMA-12, Steel, Lay-In Wireway Straight Section

Hoffman F44L12, 4" x 4" x 12", NEMA-12, Steel, Lay-In Wireway Straight Section

Hoffman F44L36, 4" x 4" x 36", NEMA-12, Steel, Lay-In Wireway Straight Section

Hoffman F44L36, 4" x 4" x 36", NEMA-12, Steel, Lay-In Wireway Straight Section

Hoffman F44L36, 4" x 4" x 36", NEMA-12, Steel, Lay-In Wireway Straight Section

Hoffman F44LA, 4" x 4" x 7", Gray Steel, Lay-In Wireway Telescoping Fitting