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E = Voltage / I = Amps / PF = Power Factor / EFF = Efficiency / HP = Horsepower
To Find	Direct Current	Alternating Current
To Find	Direct Current	Single Phase	*Two-Phase Four-Wire**	Three Phase
Amperes when Horsepower is known	HP x 746 --------------- E x EFF	HP x 746 ---------------- E x EFF x PF x 2	HP x 746 --------------------------- 2 x E x EFF x PF	HP x 746 ------------------ E x EFF x PF x 1.73
Amperes when Kilowatts are known	KW x 1000 ----------------- E	KW x 1000 --------------------- E x PF	KW x 1000 ------------------- 2 x E x PF	KW x 1000 ------------------ E x PF x 1.73
Amperes when "KVA" is known		KVA x 1000 ------------------- E	KVA x 1000 --------------------- 2 x E	KVA x 1000 ---------------------- E x 1.73
Kilowatts	E x I -------------- 1000	E x I x PF ---------------- 1000	I x E x 2 x PF -------------------------- 1000	E x I x 1.73 x PF ------------------- 1000
Kilovolt-Amperes "KVA"-		I x E ------------- 1000	I x E x 2 ------------------------ 1000	E x I x 1.73 -------------------- 1000
-Horsepower (Output)	E x I x EFF ----------- 746	E x I x EFF x PF ---------------- 746	I x E x 2 x EFF x PF ----------------------------- 746	E x I x EFF x PF x 1.73 --------------------------------- 746

Note: Direct current formulas do not use (PF, 2, or 1.73)
Single phase formulas do not use (2 or 1.73)
Two phase-four wire formulas do not use (1.73)
Three phase formulas do not use (2)
* For three-wire, two phase circuits the current in the common conductor is 1.41 times that in either of the other two conductors.

The term "line noise" refers to random fluctuations - electrical impulses that are carried along with standard AC current. Turning on fluorescent lights, laser printers, working near a radio station, using a power generator, or even working during a lightening storm can all introduce line noise into systems.

Line noise interference can result in many different symptoms depending on the situation. Noise can introduce glitches and errors into programs and files. Hard Drive components can be damaged. Televisions and computer screens can display interference as "static" or "snow," and audio systems experience increased distortion levels.

    Surge suppressors, Line conditioners and UPS units include special noise filters that remove or reduce line noise. The amount of filtration is indicated in the technical specifications for each unit. Noise suppression is stated as Decibel level (dB) at a specific frequency (kHz or MHz). The higher the dB, the greater the protection.
    Be wary of "surge/noise suppressors" that don't provide this information. Some surge suppressors (Such as the Tripp Lite Isobar suppressors) take noise suppression to a new level with Isolated Filter Banks. These special banks prevent line noise generated from one device from traveling through the surge suppressor to interfere with other equipment.
    Using a laser printer (a notorious source for line noise) connected to the same suppressor that powers a computer will not endanger the computer.

Power surges are an increase in the voltage that powers electrical equipment. Surges often go unnoticed, often lasting only 1/20th of a second, but they are much more common and destructive than you might think. According to recent studies, electrical equipment is constantly experiencing surges of varying power. Some of them can be absorbed by a power supply while others can only be handled by a quality surge suppressor. The most destructive power surges will wipe out anything that gets in their way!

In this power-hungry computer age, utility power systems are often pushed beyond their capacity, resulting in unstable, unreliable power for consumers. Overburdened power grids can generate powerful surges as they switch between sources or generate "rolling surges" when power is momentarily disrupted. Local sources can also generate surges (such as a motor starting, or a fuse blowing out).

Lightening can generate a spectacular surge along any conductive line to destroy everything in its path. NO MATTER WHAT MANUFACTURERS MAY CLAIM, NO SURGE SUPPRESSOR IN THE WORLD CAN SURVIVE A DIRECT LIGHTENING STRIKE. However, with quality equipment the surge suppressor will take the hit - ending up melted - but the equipment it protects will not be affected.

The bigger, the better! Joule ratings measure a surge suppressors ability to absorb surges.

Higher ratings offer more protection. Amp levels are another important factor in determining surge strength. Look for the highest amp protection levels available.

Underwriter Laboratories tests each surge suppressor and rates them according to the amount of voltage they let-through to connected equipment. The lower the let-through voltage, the better the surge suppressor is. UL established the 330 volt let-through as the benchmark because lower ratings added no real benefits to equipment protection, while surge components, forced to work harder, failed prematurely. Be wary of manufacturers claiming lower let-through ratings.

Sensing: The inductive proximity will sense all metals. The exact point at which a target will be detected is influenced by the type of metal, its size and surface area. The following charts show the sensing fields for a standard target: 45mm sq., mild steel, 1mm thick.

The two most common approach directions are axial (head-on) and lateral (from the side). Detection occurs at the point where the target first touches the envelope of the sensing curve. The curve shown is for a standard target and must be corrected for other size targets.

Correction Factors for Typical Target Materials Based on Standard Size
Target Material	Corrective Factor
Steel 1020	1.00
430 Stainless	1.03
302 Stainless	.85
Brass	.50
Aluminum	.47
Copper	.40

This type of sensor detects the reflection of transmitted light from the surface of an object. Shortest sensing range of all photoelectrics.

This type of sensor utilizes a special reflector to return the beam directed at it from the sensor. An object between the sensor and reflector is senses when it interrupts the beam. Medium sensing range.

Separate emitter and receiver provide maximum detection range and most positive type of sensing for opaque objects. When an object interrupts the beam from emitter to receiver, the object is detected.

2-Wire Devices: 2-wire sensors are intended to be connected tin series with the controlled load. Because these sensors derive the power to energize their internal electronics through the load they control, a minimum current is drawn through the load when the sensor is in the open stat. This current is so small that it can be ignored and will not turn on electro-mechanical devices such as relays and solenoids. However, this current could be enough to operate an electronic load. Cutler-Hammer's 2-wire sensors have the lowest leakage current in the industry and are suitable for many electronic loads.

3-WIRE DEVICES: 3-wire sensors derive their power directly across the line and therefore have no current leakage to the load.

Operation of Logic Modules
On Delay	Adjustable delay between time object is sensed and time switch function occurs.
Off Delay	Adjustable delay between time object leaves sensing field & time switch transfers back to non-sensing state.
On & Off	Combination of Above.
Delayed Single Shot	Adjusts length of time switch remains in "ON' cycle after object is sensed regardless of length of time object stays in sensing field. "ON" cycle can also be delayed after object is first detected.

Allowable Ampacities Insulated
Conductors (In a Raceway)
Table 310-16 1996 N.E.C.

* Unless otherwise specifically permitted elsewhere in the National Electrical Code Book, the overcurrent protection for conductor types marked with an asterisk shall not exceed 15 amperes for No. 14, 20 amperes for No. 12 & 30 amperes for No. 10 copper; or 15 amperes for No. 12 & 25 amperes for No. 10 aluminum & copper-clad aluminum after any correction factors for ambient temperature & number of conductors has been applied.