CLA-2 CO:R:C:M 957510 DWS

Ms. Sandy M. Rickert
E. Besler & Company
P.O. Box 66361
Chicago, IL 60666-0361

RE: Photosensors; Safety Light Curtains; Optical Coupled Sensors; Explanatory Notes 85.41(B) and (C); HQ 088341; Chapter 85, Note 5; 8536.50.80

Dear Mr. Rickert:

This is in response to your letter of August 26, 1994, on behalf of Micro Switch, to the Area Director of Customs, New York Seaport, concerning the classification of photoelectric sensors and safety light curtains under the Harmonized Tariff Schedule of the United States (HTSUS). We have also considered information provided in a letter dated November 4, 1994, from Micro Switch, in preparing this ruling.

FACTS:

The merchandise consists of photoelectric sensors and safety light curtains. It is our understanding that both items operate in a similar manner. Each consists of a light emitting diode (LED) and a photo darlington transistor. Both of these components are mounted so that the light emitted by the LED is directed at the surface of the photo darlington transistor. This configuration allows a target to be detected when the LED light path is interrupted. The photosensor will respond to a target's presence or absence using either digital or analog intelligence to perform such functions as positioning, switching, measuring, and/or diagnostics. The safety light curtain will react to the interruption of the LED light path by shutting down a power driven machine in which it is contained to protect the machine's operator.

The subheadings under consideration are as follows:

8536.50.80: [e]lectrical apparatus for switching or protecting electrical circuits, or for making connections to or in electrical circuits (for example, switches, relays, fuses, surge suppressors, plugs, sockets, lamp- holders, junction boxes), for a voltage not exceeding 1,000 V: [o]ther switches: [o]ther.

The general, column one rate of duty for goods classifiable under this provision is 4.8 percent ad valorem.

8541.40.80: . . . : [p]hotosensitive semiconductor devices, including photovoltaic cells whether or not assembled in modules or made up into panels; light-emitting diodes: [o]ther: [o]ptical coupled isolators.

Goods classifiable under this provision receive duty-free treatment.

ISSUE:

Whether the photoelectric sensors and the safety light curtains are classifiable under subheading 8536.50.80, HTSUS, as other electrical apparatus for switching electrical circuits, or under subheading 8541.40.80, HTSUS, as optical coupled isolators.

LAW AND ANALYSIS:

Classification of merchandise under the HTSUS is in accordance with the General Rules of Interpretation (GRI's). GRI 1 provides that classification is determined according to the terms of the headings and any relative section or chapter notes.

In understanding the language of the HTSUS, the Harmonized Commodity Description and Coding System Explanatory Notes may be utilized. The Explanatory Notes, although not dispositive or legally binding, provide a commentary on the scope of each heading of the HTSUS, and are generally indicative of the proper interpretation of these headings. See T.D. 89-80, 54 Fed. Reg. 35127, 35128 (August 23, 1989). In part, Explanatory Notes 85.41(B) and (C) (pp. 1398 - 1399) states that:

(B) PHOTOSENSITIVE SEMICONDUCTOR DEVICES

This group comprises photosensitive semiconductor devices in which the action of visible rays, infra-red rays or ultra- violet rays causes variations in resistivity or generates an electromotive force, by the internal photoelectric effect. . .

The main types of photosensitive semiconductor devices are:

(1) xxx

(2) Photovoltaic cells, which convert light directly into electrical energy without the need for an external source of current. Photovoltaic cells based on selenium are used mainly in luxmeters and exposure meters. Those based on silicon have a higher output and are used, in particular, in control and regulating equipment, for detecting light impulses, in communication systems using fibre optics, etc.

Special categories of photovoltaic cells are:

(i) xxx

(ii) Photodiodes (germanium, silicon, etc.), characterised by a variation in resistivity when light rays strike their p n junction. They are used in automatic data processing (reading of punched cards and tapes, data storage), as photocathodes in certain electronic tubes, in radiation pyrometers, etc. Phototransistors and photothyristors belong to this category of photoelectric receivers. . .

(iii) Photocouples and photorelays consisting of electroluminescent diodes combined with photodiodes, phototransistors or photothyristors.

Photosensitive semiconductor devices fall in this heading whether presented mounted (i.e., with their terminals or leads), packaged or unmounted.

(C) LIGHT EMITTING DIODES

Light emitting diodes, or electroluminescent diodes, (based, inter alia, on gallium arsenide or gallium phosphide) are devices which convert electric energy into visible, infra-red or ultra-violet rays. They are used, e.g., for displaying or transmitting data in control systems.

In HQ 088341, dated February 26, 1991, we held that photosensors, similar to the subject merchandise, were classifiable under subheading 8541.40.80, HTSUS. In that ruling, we stated that:

[t]he photosensor at issue consists of a LED and photo- transistor combined together as one unit. An LED is described with electroluminescent diodes as devices which convert electric energy into visible, infra-red or ultra- violet rays. EN 85.41(C). A phototransistor is described as a type of photoelectric receiver characterized by a variation in resistivity when light rays strike its p n junction. EN 85.41(B)(2)(ii). The phototransistor at issue operates by receiving rays from the LED which create a variation in resistivity. When these rays are interrupted, by a shaft or key in some cases, this variation in resistivity ceases. Accordingly, the photosensor satisfies the description of a photosensitive semiconductor device consisting of an electroluminescent diode combined with a phototransistor.

Subheading 8541.40.80, HTSUS, provides for optical coupled isolators. These are described as very small four-terminal electronic circuit elements that include in an integral package a light emitter and light detector. McGraw-Hill Encyclopedia of Science and Technology (MH) (6th ed.), vol. 12, p. 419 (1987). The optical emitters most commonly used in an isolator are LEDs. MH at 419. As stated previously, the photosensor contains a LED. A type of light detector used in isolators are light-sensitive devices that modify a voltage or current such as phototransistors. MH at 419. As stated previously, the subject photosensor contains a phototransistor. Furthermore, a LED-silicon detector combination is cited as a type of optical coupled isolator. MH at 419. A photo-darlington sensor is cited as a type of light detector used in a LED-silicon detector. MH at 420. Accordingly, the photosensor satisfies the description of an optical coupled isolator.

It is our position that, as with the photosensors in HQ 088341, the subject photoelectric sensors and the safety light curtains are classifiable under subheading 8541.40.80, HTSUS, as optical coupled isolators. In an optical isolator, the emitting and detecting devices are so positioned that the majority of the emission from the emitter is optically coupled to the light-sensitive area of the detector. This configuration uses an electronic input signal to cause an electronic input signal without any electronic connection between the input (LED) and the output (phototransistor) terminals. The subject merchandise satisfies this description. It is our understanding that both the photoelectric sensors and the safety light curtains are configured in such a way that the light emitted by the LED is optically coupled to the light-sensitive area of the photo darlingtion transistor. When the rays emitted by the LED are broken by a target, the isolator is no longer coupled and does not produce an output signal. In addition, no electrical connection exists between the LED and photo darlington transistor within the merchandise. Therefore, based upon the information you have submitted, the merchandise satisfies the descriptions of how an optical coupled isolator functions.

Consideration was given to classification of the merchandise under subheading 8536.50.80, HTSUS, as other electrical apparatus for switching electrical circuits. However, as we stated in HQ 088341, the merchandise does not meet any of the technical descriptions of switches, nor is the merchandise similar to any of the exemplars listed under Explanatory Note 85.36.

In part, chapter 85, note 5, HTSUS, states that:

[f]or the classification of the articles defined in this note, headings 8541 and 8542 shall take precedence over any other heading in the tariff schedule which might cover them by reference to, in particular function, their function.

Even if the photoelectric sensors and the safety light curtains were described under heading 8536, HTSUS, based upon chapter 85, note 5, HTSUS, classification of the merchandise under heading 8541, HTSUS, would take precedence over classification under heading 8536, HTSUS.

Therefore, the merchandise is classifiable under subheading 8541.40.80, HTSUS, as optical coupled sensors.

HOLDING:

The photoelectric sensors and the safety light curtains are classifiable under subheading 8541.40.80, HTSUS, as optical coupled sensors.

Sincerely,

John Durant, Director
Commercial Rulings Division