CLA-2 CO:R:C:G 086518 CMS

8504.90.00
8541.30.00
8541.50.00

Mr. Philip Y. Simons, Esq.
Freeman, Wasserman & Schneider
90 John Street
New York, NY 10038

RE: Reconsideration Of HQ 085027 (January 31, 1990); Thyristor Modules; Semiconductor Devices; Static Converters, Parts; High Voltage Direct Current (HVDC) Power Conversion Stations; Firing Circuitry; Voltage Divider Circuitry; Heatsinks

Dear Mr. Simons,

This is in response to your request dated February 9, 1990, on behalf of ABB Power Transmission, Inc. (ABB), for the reconsideration of HQ Ruling 085027 (January 31, 1990). Our ruling follows.

FACTS:

The merchandise is described by ABB as "thyristor modules". HQ Ruling 085027 held that the thyristor modules were classified as static converters in 8504.40.00, HTSUSA.

The modules are assemblies of electrical and mechanical devices and are approximately 4' long, 3' wide and 1' high. Each module consists of six thyristors, firing circuitry, voltage divider circuitry and cooling equipment. The components are assembled in a frame of epoxy resin and aluminum. The modules are used as parts of high voltage direct current (HVDC) power conversion stations.

Each of the six thyristors within a module consists of four alternative layers of doped silicon. The silicon layers are mounted in ceramic or metal casings in the form of discs approximately 6" to 8" in diameter.

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The voltage divider circuitry consists of capacitors and resistors, and functions to ensure that there is uniform voltage distribution across the six thyristors. The diagram of a thyristor module submitted with the October 17, 1989 submission shows a total of at least 28 capacitors and resistors within each module.

The firing circuitry facilitates the triggering pulses for the thyristors. Each of the six thyristors are fired simultaneously. The January 3, 1989 ruling request, p. 4, states that "ABB's thyristors are optically activated by use of a light signal propagated through fiber optic cables. During a typical firing sequence, the triggering pulse lasts only a few milliseconds."

The cooling equipment consists of seven heatsinks which are situated between the thyristors and at each end of the thyristor "column". The heatsinks are interconnected by cooling water tubing.

ISSUE:

Are the thyristor modules classified as parts of static converters in Heading 8504, or as semiconductor devices in Heading 8541?

LAW AND ANALYSIS:

Static converters and parts thereof are described by Heading 8504. Diodes, transistors and similar semiconductor devices are described by Heading 8541.

ABB argues that the modules cannot be classified in Heading 8504 as "parts" of static converters because they are described and classified as semiconductor devices in Heading 8541. ABB cites Chapter 85 Note 2, which provides in pertinent part that Heading 8504 does not apply to goods described in Heading 8541. ABB also cites Section XVI Note 2(a) and the general Explanatory Notes to Section XVI. Section XVI Note 2(a) in pertinent part states that parts which are goods included in any of the headings of chapters 84 or 85 are classified in their respective headings; the General Explanatory Notes to Section XVI, p. 1131, provide in pertinent part that articles, including "diodes, transistors, etc., of heading 85.41", which constitute an article covered by a heading of Section XVI are classified in their own appropriate heading.

ABB submits that the thyristor modules are described by Heading 8541 as "similar semiconductor devices". The -3-

Explanatory Notes to Heading 8541, p. 1397, provide:

Similar semiconductor devices. The "similar" devices referred to here are semiconductor devices whose operation depends on variations in resistivity in the application of an electric field.

They include:

(1) Thyristors, consisting of four conductivity regions in semiconducting materials (three or more p n junctions) through which a direct current passes in a predetermined direction when a control pulse initiates conductivity. They are used as controlled rectifiers, as switches or as amplifiers and function as two interlocking, complementary transistors with a common collector/base junction.

The Explanatory Notes to Heading 8541 also provide that the four conductivity regions of semiconducting material can be assembled with certain types of articles used to mount the semiconducting material. The Explanatory Notes, p. 1398 provide:

The devices described above fall in this heading whether presented mounted, that is to say with their terminals or leads or packaged (components), unmounted (elements) or even in the form of undiced discs (wafers).

Each of the six individual thyristors within a module appear to be described as Heading 8541 similar semiconductor devices. They consist of four conductivity regions in semiconducting silicon material mounted in a metal or ceramic casing. The operation of the individual thyristors depends on variations in resistivity in the application of an electric field, and the definition of Heading 8504 semiconductors provided in Chapter 85 Note 5(A) is thus satisfied as to the individual thyristors. If the merchandise under consideration consisted of just thyristors, it would apparently be classified in Heading 8541.

However, the merchandise at issue is not thyristors. The merchandise consists of thyristor modules. The thyristors within a module are only one type of device in a complex assembly comprised of many types of devices. The firing circuitry, voltage divider circuitry and cooling equipment are not "semiconductor" devices and are not mere mountings or packaging for semiconductor devices. The firing circuitry, voltage divider

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circuitry and cooling equipment are essential to the function of the thyristor modules and are assembled together with the thyristors for the specific purpose of working in a HVDC power conversion station.

The thyristor modules are only partly described by Heading 8541, but are fully described by Heading 8504 which covers static converters and parts thereof.

The Explanatory Notes to Heading 8504, p. 1338, provide that Heading 8504 semiconductor converters "...consist of a semiconductor as the converting element and various other devices (e.g., coolers, tape conductors, drives, regulators, control circuits) (emphasis added). The Explanatory Notes further provide at p. 1338, that Heading 8504 semiconductor converters include "semiconductor rectifiers using, as a converting element, a device containing silicon or germanium crystals (e.g., diode, thyristor, transistor)" (emphasis added).

The thyristor modules under consideration contain a semiconductor as the converting element (thyristor) and various other devices (cooling equipment, firing circuitry, voltage divider circuitry), assembled for use as part of a Heading 8541 converter.

The thyristor modules do not contain all the devices needed to form complete Heading 8504 converters. They do, however, contain enough devices to be identified and described as articles solely or principally used as parts of Heading 8504 static converters.

ABB submits the following additional arguments in support of the classification of the thyristor modules in Heading 8541: (1), the Explanatory Notes to the Combined Nomenclature of the European Community support the classification in Heading 8541; (2), the modules are analogous to certain transistor modules classified in Heading 8541 in two HQ Rulings; (3), the modules are classified in Heading 8541 as composite machines pursuant to Section XVI Note 3; (4), the modules are classified in Heading 8541 as functional units pursuant to Section XVI Note 4; (5), if the modules are not classified as thyristors in subheading 8541.30.00, then they are classified as other semiconductor devices in subheading 8541.50.00; (6), the Explanatory Notes to Heading 8541 regarding piezo-electric crystals support the classification of the thyristor modules in Heading 8541.

ABB cites the Explanatory Notes to Heading 8504 of the Combined Nomenclature of the European Community. These Notes are cited in support of the argument that the EEC would exclude the thyristor modules from Heading 8504 because they are not combined

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with a transformer or resistor. However, the thyristor modules do combine thyristors with the resistors in the voltage divider circuitry. Further, the EEC Explanatory Notes (1988 and 1989 Editions), merely provide that multiple silicon elements are not included in Heading 8504 "...provided they are not combined with another electrical element such as a transformer or resistor" (emphasis added). In addition to the voltage divider circuitry, the silicon elements in the thyristor modules are combined with the electrical elements of the firing circuitry. Finally, the EEC Explanatory Notes to Heading 8504 appear to provide that Heading 8541 articles may be fitted with a cooling device, but it has not been established that the cooling device may be as substantial as heatsinks interconnected by cooling water tubing.

HQ Rulings 084659 (August 25, 1989) and 084660 (September 7, 1989) are cited in ABB's Request For Reconsideration in support of the argument that the thyristor modules are classified in Heading 8541. These two rulings classified transistor modules consisting of multiple transistor diodes in Heading 8541 as transistors. ABB highlights the similarities between the transistor and thyristor modules which both incorporate multiple semiconductor elements. However, ABB does not address the substantial differences between the modules. Unlike the transistor modules, the thyristor modules incorporate firing circuitry which facilitates the triggering pulses for the semiconductor devices. The voltage divider circuitry of the thyristor modules is not analogous to whatever resistors may be present in the transistor modules. Transistors and thyristors are different types of semiconductors and are described differently in the Explanatory Notes to Heading 8541. The transistor modules meet the common meaning of "transistor" and the description of transistors in the Explanatory Notes; the thyristor modules do not meet the common meaning of "thyristor" and the description of thyristors in the Explanatory Notes. Unlike the transistor modules, the thyristor modules are designed for the specific purpose of functioning as part of a Heading 8541 static converter.

ABB also argues that the thyristor modules are classified in Heading 8541 as Section XVI Note 3 "composite machines". ABB quotes and discusses certain portions of Section XVI Note 3, but does not address the first five words of Note 3: "Unless the context otherwise requires" (emphasis added). The context requires that the thyristor modules be classified pursuant to a Section XVI Note other than Note 3. The modules are parts of machines and Section XVI Note 2 provides specific classification rules for parts of machines. The modules are not any of the goods included in any of the headings of Chapters 84 or 85 and thus they are not classified pursuant to Note 2(a). Instead, the modules are parts suitable for use solely or principally with -6-

static converters and are classified as parts in Heading 8504 pursuant to Section XVI Note 2(b). Further, the thyristor modules are not similar to the exemplars of "composite machines" provided in the General Explanatory Notes to Section XVI, p. 1133 (e.g., printing machine, box making machine, industrial furnace, cigarette making machine); unlike the thyristor modules, the exemplars are identifiable as essentially complete machines and are not identifiable merely as parts of machines.

ABB cites HQ Ruling 085577 (January 10, 1990) in support of the composite machine argument. HQ 085577 found that an audio rack system comprised of an amplifier, tuner and cassette deck was not a Section XVI composite machine because the components were not sufficiently "fitted together to form a whole". ABB's argument that the thyristor modules are "fitted together" does not establish that the modules are composite machines. The thyristor modules are "parts" classified pursuant to Section XVI Note 2, and are not classified pursuant to Section XVI Note 3 like the General Explanatory Note exemplars. It has not been established that a thyristor module, which is merely a part, is considered to be a "whole" pursuant to Section XVI Note 3. Further, ABB's attempt in its July 13, 1990 submission to directly apply the criteria for a GRI 3(b) composite good to the classification of a Section XVI composite machine is unsupported; GRI 3(b) composite goods are classified according to GRI 3, whereas Section XVI composite goods are provided for in section notes and are classified according to GRI 1.

ABB argues that the thyristor modules are classified in Heading 8541 as Section XVI Note 4 "functional units". Section XVI Note 4 provides that the components of functional units "...contribute together to a clearly defined function covered by one of the headings in chapter 84 or chapter 85..." (emphasis added). The thyristor modules do not satisfy the requirements of Section XVI Note 4. Although the function of the individual thyristors within a module may be described by Heading 8541, the individual thyristors are incorporated in a complex assembly with firing circuitry, voltage divider circuitry and certain cooling equipment. Heading 8541 clearly does not describe the function of these other devices, and nothing in Heading 8541 suggests that it was intended to cover the complex assembly under consideration. ABB argues that the modules function like a single "semiconductor gate". However, Heading 8541 describes "semiconductor devices" and only the thyristors within the thyristor modules are semiconductor devices. The thyristor modules function as they are intended, i.e., as assemblies of six semiconductor devices combined with other devices for the sole function of working in a HVDC power conversion station. If there is a heading which describes the function of the modules, it is Heading 8504 which describes parts of static converters. The -7-

modules, however, are merely "parts" and are classified according to Section XVI Note 2, not Section XVI Note 4.

ABB cites HQ Ruling 086851 (April 9, 1990) in support of the functional unit argument. However, the thyristor modules are not analogous to the functional units under consideration in HQ 086851, which were essentially complete units and had clearly defined functions covered by a particular heading (e.g., automatic data processing machines, Heading 8471; printers, Heading 8471; chromatographic analysis equipment, Heading 9027). Further, the thyristor modules are mere parts and are not similar to the exemplars of functional units provided in the General Explanatory Notes to Section XVI, pp. 1133-1134.

ABB argues that if the thyristor modules are not classifiable as "thyristors" in subheading 8541.30.00, then they are classified as "other semiconductor devices" in subheading 8541.50.00. The thyristor modules are not classified as "other semiconductor devices". The semiconductor devices within the modules are thyristors, not some other semiconductor device. In any event, only part of the thyristor modules consist of any type of semiconductor device described by Heading 8541. The modules incorporate semiconductor devices (i.e., thyristors), and non- semiconductor devices (i.e., firing circuitry, voltage divider circuitry, cooling equipment). They are only partly described by Heading 8541, but are fully described as parts of Heading 8504 static converters consisting of semiconductor elements and certain other devices.

ABB argues that the Explanatory Notes to Heading 8541 regarding mounted piezo-electric crystals support the classification of the thyristor modules in Heading 8541. The Explanatory Notes, p. 1399, provide:

If, however, because of the addition of other components, the complete article (mounting plus crystal) can no longer be regarded as merely a mounted crystal but has become identifiable as a specific part of a machine or appliance, the assembly is classified as a part of the machine or appliance in question;

ABB argues that because similar language is not included in the Explanatory Notes for "similar semiconductor devices", the principle embodied in the language was not intended to apply to "similar semiconductor devices". This is simply not the case. This Explanatory Note language illustrates Section XVI Note 2, which except for some inapplicable headings, applies to Section -8-

XVI "parts" including thyristor modules. The Explanatory Note language and Section XVI Note 2 require that mounted piezo- electric crystals which have been assembled with other components and are thus no longer mere mounted crystals, are not classified as mounted crystals in Heading 8541; instead, the articles are classified as parts of the machine or appliance in question pursuant to Section XVI Note 2(b). Similarly, Heading 8541 similar semiconductor devices (e.g., thyristors), which have been assembled with other components (e.g., firing circuitry, voltage divider circuitry, cooling equipment) and can no longer be regarded as mere semiconductor devices, are classified as a part of the machine or appliance in question (e.g., part of Heading 8504 static converter).

The thyristor modules are not described as Heading 8541 similar semiconductor devices. They are described by Heading 8504 and are classified as parts of static converters in 8504.90.00, HTSUSA.

HOLDING:

HQ Ruling 085027 (January 31, 1990) is modified to provide that the thyristor modules are classified as parts of static converters in 8504.90.00, HTSUSA.

Sincerely,

Harvey Fox
Director, Office of
Regulations and Rulings