Square D 4800 User manual

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Hospital Isolated Power Systems

Class 4800

CONTENTS Description Page

General Information and Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Product Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25

Contents

SECTION 1–GENERAL INFORMATION AND APPLICATION

OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

HISTORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

ELECTRICAL HAZARDS IN HOSPITALS . . . . . . . . . . . . . . . . . . . . . . . . .4

Leakage Currents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

CODES AND STANDARDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

NFPA No. 99 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Anesthetizing Location Classifications . . . . . . . . . . . . . . . . . . . . . . .6

Article 517, National Electrical Code—NFPA No. 70 . . . . . . . . . . . . . .7

Patient Care Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Anesthetizing Location Classifications . . . . . . . . . . . . . . . . . . . . . . .8

UL 2601-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

UL 1022 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

UL 1047 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

ISOLATED SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Ungrounded System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

System Comparison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Imperfect Isolating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Line Isolation Monitor (LIM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

Types of LIMs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

GROUNDING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Electric Equipment Power Cord Grounding . . . . . . . . . . . . . . . . . . . . .14

Permanently Installed Ground System (Hard Wiring) . . . . . . . . . . . . .14

Equipotential Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

Ground Jacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

I. System Concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

II. Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

III. General Application Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

A. System Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

B. System Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

C. System Wiring and Conduit . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

IV. System Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

A. Operating Room Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

B. Portable X-Ray System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

C. Interlocking Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

D. Surgical Facility Panels (SFP) . . . . . . . . . . . . . . . . . . . . . . . . . .20

V. Field Test and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

ELECTRICAL MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Isolated Power System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

LIM Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Ground Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Adapters and Extension Cords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Medical Equipment Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

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SECTION 2–PRODUCT DESCRIPTIONS

SURGICAL FACILITY PANELS (SFP) . . . . . . . . . . . . . . . . . . . . . . . . . . .25

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25

ISOLATION PANEL COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

Isolation Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

Circuit Breaker Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Enclosures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Installation Convenience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

OPERATING ROOM PANELS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Wiring Diagrams and Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

INTENSIVE CARE/CORONARY CARE PANELS . . . . . . . . . . . . . . . . . .30

Wiring Diagrams and Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

DUAL OUTPUT VOLTAGE ISOLATION PANELS . . . . . . . . . . . . . . . . . .32

Transformers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

Contents

Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33

Catalog Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

Interior Catalog Number Selections . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Transformer Catalog Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Back Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

DUPLEX ISOLATION PANELS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Wiring Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

THREE-PHASE ISOLATION PANELS . . . . . . . . . . . . . . . . . . . . . . . . . . .38

Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-40

X-RAY PANELS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Wiring Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Combination X-Ray Receptacle (XR-IAI) With Indicator Module . . . . .42

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Supervisory Module For X-Ray Panel (8CI-IAI) . . . . . . . . . . . . . . . . . .42

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

PANEL-MOUNTED INDICATOR ALARMS . . . . . . . . . . . . . . . . . . . . . . . .43

ORIC-A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43

ORIC-AC and ORIC-A5C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43

POWER/GROUND MODULES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

Power/Ground Modules (To Fit Gang Boxes) . . . . . . . . . . . . . . . . . . .45

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Master Grounding Station Module . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

Ground Modules. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

Ground Cord Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

REMOTE INDICATOR ALARMS AND ANNUNCIATORS . . . . . . . . . . . .47

Remote Indicator Alarm (IA-1C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Indicator and Milliammeter Module (M5-IAI) . . . . . . . . . . . . . . . . . . . .48

Annunciator Panel For 1 To 4 Circuits . . . . . . . . . . . . . . . . . . . . . . . . .48

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

Annunciator Panel For 5 To 8 Circuits . . . . . . . . . . . . . . . . . . . . . . . . .49

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

Annunciator Panel For 9 To 12 Circuits . . . . . . . . . . . . . . . . . . . . . . . .49

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

Annunciator Panel For 13 To 16 Circuits . . . . . . . . . . . . . . . . . . . . . . .50

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50

ISO-GARD

LINE ISOLATION MONITOR . . . . . . . . . . . . . . . . . . . . . . . .51

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

DIGITAL CLOCKS, TIMERS, AND ACCESSORIES . . . . . . . . . . . . . . . .52

MCT Series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52

Accessory Control Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52

Dual Display Clock/Timer (MCT-12B) . . . . . . . . . . . . . . . . . . . . . . . . .53

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

Control Panel (MCT-CT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

Surgical Chronometer (MCT-14B) . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

Control Panel (MCT-4RC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

Accessory Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55

Battery Pack (MCT-BP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55

Trim Plate (MCT-95135) and Back Box (53007BB) . . . . . . . . . . . .55

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General Information and Application

Overview and History

OVERVIEW

This bulletin has three purposes:

• To demonstrate to hospitals the need for isolated systems

• To guide the engineer in the application of hospital ungrounded systems

• To describe in detail the Square D equipment used to design effective and economical isolated ungrounded systems

Square D has been building isolating transformers for hospital use since the ﬁrst equipment standards appeared in 1944. We have built an enviable reputation for reliability, low sound levels , and minimum inherent leakage.

Proof of the engineered superiority of Square D products is found throughout the country in numerous installations, many dating to the earliest applications of isolating transformers.

This bulletin is not intended as a “do it yourself” manual for installation of hospital isolated systems. The information contained here regarding codes and standards is current as of this writing. However, these codes and standards are continually changing and are also subject to local changes and interpretations.

Any hospital considering design changes to electrical systems in critical care patient areas should obtain the services of an electrical consulting engineer. The technical complexities of today’s hospitals dictate that all involved parties have a thorough understanding of the hospital’s objectives. This is the only way to avoid purchasing unnecessary equipment.

Time spent planning the changes will result in large dividends, provided the following parties are involved:

• Consulting engineer

• Hospital administrator

• Hospital engineer

• Chief of surgery

• Chief of anesthesiology

• Cardiologist

• Manufacturer’s representative

HISTORY

During the 1920s and ’30s, the number of ﬁres and explosions in operating rooms grew at an alarming rate. Authorities determined that the major causes of these accidents fell into two categories:

• Man-made electricity

• Static electricity (75% of recorded incidents)

In 1939, experts began studying these conditions in an attempt to produce a safety standard. The advent of W orld W ar II dela y ed the study’ s results until 1944. At that time, the National Fire Protection Agency (NFPA) published “Safe Practices in Hospital Operating Rooms.”

The early standards were not generally adopted in new hospital construction until 1947. It soon became apparent that these initial standards fell short of providing the necessary guidelines for construction of rooms in which combustible agents would be used.

NFPA appointed a committee to revise the 1944 standards. In 1949, this committee published a new standard, NFPA No. 56, the basis for our current standards.

The National Electrical Code (NEC) of 1959 ﬁrmly established the need for ungrounded isolated distribution systems in areas where combustible gases are used.

In the same year, the NEC incorporated the NFPA standards into the code. The NFPA No. 56A– Standard for the Use of Inhalation Anesthetics, received major revisions in 1970, 1971, 1973, and 1978.

In 1982, NFPA No. 56A was incorporated into a new standard, NFPA No. 99—Health Care Facilities. The new document includes the text of several other documents, such as:

• NFPA-3M • 56HM

• 56K • 56B

• 76A • 56C

• 76B • 56D

• 76 • 56G

The material originally covered by NFPA 56A is now located in Chapter 3 of NFPA No. 99. NFPA No. 99 was updated in 1984, 1987, 1990, 1993 and 1996.

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General Information and Application

Electrical Hazards

The increased use of electronic diagnostic and treatment equipment, and the corresponding increase in electrical hazards, has resulted in the use of isolated ungrounded systems in new areas of the hospital since 1971. These new hazards were ﬁrst recognized in NFPA bulletin No. 76BM, published in 1971. Isolating systems are now commonly used for protection against electrical shock in many areas, among them:

• Intensive care units (ICUs)

• Coronary care units (CCUs)

• Emergency departments

• Special procedure rooms

• Cardiovascular laboratories

• Dialysis units

• Various wet locations

ELECTRICAL HAZARDS IN HOSPITALS

The major contributors to hospital electrical accidents are faulty equipment and wiring. Electrical accidents fall into three categories:

• Fires

• Burns

• Shock

This section covers the subject of electrical shock. Electrical shock is produced by current, not

voltage. It is not the amount of v oltage a person is exposed to, but rather the amount of current transmitted through the person’s body, that determines the intensity of a shock. The human body acts as a large resistor to current ﬂow. The average adult exhibits a resistance between 100,000 ohms (Ω) and 1,000,000 Ω, measured hand to hand. The resistance depends on the body mass and moisture content.

The threshold of perception for an average adult is 1 milliampere (mA). This amount of current will produce a slight tingling feeling through the ﬁngertips.

Between 10 and 20 mA, the person experiences muscle contractions and ﬁnds it more difﬁcult to release his or her hand from an electrode.

The hazardous levels of current f or many patients are amazingly smaller. The most susceptible patient is the one exposed to externalized conductors, diagnostic catheters, or other electric contact to or near the heart.

Surgical techniques bypass the patient’s body resistance and expose the patient to electrical current from surrounding equipment. The highest risk is to patients undergoing surgery within the thoracic cavity. Increased use of such equipment as heart monitors, dye injectors, and cardiac catheters increases the threat of electrocution when used within the circulatory system.

Other factors contributing to electrical susceptibility are patients with hypokalemia, acidosis, elevated catecholamine levels, hypoxemia, and the presence of digitalis. Adult patients with cardiac arrhythmias can be electrocuted through the misuse of pacemakers connected directly to the myocardium.

Infants are more susceptible to electric shock because of their smaller mass, and thus lower body resistance. Much has been written about current levels considered lethal for catheterized and surgical patients. Considerable controversy exists about the actual danger level for a patient who has a direct electrical connection to his or her heart. The minimum claimed hazard level seems to be 10 microamperes (µA) with a maximum level given at 180 µA. Whatever the correct level, between 10 and 180 µA, it is still only a fraction of the level that is hazardous to medical attendants serving the patient.

It is believed that approximately 1,000 Ω of resistance lies between the patient’s heart and external body parts.

All of this information leads us to the conclusion that the patient environment is a prime target for electrical accidents. Nowhere else can one ﬁnd these elements: lowered body resistance, more electrical equipment, and conductors such as blood, urine, saline, and water. The combination of these elements presents a challenge to increase electrical safety.

An externally applied current of 50 mA causes pain, possibly fainting, and exhaustion.

An increase to 100 mA will cause ventricular ﬁbrillation.

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Neglect to Connect

Ground Wire of Adapter

Frayed Power Cord

2-Wire Extension Cord

Misuse of 3-Prong Plug

with 2-Wire Extension Cord

Figure 2 Electrical Hazards

General Information and Application

Electrical Hazards

Leakage Currents

Electric equipment operating in the patient vicinity , even though operating perfectly, may still be hazardous to the patient. This is because every piece of electrical equipment produces a leakage current. The leakage consists of any current, including capacitively coupled current, not intended to be applied to a patient, but which may pass from exposed metal parts of an appliance to ground or to other accessible parts of an appliance.

Normally, this current is shunted around the patient via the ground conductor in the power cord. However, as this current increases, it can become a hazard to the patient.

Isolated systems are now commonly used to protect against electrical shock in many areas, among them:

• Intensive care units (ICUs)

• Coronary care units (CCUs)

• Emergency departments

• Special procedure rooms

• Cardiovascular laboratories

• Dialysis units

• Various wet locations

Without proper use of grounding, leakage currents could reach values of 1,000 µA before the problem is perceived. On the other hand, a leakage current of 10 to 180 µA can injure the patient. Ventricular ﬁbrillation can occur from exposure to this leakage current.

Figure 1 illustrates the origin and path of leakage current.

Failure to use the grounding conductor in power cords causes a dangerous electrical hazard. This commonly results from using two-prong plugs and receptacles, improper use of adapters, use of twowire extension cords, and the use of damaged electrical cords or plugs. Figure 2 illustrates these hazards.

Answers

There are no perfect electrical systems or infallible equipment to eliminate hospital electrical accidents. However, careful planning on the part of the consulting engineer, architect, contractor, and hospital personnel can reduce electrical hazards to nearly zero. Hospital electrical equipment receives much physical abuse; therefore, it must be properly maintained to provide electrical safety for patients and staff.

Procedures for electrical safety should include the following:

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Path of Leakage Current

AC Power Line

Leakage Current In

AC Power Line

Ground Wire

Power Cord

Figure 1 Origin of Leakage Current

Instrument Cases

Electric Circuit

Leakage Current In Power Transformer

• Check all wall power receptacles and their polarities regularly.

• Routinely verify that conductive surfaces are grounded in all patient areas.

• Request that patient electrical devices such as toothbrushes and shavers be battery powered.

• Use completely sealed and insulated remote controls for use in patient beds.

• Use bedrails made of plastic or covered in insulating material.

General Information and Application

Codes and Standards

CODES AND STANDARDS

It would not be practical to attempt to reproduce the codes and standards that affect the application of isolated distribution systems in hospitals. As was previously mentioned, codes are continually reﬁned and updated, with frequent amendments between major publications. All hospitals should have copies of the current standards for reference; the design engineer

must

have this information available. Obtain copies of all standards referenced in this bulletin from the National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.

This chapter brieﬂy covers the sections of codes and standards that apply to hospital isolated ungrounded distribution systems. This chapter only covers a few of the important points within these standards. A thorough study of applicable codes and standards is required to effectively design a project.

NFPA No. 99

History

Published by the NFPA, this code is included as a reference in the NEC Article 517.

NFPA No. 99 addresses ﬁre, explosion, and electrical safety in hospitals. It consolidates 12 individual NFPA documents or standards into one document.

Many hospitals and consulting engineers are unaware of this document and its requirements. Square D recommends that all consulting engineers who design hospitals have the hardcover “handbook” version of this document available.

Anesthetizing Location Classiﬁcations

The ﬁrst type of location is that which is ﬂammable because explosive anesthesia is used. This location must be designed to comply with NEC Article 501.

There are many other requirements for the ﬂammable anesthetizing locations; these requirements are discussed in Chapter 12 of NFPA No. 99. Explosive anesthesia is now virtually non-existent in the United States. Therefore, this handbook does not cover the ﬂammable location in any detail.

Non-ﬂammable anesthetizing location requirements are also covered in Chapter 12 of NFPA No. 99. A permanent sign must be displayed at the entrance to all ﬂammable locations. It must state that only non-ﬂammable anesthetics can be used in the room.

Non-ﬂammable anesthetizing locations can be further divided into locations that are subject to becoming wet and those that are not. A wet location requires special protection against electrical shock. The allowable protection is as follows:

• Ground-fault circuit interrupter if ﬁrst-fault conditions are to be allowed to interrupt power

• Isolated power system if ﬁrst-fault conditions are not to be allowed to interrupt power

The governing body of the hospital will make the determination of a “wet location,” using the following deﬁnition:

A patient care area that is normally subject to wet conditions while patients are present. This includes standing ﬂuids on the ﬂoor or drenching of the work area, either of which condition is intimate to the patient or staff. Routine housekeeping procedures and incidental spillage of liquids do not deﬁne a wet location.

NFP A No . 99 deﬁnes the items in an anesthetizing location, which must be powered from the isolated ungrounded system. Because this section is subject to individual interpretation by local Code authorities, work closely with these authorities before selecting the equipment to be powered from standard grounded systems. This is especially important when ordering permanently installed equipment, such as X-ray apparatus. NFPA No. 99 and the NEC Article 517 allow the grounded circuit providing power to an isolated system to enter the non-hazardous area of an anesthetizing location. However, ungrounded wiring and grounded service wiring cannot occupy the same conduit or raceway.

The primary and secondary of the isolation transformer cannot exceed 600 volts (V) in any isolation system that supplies power to an anesthetizing area or other critical care patient area. The secondary circuit conductors must be provided with an approved overcurrent protective device in both conductors of each branch circuit.

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Square D 4800 User manual

Specifications and Main Features

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User Manual