GE Ohmeda Serv O2 User manual

ServO

Oxygen Control System

Operation, Maintenance & Service Manual

erv

Oxygen Control System

Oxygen

(V/V)

™

+ -

Alarms

High

Defect

Low

Sensor

Enable

Battery

Enable

Oxygen

Set

Incubator Headbox

Calibrate

User Responsibility

This Product will perform in conformity with the description thereof contained in this operating manual and accompanying labels and/or inserts, when assembled, operated, maintained and repaired in accordance with the instructions provided. This Product must be checked periodically. A defective Product should not be used. Parts that are broken, missing, plainly worn, distorted or contaminated should be replaced immediately. Should such repair or replacement become necessary, Ohmeda recommends that a telephone or written request for service advice be made to the nearest Ohmeda Regional Service Center. This Product or any of its parts should not be repaired other than in accordance with written instructions provided by Ohmeda and by Ohmeda trained personnel. The Product must not be altered without the prior written approval of Ohmeda’s Quality Assurance Department. The user of this Product shall have the sole responsibility for any malfunction which results from improper use, faulty maintenance, improper repair, damage, or alteration by anyone other than Ohmeda.

CAUTION w U.S Federal and Canadian law restrict this device to sale by or on the order of a

licensed medical practitioner.

Table of Contents

General Precautions

Warnings........................................................................................................................ iii

Cautions..........................................................................................................................v

1/General Information

Introducing the ServO2 Oxygen Control System .........................................................1-1

Oxygen Environment ...................................................................................................1-1

Control Panel ...............................................................................................................1-2

Controls...............................................................................................................1-2

Displays...............................................................................................................1-3

Alarms .................................................................................................................1-3

Low Cell Indicator ........................................................................................................1-4

Operating Modes .........................................................................................................1-4

Mounting Options.........................................................................................................1-5

2/Operation

Preoperative Checkout Procedure...............................................................................2-1

Set-Up..........................................................................................................................2-2

Calibration....................................................................................................................2-3

Calibration Schedule ...........................................................................................2-3

Calibration Procedure .........................................................................................2-3

Using the ServO2 Oxygen Control System ..................................................................2-5

Incubator mounting bracket .........................................................................................2-6

Mounting the sensor............................................................................................2-6

Assembly.............................................................................................................2-7

Disassembly........................................................................................................2-8

3/Maintaining the ServO2 Oxygen Control System

Cleaning.......................................................................................................................3-1

4/Service procedures

4.1 Repair Policy..........................................................................................................4-2

4.2 Maintenance schedule..........................................................................................4-2

4.3 Troubleshooting .....................................................................................................4-3

4.4 Repair Procedures.................................................................................................4-4

4.5 Service Calibration...............................................................................................4-11

4.6 Service Checkout Procedure ...............................................................................4-14

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Table of Contents

5/Illustrated parts

Exterior parts ...............................................................................................................5-1

Base, manifold and solenoid parts...............................................................................5-2

Interior parts.................................................................................................................5-3

Sensor mounting bracket.............................................................................................5-4

Service Kits..................................................................................................................5-4

Complete units.............................................................................................................5-4

6/Schematics

Pneumatic diagram......................................................................................................6-1

Control board schematic..............................................................................................6-2

Control and PSU board layout .....................................................................................6-4

PSU board schematic ..................................................................................................6-5

Display board schematic..............................................................................................6-6

Display board layout ....................................................................................................6-7

Appendix

Warranty

Specifications.............................................................................................................. A-1

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General Precautions

Table of Contents

Definitions

What the attention symbol means

Next to each warning or caution, we have placed an “attention, readaccompanying documents” symbol to alert you to the presence of these important statements. This is the attention symbol:

When the attention symbol appears in front of text that is printed on the system itself, it means that the text is elaborated upon in the operation manual.

WARNING: A Warning statement is used when the possibility of injury to the patient or the operator exists.

CAUTION: A Caution statement is used when the possibility of damage to the equipment exists.

~ Indicates alternating current.

m Indicates IEC Type BF equipment.

Important: An Important statement is similar to a note but is used for greater emphasis. Note: A Note provided additional information to clarify a point in the text.

The following are general Warnings and Cautions. Precautions specific to certain procedures are found in the text of the manual.

w W arnings

Before using the ServO2 Oxygen Control System, read through this entire manual. As with all medical equipment, attempting to use this device without a thorough understanding of its operation may result in patient or user injury.

Always disconnect the power and gas supplies before performing service or maintenance procedures detailed in this manual. Apply power only if you are specifically instructed to do so as part of the procedure.

Indicates drip proof as stipulated in BS5724/IEC 601-1.

Indicates Class II equipment: earth connection not required for protection against shock. Protection is provided by the inclusion of double and/or increased insulation. When servicing use only identical replacement parts.

iii

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iii

General Precautions

Table of Contents

Oxygen concentrations higher than 40% can increase the risk of retrolental fibroplasia (retinopathy of prematurity). It is probable that even concentrations of 40% or less oxygen (formerly considered safe) could be dangerous to some infants. Therefore, arterial blood gas measurements are extremely important for regulation of the concentration of inspired oxygen when an oxygen-enriched environment is considered necessary. (See current edition of “Standards and Recommendations for Hospital Care of Newborn Infants” prepared by the Committee of Fetus and Newborn of the Academy of Pediatrics.)

Complete the “Preoperative Check-out ” section of this manual before putting the unit into operation. If the ServO2 Oxygen Control System fails any portion of the checkout procedure it must be removed from use and repaired.

To prevent the possible depletion of the oxygen supply, disconnect the ServoO Oxygen Control System from gas supplies when not in use.

Do not use the ServO2 Oxygen Control System in the presence of flammable anesthetics; an explosion hazard exists under these conditions.

Do not use oil bearing materials on or near the pneumatic parts of this unit. Oils and grease oxidize readily, and in the presence of oxygen, they will burn violently. The air or oxygen parts must be discarded if they are contaminated with oil or grease.

Fire hazard! Even material that will not normally burn will ignite readily and burn rapidly in high concentrations of oxygen. Keep all sources of ignition away from the incubator or headbox. Display “NO SMOKING” signs prominently.

Spontaneous and violent ignition may occur if oil, grease or greasy substances come in contact with oxygen under pressure. Keep oil and grease away from regulators, cylinder valves, tubing and connections, and all other oxygen equipment.

Use only approved reducing or regulating valves marked for oxygen service on high pressure oxygen cylinders. Do not use valves for air or gases other than oxygen, since they may be hazardous when returned to oxygen service. Operate all oxygen equipment strictly in accordance with the manufacturer’s directions.

High pressure oxygen and medical air equipment should always be located outside of the nursery. Securely fix cylinders in place so that they can not be knocked over while in use. Locate cylinders as far from the incubator or headbox as possible.

Use only equipment designed for use in hazardous locations in delivery rooms. Mixtures of oxygen and flammable vapors, such as alcohol, ether, ethylene and cyclopropane may explode if ignited. Electrical static spark discharges or high temperature surfaces, in addition to all other more common sources of ignition, may ignite these mixtures. Refer to Article 517 of the National Electrical Code, ANSI/NFPA 70, for the use of flammable anesthetics.

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General Precautions

Table of Contents

Cautions

Only competent individuals trained in the repair of this equipment should attempt to service it as detailed in the Manual.

Detailed information for more extensive repairs is included in the service manual solely for the convenience of users having proper knowledge, tools and test equipment, and for service representatives trained by Ohmeda.

Precautions specific to certain procedures are found in the text of the manual.

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Notes

Table of Contents

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1/General Information

In this section

Introducing the ServO2 Oxygen Control System ....................................................... 1-1

Oxygen environment.................................................................................................. 1-1

Control Panel ............................................................................................................. 1-2

Controls............................................................................................................. 1-2

Displays............................................................................................................. 1-3

Alarms ............................................................................................................... 1-3

Operating Modes............................................................................................... 1-4

Mounting options............................................................................................... 1-5

Introducing the ServO2 Oxygen Control System

The ServO2 oxygen control system controls a patient’s oxygen environment. By automatically changing the delivered gas ratio, it maintains the oxygen concentration level set by the clinician.

A comprehensive series of alarms include high and low oxygen concentration, sensor disconnected, short circuit or failure, battery running low and internal malfunction. The system has two modes of operation which allow it to be used with both incubators and head boxes.

Oxygen Environment

The ServO2 oxygen control system has a finite flow capacity. If the rate of escape from the patient enclosure exceeds this flow, the unit will be unable to maintain the specified concentration and will indicate a low oxygen alarm condition. Therefore sealing the enclosure at high oxygen concentration levels is important.

When the enclosure is opened, oxygen concentration levels rapidly deplete. To react to such a situation, the ServO2 system uses an oxygen boost system to quickly return the environment to the specified level. The boost automatically turns on when demand is highest, and turns off when the actual concentration level nears the specified level. (It is important to point out that with the unit at its highest setting and the chamber leaking at the greatest possible rate, it would take approximately 26 minutes to deplete a full Etype cylinder.)

In most cases, the ServO2 will control oxygen concentration levels within incubators or similar large enclosures, and allows the nursing staff to dispense with headboxes. This reduces the number of changes in oxygen concentration that the patient would experience with the removal of its headbox. It also improves O2 stabilization in headboxes/ beds when incubators are not available or clinically indicated.

1-1

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1-1

1/General Information

Control Panel

Figure 1-1

Control Panel

Oxygen Control System

erv

888

+ -

Alarms

High

Low

Oxygen (V/V)

Defect Sensor

Low Battery

Enable

Calibrate

Oxygen Set

Controls

On/Stand by button. Press to turn unit on. Press again to turn unit off. A short delay has

been set into the ‘off’ function to avoid inadvertent switch-off.

Enable

Calibrate

Note: The On/Stand by button does not control the electrical power supply. Whenever the ServO2 system power cord is connected the internal battery is being charged.

Enable button. Used in conjunction with the M or ? buttons to change the required oxygen concentration level.

Calibrate button. Used to check that the unit is within calibration. When the Calibrate button is pressed, the ServO2 system automatically delivers 100% oxygen to the output tube and the Oxygen Set display goes blank. You must press the Calibrate button and the

M or ? buttons to change the calibration setting.

M & ? buttons. Used with Calibrate and Enable buttons to change the calibration and

Oxygen Set point. Pressing the button changes the display by one digit. Holding the button in continuously changes the display one digit at a time.

Alarm silence button. Cancels the audible alarm on High O2, Low O2, and Low Battery alarms for a period of approximately 2 minutes, but the alarm indicator remains on. Sensor and Defect alarms cannot be silenced.

1-2

At the end of the alarm silence period the audible alarm will automatically resume if the alarm condition has not been resolved.

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1-2

1/General Information

Displays

% Oxygen (V/V) display. Three digit display indicates the actual oxygen concentration

Oxygen

level monitored by the oxygen sensor. This is displayed as a percentage of oxygen by

888

(V/V)

volume(v/v).

Alarms

High

Low

+ -

Oxygen Set

Defect Sensor

% Oxygen Set display. Two digit display indicates the required oxygen concentration level set by the clinician. This is displayed as a percentage of oxygen by volume (v/v). When the environment is stable the Oxygen Set and Oxygen V/V displays should be within one digit of each other.

Battery indicator. When on indicates that the ServO2 system is running from its internal battery.

Line indicator. When on indicates that the ServO2 system is using power from the wall outlet. This is the normal mode of operation. This also indicates that the internal battery is being automatically recharged.

Alarms

High alarm indicator. Actual Oxygen concentration level is greater than 3% (v/v) above

that displayed on Oxygen Set. Alarm condition immediately lights the High indicator on the front panel. After a delay period of 2 minutes (nominal) an audible alarm sounds. Both the visual indicator and audible alarm will automatically reset when the alarm condition is resolved.

Low alarm indicator. Actual oxygen concentration level is greater than 3% (v/v) below that displayed on Oxygen Set. Alarm condition immediately lights the Low indicator on the front

Low

panel. After a delay period of 2 minutes (nominal) an audible alarm sounds. Both the visual

Battery

indicator and audible alarm will automatically reset when the alarm condition is resolved. Immediately following first pressing the On/Stand by button the Low audible alarm is

deactivated for approximately 2 minutes. This allows time for the gases to fill larger chambers such as incubators, avoiding unnecessary alarms.

Sensor alarm indicator. The oxygen sensor is disconnected or there is an open or short circuit in the sensor wiring. The indicator lights and the alarm sounds immediately, and cannot be silenced. The % Oxygen display reads “00” and the oxygen solenoid is automatically disabled.

Defect alarm indicator. Internal malfunction causes the indicator to light and the alarm to sound immediately. This alarm cannot be silenced. Oxygen supply is automatically disabled for safety purposes.

WARNING w Do not use the ServO2 Oxygen Control System if a Defect alarm is indi-

cated. The unit must be immediately removed from use and repaired.

Low Battery alarm indicator. Indicator lights immediately when the battery has only

7 minutes (nominal) remaining life. Delay of 2 minutes before the audible alarm sounds. The audible alarm can be silenced.

1-3

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1/General Information

WARNING w If the low battery alarm remains unattended for a period of 7 minutes the

ServO2 Oxygen Control System will automatically turn itself off to prevent permanent battery damage. The internal battery is provided as an emergency back-up only.

Mode key and holder

% Oxygen Set

Actual % Oxygen

On/Off button

Battery indicator

Line indicator

Alarm Silence button

Mode indicator

Figure 1-2

ServO2 Oxygen Control System front view

+ -

Incubator Headbox

Alarm indicators

Enable buttons

erv

Oxygen Control System

Alarms

High

Low

Oxygen

(V/V)

Oxygen

Set

Defect

Sensor

Enable

Low

Enable

Battery

Calibrate

Calibration Port

Input barb connector

Sensor connector

% Oxygen control buttons

Calibrate button

Operating Modes

The ServO2 system can work in either Incubator or Headbox mode. Incubator mode. To put the unit in Incubator mode press the metal switch on the back

of the unit (see Figure 1-3) and insert mode key into the slots . When connected to an oxygen or air supply, the mode indicator on the lower left front of the unit will show a series of red dots to indicate the Incubator mode.

Headbox mode. With the mode key removed (default) the unit is in low flow or headbox mode. The mode indicator on the lower left front of the unit will show a series of black dots (see Figure 1-2).

To put the unit back into Headbox mode simply remove the mode key. A holder located on the top of the unit is provided for the safe storage of the mode key.

1-4

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1-4

1/General Information

Medical air inlet

Oxygen inlet

Gas outlet

Headbox/Incubator switch

Power cord input

Fuse holder

Figure 1-3

ServO2 Oxygen Control System rear view

Mounting options

CAUTION w It is recommended that the ServO2 Oxygen Control System be used in con-

junction with a mounting bracket to prevent the unit from falling and being damaged.

There are two mounting options available:

Dovetail mounting bracket (fits rails used on Ohmeda equipment) ......... 6600-0236-910

C-clamp/Universal rail mounting bracket (fits European style rails) ........ 6600-0236-913

1-5

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1-5

Notes

1/General Information

1-6

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1-6

2/Operation

WARNINGS w Do not perform the preoperative checkout procedure when the unit is

being used with a patient.

w Complete the “Preoperative Checkout ” section of this manual before

putting the unit into operation. If the ServO2 Oxygen Control System fails any portion of the checkout procedure it must be removed from use and repaired.

w Oxygen concentrations higher than 40% can increase the risk of

retrolental fibroplasia (retinopathy of prematurity). It is probable that even concentrations of 40% or less oxygen (formerly considered safe) could be dangerous to some infants. Therefore, arterial blood gas measurements are extremely important for regulation of the concentration of inspired oxygen when an oxygen-enriched environment is considered necessary. (See current edition of “Standards and Recommendations for Hospital Care of Newborn Infants” prepared by the Committee of Fetus and Newborn of the Academy of Pediatrics.)

w Do not use oil or oil bearing materials on or near the pneumatic parts of

this unit. Oils and grease oxidize readily, and in the presence of oxygen, they will burn violently. The air and oxygen parts must be discarded if they are contaminated with oil or grease.

In this section

Preoperative checkout Procedure ............................................................................. 2-1

Set-Up........................................................................................................................ 2-2

Calibration.................................................................................................................. 2-2

Calibration Schedule ......................................................................................... 2-2

Calibration Procedure ....................................................................................... 2-3

Using the ServO2 Oxygen Control System ................................................................ 2-3

Preoperative checkout procedure

1. Visually inspect the ServO2 Oxygen Control System, its power cord and sensor

cable for signs of damage.

2. Connect an oxygen supply to the unit, ensuring correct gas connection if no cross

connection system is in use such as DISS or NIST. Turn the unit on and check that gas exhausts from the outlet barb on the back of the unit. Disconnect the oxygen supply.

2-1

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2-1

2/Operation

3. Repeat step 2 with an air supply connected to the ServO2 Oxygen Control System.

4. Connect both gas supplies to the unit. Turn the unit on. Press the mode switch on

5. Disconnect the sensor to verify that the sensor indicator lights and that the alarm

6. Unplug the unit's power cord and verify that the battery indicator lights and that the

7. Calibrate the unit according to the instructions in Calibration in this section.

Set-up

1. Connect the Sensor cable to ServO2 Oxygen Control System.

2. Install the appropriate air and oxygen connections to the 1/8" NPT fittings on the

the back of the unit and check that the flow rate increases (there will be an audible difference in sound level). When the mode switch is depressed and the unit is connected to a gas supply, check that the mode indicator on the front of the unit shows red dots.

sounds. Reconnect the sensor and verify the alarm is silenced and the indicator goes out.

unit continues to function on battery power.

back of the unit.

3. Connect oxygen and air supplies to the inlets on the back of the unit (See Figure

1-3). Gas supplies greater than 65 PSI require high pressure ServO2 units (see page 5-4 in section 5/Illustrated Parts).

4. Plug the power cord into the wall outlet. Check that the Line indicator is lit on the

front panel (See Figure 1-1).

5. Connect an appropriate length of tubing to the output connector at the rear of the

device (See Figure 1-3).

6. Place the unit within 6 feet (2 meters) of the incubator/cot to keep the sensor cable

from being strained.

CAUTION w It is recommend that the ServO2 Oxygen Control System be used in conjunction

with a mounting bracket to prevent the unit from falling and being damaged.

Calibration

Calibration Schedule

Calibrate the ServO2 system and its integral oxygen sensor according to the following schedule:

• Before the equipment is first put into use.

2-2

• Before the equipment is used immediately following an extended period of storage.

• Once every 24 hours when the ServO2 system is in constant use.

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2-2

2/Operation

Calibration Procedure

1. Place oxygen sensor securely into the calibration port .

2. Fit the distal end of the ServO2 output hose (the end farthest away from the unit)

3. Press and hold the Calibrate button on the control panel. This will automatically

4. Allow approximately 20 seconds for the environment and sensor to stabilize.

5. While still pressing the Calibrate button, adjust the “% Oxygen (V/V)” display to

6. When the display stabilizes at 100%, release all the buttons. Remove the sensor

7. Remove the output hose from the calibration port input barb and place it in the

securely over the input barb connector on the calibration port.

blank out the “% Oxygen Set” display and deliver 100% Oxygen through the output hose. Press and hold the Calibrate button throughout the calibration procedure.

read 100% by pressing the M or ? button. If it does not read 100%, the sensor must be replaced.

from the port and place it in the ambient air. Check that the “% Oxygen (V/V)” display reads 21% (± 1%). If it does not, the sensor must be replaced.

enclosure.

If a calibration port is not available the following is an alternative way to calibrate the unit.

1. Place oxygen sensor and the output tube from the ServO2 system together in a

small container such as a plastic bag.

CAUTION w Do not totally seal the container - excessive pressure may develop which can

lead to incorrect calibration. Always use the gas output from the ServO2 Oxygen Control System to calibrate the unit.

2. Press and hold the Calibration button on the front panel. This will automatically

blank out the % Oxygen Set display, and deliver 100% oxygen through the output tube. Hold in the Calibration button throughout the calibration procedure.

3. Allow approximately 20 seconds for the environment and sensor to stabilize.

4. While still pressing the Calibration button, adjust the % Oxygen V/V display to read

100% by pressing either the M or ? button.

5. Release all buttons. Remove sensor from container and place in ambient air away

from the delivery tube. Check % Oxygen (v/v) display now reads 21% (±1%). Note: If the display cannot be adjusted to reach 100% or does not return to 21%

(±1%), then the sensor must be replaced.

Using the ServO2 Oxygen Control System

WARNINGS w Fire hazard! Even material that will not normally burn will ignite readily

and burn rapidly in high concentrations of oxygen. Keep all sources of ignition away from the incubator or headbox. Display “NO SMOKING” signs prominently.

2-3

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