Welch Allyn CP50 ECG User manual

™

CP 50

and CP 50 Plus
12-lead resting
electrocardiograph

™

Directions for use

ii Welch Allyn CP 50 resting electrocardiograph

© 2009 Welch Allyn, Inc. All rights are reserved. No one is permitted to reproduce or duplicate, in any form, this manual or any part
thereof without permission from Welch Allyn.

Caution: Federal US law restricts sale of the device identified in this manual to, or on the order of, a licensed physician.

Welch Allyn assumes no responsibility for any injury, or for any illegal or improper use of the product, that may result from failure to
use this product in accordance with the instructions, cautions, warnings, or indications for use published in this manual.

Welch Allyn is a registered trademark of Welch Allyn, Inc. CP 50, CP 50 Plus, and CardioPerfect are trademarks of Welch Allyn, Inc.

PDI and Sani-Cloth are registered trademarks of PDI, Inc. CaviWipes is a trademark of Metrex Research Corporation.

Software in this product is copyright Welch Allyn or its vendors. All rights are reserved. The software is protected by United States of
America copyright laws and international treaty provisions applicable worldwide. Under such laws, the licensee is entitled to use the
copy of the software incorporated within this instrument as intended in the operation of the product in which it is embedded. The
software may not be copied, decompiled, reverse-engineered, disassembled or otherwise reduced to human-perceivable form. This
is not a sale of the software or any copy of the software; all right, title and ownership of the software remains with Welch Allyn or its
vendors.

Welch Allyn Technical Support

European Customer Care + 35 3 46 906 7790 France + 33 155 69 58 49

Germany + 49 6950 985 132 China + 86 21 6327 9631

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Malaysia + 60 3 7875 3341 Sweden + 46 858 536 551

United Kingdom [phone] Australia + 61 2 9638 3000

Multilanguage CD: 102731

This manual: 80015344, B

Welch Allyn Ltd
Navan Business Park
Dublin Road, Navan
County Meath, Republic of Ireland

www.welchallyn.com

Contents

1 - Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

iii

About this document . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Intended use. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Indications for use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

About the test types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Controls, indicators, and connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

General warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

General cautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2 - Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Connecting the patient cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Loading the thermal paper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Powering the electrocardiograph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

About the menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Viewing or changing the settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Viewing the device information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Verifying proper operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Connecting to an external USB printer (optional, CP 50 Plus only). . . . . . . . . . . 18

Connecting to a CardioPerfect workstation

(optional, CP 50 Plus only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

3 - ECG testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Attaching the leads to the patient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Electrode locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Performing an ECG test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

4 - Administrative tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Turning the security option on or off (CP 50 Plus only). . . . . . . . . . . . . . . . . . . . 27

Managing the user list (CP 50 Plus only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Turning the audit trail on or off (CP 50 Plus only) . . . . . . . . . . . . . . . . . . . . . . . . 28

Managing the worklist (CP 50 Plus only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Managing the test directory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

5 - Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Cleaning the equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Inspecting the equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Testing the electrocardiograph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Replacing the battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Replacing the AC fuses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Storing the equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Discarding the equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

6 - Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Limited warranty. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Service policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

iv Contents Welch Allyn CP 50 resting electrocardiograph

A - Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

B - EMC guidance and manufacturer’s declarations . . . . . . . . . . . . . . 43

1

1

Introduction

About this document

This document is written for clinical professionals with a working knowledge of medical
procedures and terminology required for monitoring cardiac patients.

Before using the electrocardiograph for clinical applications — or before setting up,
configuring, troubleshooting, or servicing the electrocardiograph — you must read and
understand this document and all other information that accompanies the
electrocardiograph and related options or accessories.

Intended use

The Welch Allyn electrocardiography products (subject devices) are intended for use by
trained operators in health facilities. The subject devices provide the following diagnostic
functions:

• Acquiring, viewing, storing, and printing ECG waveforms using ECG front-end
modules (patient cables) and associated accessories that provide signal acquisition for
up to twelve (12) leads of patient ECG waveforms through surface electrodes adhered
to the body.

• Using optional algorithms to generate measurements, data presentations, graphical
presentations, and interpretative statements on an advisory basis. These are
presented for review and interpretation by the clinician based upon knowledge of the
patient, the result of physical examination, the ECG tracings, and other clinical
findings.

Indications for use

The electrocardiograph is one of the tools that clinicians use to evaluate, diagnose, and
monitor patient cardiac function.

The 12-lead ECG interpretive algorithm provides a computer-generated analysis of
potential patient cardiac abnormalities which must be confirmed by a physician with other
relevant clinical information.

2 Introduction Welch Allyn CP 50 resting electrocardiograph

A

B
C

D
E

H

G

F

About the test types

Auto ECG A report typically showing a 10-second acquisition of 12 leads of ECG

information combined with patient data, measurements, and optional interpretation.
Auto ECGs can be saved to the electrocardiograph’s test directory or to a USB mass­storage device. In CP 50 Plus models, auto ECGs can also be sent to a Welch Allyn
CardioPerfect workstation.

Stat ECG An auto ECG that starts instantly without waiting for you to enter patient data

or adjust the waveforms.

Rhythm ECG A continuous, real-time printout of rhythm strips with a user-defined lead

configuration. Rhythm ECGs are printouts only. They cannot be saved.

Auto ECG report example
A: 3 rows, 4 columns. B: Patient data. C: ECG measurements. D: Automatic ECG interpretation (optional). E: Report status
label. F: Rhythm leads. G: Gain, speed, AC filter, frequency range, date and time, software version, device ID, practice ID.
H: Calibration pulse.

Rhythm ECG report example

Directions for use Introduction 3

Features

Pacemaker detection

The software detects the possible presence of a pacemaker. If you confirm that the
patient has a pacemaker, the ECG report includes no interpretation, and it indicates that a
pacemaker was detected.

Automatic ECG interpretation (optional)

The optional MEANS interpretation algorithm, developed by the University of Rotterdam
in the Netherlands, provides automatic analysis of ECG tests. For more information, see
the MEANS Physicians' Manual or the PEDMEANS Physicians’ Manual on the CD that
came with your electrocardiograph. The MEANS algorithm is used for adult patients 18
years and older. The PEDMEANS algorithm is used for pediatric patients from 1 day
through 17 years old.

4 Introduction Welch Allyn CP 50 resting electrocardiograph

Power button

Mounting holes for the
CP 50 mobile-stand
adapter (optional)

AC power indicator

Battery door

Auto ECG button

Rhythm ECG button

Printer-door latch

Ethernet connector (RJ45
for PC), functional on
CP 50 Plus only

Patient-cable connector

Mini USB connector
(for PC)

USB connector
(for mass-storage device, printer)

AC power inlet

Equipotential
terminal

AC fuses

Pressure point for closing
the printer door

Controls, indicators, and connectors

Directions for use Introduction 5

Symbols

Documentation symbols

Warning
(Warnings indicate conditions or practices
that could lead to illness, injury, or death.)

Consult operating instructions.

Operation symbols

Power on/standby Search

Auto ECG Rhythm ECG

Accept Close

Caution
(Cautions indicate conditions or practices
that could damage the equipment or
other property.)

Previous Next

Help Menu

Backspace

Power symbols

(LED off) No AC power is present. Battery is absent or faulty.

(LED green) AC power is present, and battery
is fully charged. (LED amber) AC power is
present, and battery is charging.

Alternating current Battery is charging.

Dangerous voltage Battery door

Fuse Rechargeable battery

Protective earth Nonionizing electromagnetic radiation

Battery is charged to the indicated level.

Equipotential terminal Lithium ion

6 Introduction Welch Allyn CP 50 resting electrocardiograph

-20°C

+50°C

7

min

Connectivity symbols

USB Ethernet (RJ45)

Shipping, storing, and environment symbols

This end up Keep dry.

Fragile Relative humidity limit

Temperature limits

Separate the battery from other
disposables for recycling.

Separate the device from other
disposables for recycling.
See www.welchallyn.com/weee.

Miscellaneous symbols

Heartbeats per minute Hot surface. Do not touch.

Manufacturer Date of manufacture

Defibrillation-proof Type CF applied parts Defibrillation-proof Type BF applied parts

Reorder number Serial number

Atmospheric air-pressure limits

Recycle.

China RoHS (restriction of hazardous
substances) symbols for control of pollution
caused by electronic information products.
5-year environment-friendly use period (EFUP)
for batteries. 10-year EFUP for the device.
For details, see the accompanying
documentation.

Do not reuse. Batch code

Meets essential requirements of European

European community representative

Medical Device Directive 93/42/EEC.

Software activation code

Directions for use Introduction 7

General warnings

Warnings indicate conditions or practices that could lead to illness, injury, or death.

Warnings related to the environment

WARNING To avoid a possible explosion, do not use the electrocardiograph in
the presence of flammable anesthetics: mixtures containing air, oxygen, or
nitrous oxide.

WARNING When transporting the electrocardiograph on a cart, tuck the patient
cable away from the wheels so that it does not present a hazard.

Warnings related to accessories and other equipment

WARNING For operator and patient safety, peripheral equipment and
accessories that can come in direct patient contact must be in compliance with all
appropriate safety, EMC, and regulatory requirements.

WARNING All signal input and output (I/O) connectors are intended for
connection of only devices complying with IEC 60601-1, or other IEC standards
(for example, IEC 60950), as appropriate to the device. Connecting additional
devices to the electrocardiograph might increase chassis or patient leakage
currents. To maintain operator and patient safety, consider the requirements of
IEC 60601-1-1. Measure the leakage currents to confirm that no electric shock
hazard exists. In the case of a USB printer, the printer (non-medical electrical
equipment) shall be situated outside the patient environment (reference IEC
60601-1-1). The printer used should be approved to the appropriate safety
standard for non-medical electrical equipment (IEC 60950, or its national variants),
and use of an isolation transformer is recommended. If there is a requirement for
the printer to be situated within the patient environment it is the responsibility of
the user to ensure that the system provides a level of safety in compliance with
IEC 60601-1 and 60601-1-1.

WARNING The electrocardiograph has not been designed for use with high­frequency (HF) surgical equipment and does not protect against hazards to the
patient.

8 Introduction Welch Allyn CP 50 resting electrocardiograph

Warnings related to using the electrocardiograph

WARNING This device captures and presents data reflecting a patient’s
physiological condition. When reviewed by a trained physician or clinician, this
data can be useful in determining a diagnosis. However, the data should not be
used as a sole means for determining a patient’s diagnosis or prescribing
treatment.

WARNING To avoid serious injury or death, take these precautions during
patient defibrillation:

• Avoid contact with the electrocardiograph, patient cable, and patient.

• Verify that the patient leads are properly connected.

• Place defibrillator paddles properly in relation to electrodes.

• After defibrillation, pull each patient lead out of the patient cable and inspect
the tips for charring (black carbon marks). If there is any charring, the patient
cable and individual leads must be replaced. If there is no charring, fully
reinsert the leads into the patient cable. (Charring can occur only if a lead is
not fully inserted into the patient cable before defibrillation.)

WARNING To prevent the spread of infection, take these precautions:

• Dispose of single-use components (for example, electrodes) after using them
once.

• Regularly clean all components that come in contact with patients.

• Avoid ECG testing for patients with open, infectious sores.

WARNING Avoid positioning any leads or cables so that they could easily trip
someone or become wrapped around a patient’s neck.

WARNING To ensure safe use of the device, follow the documented
maintenance procedures.

WARNING Only qualified service personnel should attempt to repair the
electrocardiograph. In case of a malfunction, call Technical Support.

WARNING Do not perform ST segment analysis on the ECG screen display,
since these ECG representations are scaled. Make manual measurements of
ECG intervals and magnitudes on printed ECG reports only.

WARNING To avoid injury, do not touch the print head immediately after printing.
It might be hot.

Directions for use Introduction 9

General cautions

Cautions indicate conditions or practices that could damage the equipment or other
property.

Caution When removing the electrocardiograph from storage, allow it to
thermally stabilize to surrounding environmental conditions before using it.

Caution To prevent possible damage, do not use sharp or hard objects to press
the touch screen or the buttons. Only use fingertips.

Caution Do not expose the patient cable to strong ultraviolet radiation.

Caution Do not pull or stretch the patient cable. Doing so could result in

mechanical or electrical failures. Form the patient cable into a loose loop before
storing.

Caution Avoid positioning the patient cable where it might get pinched,
stretched, or stepped on. Otherwise, measurements might no longer be
accurate, and repair might be necessary.

Caution Using the equipotential terminal for anything but grounding purposes
may contribute to damage of the device.

Caution Use only parts and accessories, including thermal paper, that were
supplied with the device and available through Welch Allyn. The use of
accessories other than those specified may result in degraded performance or
unsafe use of this device.

Caution Portable and mobile RF communications equipment can affect the
performance of the electrocardiograph.

Caution The electrocardiograph meets the Class A requirements of
IEC 60601-1-2 regarding incidental emission of radio frequency interference. As
such it is suitable for use in commercial grade electrical environments. If the
electrocardiograph is used in residential grade electrical environments and you
experience incidental interference with other equipment that uses radio
frequency signals to operate, minimize the interference.

Caution Other medical equipment—including but not limited to defibrillators,
ultrasound machines, pacemakers, and other stimulators—may be used
simultaneously with the electrocardiograph. However, such devices may disturb
the electrocardiograph signal.

Caution The power cord must be disconnected from AC power before
cleaning, maintaining, transporting, or servicing.

10 Introduction Welch Allyn CP 50 resting electrocardiograph

Caution The requirements of AAMI EC11, Section 3.2.7.2, Frequency and
Impulse Response, for an impulse triangle waveform may be impacted by up to
5 milliseconds of small amplitude dampened ringing immediately after the
impulse when the muscle filter (35 Hz) is turned on or a small amplitude offset
when the baseline filter (0.5 Hz) is turned on. These requirements are unaffected
by any other combination of filters turned on or off. Measurements performed by
the optional interpretation algorithm are unaffected by any filter selections.

11

2

Setup

Connecting the patient cable

WARNING Do not allow the conductive parts of the patient cable, electrodes, or
associated connections of defibrillation-proof applied parts, including the neutral
conductor of the patient cable and electrodes, to come into contact with other
conductive parts, including earth ground. Otherwise, an electrical short might
result, risking electric shock to patients and damage to the device.

WARNING To avoid injury to the patient or damage to the device, never plug
patient leads into any other device or wall outlet.

Caution Always connect the patient cable and the leads properly during
defibrillation. Otherwise, the connected leads could be damaged.

12 Setup Welch Allyn CP 50 resting electrocardiograph

3

2

4

a

b

1

ba

Loading the thermal paper

The electrocardiograph prints on z-fold thermal paper or roll thermal paper.

• Store the paper in a cool, dry, dark place.

• Do not expose it to bright light or UV sources.

• Do not expose it to solvents, adhesives, or cleaning fluids.

• Do not store it with vinyls, plastics, or shrink wraps.

To load z-fold thermal paper

Directions for use Setup 13

4

3

5

1

2

a

b

ba

To load a roll of thermal paper

14 Setup Welch Allyn CP 50 resting electrocardiograph

AC power
indicator

Battery
indicator

Powering the electrocardiograph

The electrocardiograph runs on AC or battery power. Plug the electrocardiograph into
AC power as often as possible so that the built-in charger can keep the battery charged.
Regardless of the battery condition, you can use the electrocardiograph whenever it is
plugged in.

WARNING When you use AC power, always plug the
electrocardiograph into a hospital-grade outlet to avoid the risk of
shock.

WARNING If the integrity of the building’s safety ground is in
doubt, operate this device on battery power to avoid the risk of
shock.

To power up or power down

Press .

Directions for use Setup 15

Menu
(CP 50 Plus example)

About the menu

The menu provides access to the saved patient tests, the settings, and the service
functions. From either of the main screens, you can reach the menu by touching the
menu button.

16 Setup Welch Allyn CP 50 resting electrocardiograph

Viewing or changing the settings

Three types of settings are available:

•The ECG settings, which control the content and format of your reports. In CP 50 Plus

models, these settings include a second report format (auto report 2), customizable
patient data fields, and auto save options.

•The System settings, which control the overall device.

•The Security settings, which control user login and the audit trail.

To view or change the settings

1. Touch the menu button.

2. Touch Settings > ECG or System or Security.

3. Make changes as needed.

Viewing the device information

You can view device information in two places:

•The About screen, which lists the model number, serial number, software versions,

RAM usage, available NAND.

•The Upgrade screen, which lists the installed options.

To view the device information

1. Touch the menu button.

2. Touch Settings > System > About or Upgrade.

Directions for use Setup 17

Verifying proper operation

To ensure the accuracy of test data, you should verify proper operation of the
electrocardiograph before it is used for the first time with patients. You should reverify
proper operation once a year.

To verify proper operation

1. Use an ECG simulator to acquire and print a standard 12-lead ECG of known
amplitude and rate.

2. Look for the following indications of proper operation:

• Printing should be dark and even across the page.

• There should be no evidence of print-head dot failure (no printing breaks forming

horizontal streaks).

• Thermal paper should move smoothly and consistently during printing.

• The waveforms should have no distortion or excessive noise.

• The amplitude and rate of the waveforms should match the input value from the

ECG simulator.

• Z-fold thermal paper should stop with perforations near the tear bar, indicating

proper cue-sensor operation.

3. If you see any indications of improper operation, call Welch Allyn Technical Support.

18 Setup Welch Allyn CP 50 resting electrocardiograph

Connecting to an external USB printer (optional, CP 50 Plus only)

You can connect a CP 50 Plus electrocardiograph to an external printer. The printer must
be a USB inkjet or laser printer that supports PCL (printer control language).

No special software is required.

The external printer prints auto ECG reports, always in black and white. (Rhythm ECGs
always print to the internal printer.)

Cables longer than three meters have not been verified for use with the
electrocardiograph. Do not use cables longer than three meters.

To connect to an external USB printer

1. Connect one end of a USB cable to the printer’s USB connector, and connect the
other end to the electrocardiograph’s USB connector.

2. Enable the external printer.

a. Touch the menu button.

b. Touch Settings > ECG > Auto report 1 or Auto report 2.

c. Under Printer, select External.

Directions for use Setup 19

Connecting to a CardioPerfect workstation (optional, CP 50 Plus only)

You can connect a CP 50 Plus electrocardiograph to a Welch Allyn CardioPerfect
workstation via USB cable or via Ethernet cable. After you connect, you can do the
following from the electrocardiograph:

• Send ECG tests to the workstation.

• Search for patient data in the workstation database.

Cables longer than three meters have not been verified for use with the
electrocardiograph. Do not use cables longer than three meters.

To connect to a workstation via USB cable

Connect the electrocardiograph to any of the workstation’s USB ports. No software
configuration is required. The electrocardiograph is ready to communicate.

To connect to a network-connected workstation via Ethernet cable

1. Connect the electrocardiograph to the same network as the workstation. If you need
help, consult with your network administrator.

WARNING To reduce the risk of fire and shock hazards, connect Ethernet
cables within the boundaries of a single building. Ethernet cables that span
multiple buildings can introduce fire or shock hazards unless fiber optic cables
or lightning arrestors are properly installed or other appropriate safety
measures are taken.

2. Go to the CP 50 connectivity screen.

a. Touch the menu button.

b. Touch Settings > System > Network.

3. Fill in the screen.

• If DHCP is enabled for the network, select the DHCP checkbox.

• If DHCP is not enabled, fill in the fields: static IP address, subnet mask, and

default gateway.

20 Setup Welch Allyn CP 50 resting electrocardiograph

4. Touch Te s t .

5. Connect to the network.

a. In the Host Address field, enter the host IP address.

b. Touch Ping Test. The electrocardiograph pings the host.

c. Touch Server Test. The electrocardiograph connects to the server.

The electrocardiograph is ready to communicate with the workstation. (To set up the
workstation, see the instructions that came with the workstation connectivity
software.)

21

3

TXT ID __ (Do not translate.)

ECG testing

Attaching the leads to the patient

Proper lead attachment is important for a successful ECG. The most common ECG
problems are caused by poor electrode contact and loose leads. Follow your local
procedures for attaching the leads to the patient. Here are some common guidelines.

WARNING Electrodes can cause allergic reactions. To avoid
this, follow the electrode manufacturer’s directions.

To attach the leads to the patient

1. Prepare the patient.

• Describe the procedure. Explain the importance of holding still during the test.

(Movement can create artifact.)

• Verify that the patient is comfortable, warm, and relaxed. (Shivering can create

artifact.)

• Put the patient in a reclining position with the head slightly higher than the heart

and legs (the semi-Fowler's position).

GRAPHIC ID __ (Do not translate.)

TXT ID __ (Do not translate.)

2. Select the electrode locations. (See the “Electrode locations” chart.)

• Look for flat areas.

• Avoid fatty areas, bony areas, and major muscles.

3. Prepare the electrode locations.

• Shave or clip the hair.

• Thoroughly clean the skin, and lightly rub it dry. You may use soap and water,

isopropyl alcohol, or skin preparation pads.

22 ECG testing Welch Allyn CP 50 resting electrocardiograph

4. Attach the lead wires to the electrodes.

5. Apply the electrodes to the patient.

TXT ID __ (Do not translate)

TXT ID __ (Do not translate)

Electrode examples, left to right: arm clamp (reusable), Welsh cup (reusable), tab electrode (disposable),
monitoring electrode (disposable).

• For reusable electrodes: Use electrode paste, gel, or cream to cover an area the

size of each electrode but no larger. Secure the arm and leg clamps. Apply the
Welsh cups (suction electrodes) to the chest.

• For disposable tab electrodes: Place the electrode tab between the “jaws” of

the connector. Keep the tab flat. Verify that the metal portion of the connector
makes contact with the skin side of the electrode tab.

• For all disposable electrodes: Lightly tug on the connector to ensure that the

lead is securely attached. If the electrode comes off, replace it with a new
electrode. If the connector comes off, reconnect it.

Directions for use ECG testing 23

Electrode locations

AB

J

AHA IEC Location

AV1

(red)

BV2

(yellow)

CV3

(green)

DV4

(blue)

EV5

(orange)

FV6

(purple)

GLA

(black)

HLL

(red)

IRL

(green)

JRA

(white)

C1

(red)

C2

(yellow)

C3

(green)

C4

(brown)

C5

(black)

C6

(purple)

L

(yellow)

F

(green)

N

(black)

R

(red)

C

D

E

F

G

HI

Fourth intercostal space at the right sternal border.

Fourth intercostal space at the left sternal border.

Midway between V2 and V4.

Fifth intercostal space to the left of the midclavicular
line.
Anterior axillary line at the same horizontal level as V4.

Mid-axillary line at the same horizontal level as V4 and
V5.
Just above the left wrist on the inside of the arm.

Just above the left ankle.

Just above the right ankle.

Just above the right wrist on the inside of the arm.

24 ECG testing Welch Allyn CP 50 resting electrocardiograph

Filters buttonSpeed buttonGain button

(size)

Leads button

Performing an ECG test

1. Attach the leads to the patient. Any flashing dots on the lead-status screen indicate
unattached or poorly attached leads.

When all leads have been attached for several seconds, the ECG preview screen
appears.

2. If an Artifact message appears, minimize the artifact, as described under
Troubleshooting. You might need to ensure that the patient is comfortably warm,
reprepare the patient’s skin, use fresh electrodes, or minimize patient motion.

3. (Optional) Adjust the waveforms, using the buttons to cycle through the options:

• leads displayed

• gain (size)

• speed

• filters

4. Perform the desired type of test: stat ECG, auto ECG, or rhythm ECG.

Directions for use ECG testing 25

For auto ECGs, you can enter patient data automatically if it is available.

• The search button gives you access to patient data in the test directory or in

a connected database (CardioPerfect workstation or EMR).

• The Worklist button (CP 50 Plus only) gives you access to patient data in the

worklist.

5. If a Waiting for 10 seconds of quality data message appears, at least 10 seconds of
ECG data have been collected with excessive artifact. Minimize the artifact, as
described under Troubleshooting. Then wait for the test to print. If necessary, you can
override the wait time and print the available data immediately, but the result might be
an incomplete or poor-quality test.

6. After the test prints, select the desired option: Reprint, Save, or Retest. (Any tests
that you save to a USB mass-storage device can be retrieved only from a
CardioPerfect workstation.)

WARNING To avoid the risk of associating reports with the
wrong patients, make sure that each test identifies the patient.
If any report does not identify the patient, write the patient
identification information on the report immediately following the
ECG test.

26 ECG testing Welch Allyn CP 50 resting electrocardiograph

27

4

Administrative tasks

Turning the security option on or off (CP 50 Plus only)

The electrocardiograph incorporates security features that can keep patient data
confidential. When the security option is off, user login is never required. When the
security option is on, user login is required for the following tasks:

• searching for patient data

• managing the test directory

• managing the worklist

• managing the user list

• managing the audit trail

A user’s level of access is either “user” or “administrator,” as determined in the user list.

To turn the security option on or off

1. Touch the menu button.

2. Touch Settings > Security.

3. Turn the security option on or off.

28 Administrative tasks Welch Allyn CP 50 resting electrocardiograph

Managing the user list (CP 50 Plus only)

The user list, which is enabled when the security option is on, identifies all individuals
who are authorized to access patient data.

The user list can hold up to 25 users. After the list reaches 25 users, you can add users
only if some users are set to inactive status. New users replace inactive users. If all 25
users are active, you receive a message that the user list is full.

Two levels of access can be assigned:

• User level

User-level users have access to the test directory and the worklist, including
searching and editing privileges.

• Administrator level

Administrator-level users have user-level access and can also create and administer
users.

To manage the user list

1. Touch the menu button.

2. Touch Settings > System > Users.

3. Add, edit, delete, activate, or deactivate users.

Turning the audit trail on or off (CP 50 Plus only)

An audit trail, a collection of information about user activity, may be helpful or even
required for record-keeping. It records the user identity code and time associated with
each use of the electrocardiograph, including these types of activity:

• accessing the test directory

• searching the worklist

• editing patient data

• accessing administrative functions

When the audit trail is turned on, the electrocardiograph collects this type of information
in a file in its memory.

To turn the audit trail on or off

1. Touch the menu button.

2. Touch Settings > Security.

3. Turn the audit trail on or off.

Directions for use Administrative tasks 29

Managing the worklist (CP 50 Plus only)

The worklist is a group of patients whose demographic data has been entered into the
electrocardiograph memory to be recalled for a test later that day. The worklist holds up to
50 patients.

When you perform an auto ECG, you can fill in the patient’s data from the worklist
automatically by touching the Worklist button.

You can add or delete patients any time. If the electrocardiograph is connected to an
EMR, you can also download a worklist.

To ma n ag e t h e w o r kl i st

1. Touch the menu button.

2. Touch Worklist.

3. Add patients, delete patients, or download a worklist.

Managing the test directory

The test directory is a group of ECG tests that have been saved in the electrocardiograph
memory. The test directory holds at least 25 ECG tests.

When you perform an auto ECG, you can fill in the patient’s data from the test directory
automatically by touching the search button.

With all electrocardiograph models, you can delete or print saved tests.
With CP 50 Plus models, you can also do the following:

• Edit the patient data in saved tests.

• Send saved tests to a USB mass-storage device or to a Welch Allyn CardioPerfect
workstation. (Any tests that you send to a USB mass-storage device can be retrieved
only from a CardioPerfect workstation.)

To manage the test directory

1. Touch the menu button.

2. Touch Tests.

3. Delete, edit, print, or send saved tests. (Options vary per model.)

30 Administrative tasks Welch Allyn CP 50 resting electrocardiograph

31

2

3

4

1

Disconnect the power plug from the AC outlet.

Turn off the electrocardiograph. (Press and hold the power button for
at least six seconds until the screen goes blank.)

Dampen a cloth with any of the acceptable cleaning solutions, and
wipe the exterior of the patient cable and electrocardiograph. Dry all
components with a clean, soft cloth, or paper towel.

Before you turn on the electrocardiograph again, wait at least
10 minutes for all traces of liquid to evaporate.

5

Maintenance

Cleaning the equipment

WARNING Keep the electrocardiograph and the patient cable clean.
Patient contact with contaminated equipment can spread infection.

Caution Never let soap or water come into contact with the
electrocardiograph’s internal printer, connectors, or jacks.

Caution Never immerse the electrocardiograph or the patient cable in liquid.
Never autoclave or steam clean the electrocardiograph or the patient cable.
Never pour alcohol directly on the electrocardiograph or the patient cable, and
never soak any components in alcohol. If any liquid enters the
electrocardiograph, remove the electrocardiograph from service, and have it
inspected by a qualified service person before using it again.

Acceptable cleaning solutions:

• Mild detergent and water, ½ tsp detergent per cup of water

• Bleach and water, 1 part bleach (6.00% sodium hypochlorite) with 9 parts water

• Isopropyl alcohol and water, 70% by volume

• PDI® Sani-Cloth® Plus wipes (14.85% isopropanol)

• CaviWipes™ (17.2% isopropanol)

To clean the equipment (monthly or more often if needed)

32 Maintenance Welch Allyn CP 50 resting electrocardiograph

Inspecting the equipment

Perform the following inspections daily.

• Check for cracked or broken patient cable, patient electrodes, power cord,
communications cables, display, and enclosure.

• Check for bent or missing pins on all cables.

• Check all cable and cord connections; reseat if any connectors are loose.

Testing the electrocardiograph

Welch Allyn recommends verifying proper operation of the electrocardiograph once a year
to ensure reliability. See “Verifying proper operation” on page 17.

Whenever the electrocardiograph is serviced or whenever problems are suspected,
verify continued electrical safety of the device using IEC 60601-1 or ANSI/AAMI ES1
methods and limits.

WARNING Only qualified service personnel should perform leakage
current tests.

Test for the following:

• Patient leakage current

• Chassis leakage current

• Earth leakage current

• Dielectric strength (AC and patient circuits)

Directions for use Maintenance 33

2

3

4

5

6

1

8

7

Replacing the battery

Replace the battery under these circumstances:

• It loses its charge quickly.

• You have charged it, and the electrocardiograph still does not turn on when
unplugged.

The first time that you press the power button after installing a new battery, the
electrocardiograph goes through some diagnostic tests that cause it to take longer than
usual to power up.

Discard the old battery appropriately. Contact your local authorities concerning recycling.

To replace the battery

34 Maintenance Welch Allyn CP 50 resting electrocardiograph

If either fuse is dark or has a broken wire,
replace the fuse. Line up the fuse case with
the opening; it goes in only one way.

2

4

1

3

5

Replacing the AC fuses

You might need to replace one or both of the AC fuses if the AC power indicator does not
light up when the electrocardiograph is connected to AC power.

WARNING Failure to unplug could result in electrocution.

To replace the AC fuses

Storing the equipment

When storing the electrocardiograph, cords, and accessories, observe the environmental
storage conditions that are identified in the product specifications.

Discarding the equipment

Discard the electrocardiograph, cords, and accessories according to local laws.

Do not dispose of this product as unsorted municipal waste. Prepare this
product for reuse or separate collection as specified by Directive 2002/96/EC of
the European parliament and the Council of the European Union on Waste
Electronic and Electrical Equipment (WEEE). If this product is contaminated,
this directive does not apply. For more specific disposal information, see
www.welchallyn.com/weee, or contact Welch Allyn Customer Service at
[phone].

35

6

Troubleshooting

Lead-quality problems

“Artifact” message on the screen

Artifact is signal distortion that makes it difficult to accurately discern the waveform
morphology.

Causes

• The patient was moving.

• The patient was shivering.

• There is electrical interference.

Actions

See actions for wandering baseline, muscle tremor, and AC interference.

Wandering baseline

Wandering baseline is an upward and downward fluctuation of the waveforms.

Muscle tremor

Causes

• Electrodes are dirty, corroded, loose, or positioned on bony areas.

• The electrode gel is insufficient or dried.

• The patient has oily skin or used body lotions.

• Rising and falling of chest during rapid or apprehensive breathing.

Actions

• Clean the patient’s skin with alcohol or acetone.

• Reposition or replace the electrodes.

• Verify that the patient is comfortable, warm, and relaxed.

• If wandering baseline persists, turn the baseline filter on.

Muscle tremor interference superimposes random, irregular spikes on the waveforms.

36 Troubleshooting Welch Allyn CP 50 resting electrocardiograph

Causes

• The patient is uncomfortable, tense, nervous.

• The patient is cold and shivering.

• The exam bed is too narrow or short to comfortably support arms and legs.

• The arm or leg electrode straps are too tight.

Actions

• Verify that the patient is comfortable, warm, and relaxed.

• Check all electrode contacts.

• If interference persists, turn the muscle-tremor filter on. If interference still persists,
the problem is probably electrical in nature. See the suggestions for reducing AC
interference (in a related troubleshooting tip).

AC interference

AC interference superimposes even-peaked, regular voltage on the waveforms.

Causes

• The patient or technician was touching an electrode during recording.

• The patient was touching a metal part of an exam table or bed.

• A lead wire, patient cable, or power cord are broken.

• Electrical devices in the immediate area, or lighting, or wiring concealed in walls or
floors are interfering.

• An electrical outlet is improperly grounded.

• The AC filter is turned off or set incorrectly.

Actions

• Verify that the patient is not touching any metal.

• Verify that the AC power cable is not touching the patient cable.

• Verify that the proper AC filter is selected.

• If interference persists, unplug the electrocardiograph from AC power and run it on
the battery. If this solves the problem, you’ll know that the noise was introduced
through the power line.

• If interference still persists, the noise may be caused by other equipment in the room
or by poorly grounded power lines. Try moving to another room.

Lead alert or square wave

A dot might be flashing on the lead-status screen. Or one or more leads might appear as a
square wave.

Causes

• Electrode contact might be poor.

• A lead might be loose.

• A lead might be defective.

Directions for use Troubleshooting 37

Actions

• Replace the electrode.

• Verify that the patient’s skin has been properly prepared.

• Verify that electrodes have been properly stored and handled.

• Replace the patient cable.

System problems

The electrocardiograph won't turn on when it is plugged in.

Causes

• The AC power connection is faulty.

• An AC fuse is blown.

• There is no AC power.

Actions

• Check the AC power source.

• Check the AC fuses.

The electrocardiograph won't turn on when it is unplugged.

Causes

• The battery is disconnected or incorrectly connected.

• The battery is low, not charging, depleted, or bad.

Actions

• Check the battery connections.

• Recharge the battery.

• Replace the battery.

The electrocardiograph shuts down during printing.

Causes

• The battery is low or bad.

Actions

• Recharge the battery.

• Replace the battery.

The electrocardiograph prints fewer than 10 reports on a full battery charge.

Causes

• The battery is degraded.

Actions

• Replace the battery.

The electrocardiograph does not respond when you press buttons or touch the screen.

Causes

• The electrocardiograph is frozen.

38 Troubleshooting Welch Allyn CP 50 resting electrocardiograph

Actions

• Reset the electrocardiograph by pressing and holding the power button for at least six
seconds until the screen goes blank. Press the power button again. The
electrocardiograph goes through some diagnostic tests that cause it to take longer
than usual to power up.

For more troubleshooting guidelines, see the service manual.

Caution The service manual is for use only by qualified service personnel who

understand technical English.

Directions for use Troubleshooting 39

Limited warranty

Welch Allyn, Inc., warrants that the CP 50 and CP 50 Plus electrocardiographs (the
Products) meet the labeled specifications of the Products and will be free from defects in
materials and workmanship that occur within 1 year after the date of purchase, except
that accessories used with the Products are warranted for 90 days after the date of
purchase. Such accessories include cables, electrodes, and battery.

The date of purchase is: 1) the date specified in our records, if you purchased the Product
directly from us, 2) the date specified in the warranty registration card that we ask you to
send to us, or 3) if you don’t return the warranty registration card, 30 days after the date
on which the Product was sold to the dealer from whom you bought the Product, as
documented in our records.

This warranty does not cover damage caused by: 1) handling during shipping, 2) use or
maintenance contrary to labeled instructions, 3) alteration or repair by anyone not
authorized by Welch Allyn, and 4) accidents.

If a product or accessory covered by this warranty is determined to be defective because
of defective materials, components, or workmanship, and the warranty claim is made
within the warranty period described above, Welch Allyn will, at its discretion, repair or
replace the defective Product or accessory free of charge. If your Product requires repairs
covered by this warranty, upon your request Welch Allyn will loan to you, at no cost, a
substitute Product for use until your repaired Product is returned.

You must obtain a return authorization from Welch Allyn to return your Product before you
send it to Welch Allyn’s designated service center for repair. Contact Welch Allyn
Technical Support.

THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILTY
AND FITNESS FOR A PARTICULAR PURPOSE. WELCH ALLYN’S OBLIGATION UNDER
THIS WARRANTY IS LIMITED TO REPAIR OR REPLACEMENT OF PRODUCTS
CONTAINING A DEFECT. WELCH ALLYN IS NOT RESPONSIBLE FOR ANY INDIRECT OR
CONSEQUENTIAL DAMAGES RESULTING FROM A PRODUCT DEFECT COVERED BY
THE WARRANTY.

40 Troubleshooting Welch Allyn CP 50 resting electrocardiograph

Service policy

All repairs on products under warranty must be performed by Welch Allyn or by a service
provider authorized by Welch Allyn. Unauthorized repairs will void the warranty. In
addition, whether or not covered under warranty, any product repair should be performed
exclusively by Welch Allyn or by a service provider that has been authorized by Welch
Allyn.

If the product fails to function properly—or if you need assistance, service, or spare
parts—contact the nearest Welch Allyn Technical Support Center.

Before contacting Welch Allyn, try to duplicate the problem, and check all accessories to
ensure that they are not causing the problem. When calling, please be prepared to
provide:

• Product name, model number, and serial number of your product.

• Complete description of the problem.

• Complete name, address and phone number of your facility.

• For out-of-warranty repairs or spare parts orders, a purchase order (or credit card)

number.

• For parts orders, the required spare or replacement part numbers.

If your product requires warranty, extended warranty, or non-warranty repair service,
please call first the nearest Welch Allyn Technical Support Center. A representative will
assist you troubleshooting the problem and will make every effort to solve it over the
phone, avoiding potential unnecessary return of your product.

In case a return cannot be avoided, the representative will record all necessary
information and will provide a Return Material Authorization (RMA) number, as well as the
appropriate return address. An RMA number must be obtained prior to any return.

If you have to return your product for service, follow these recommended packing
instructions:

• Remove all hoses, cables, sensors, power cords, and other accessories (as

appropriate) before packing, unless you suspect they are associated with the
problem.

• Wherever possible use the original shipping carton and packing materials.

• Include a packing list and the Welch Allyn Return Material Authorization (RMA)

number.

It is recommended that all returned goods be insured. Claims for loss or damage to the
product must be initiated by the sender.

41

A

Specifications

Item Specification

Dimensions, including rubber feet
(length x height x width)

Weight 2.0 kg (4.4 lb)

Keyboard type (power, auto ECG,
and rhythm ECG buttons)

Display

Typ e
Resolution

Thermal paper

Z-fold
Roll

Thermal printer (internal) Computer-controlled dot array, 8 dots/mm

Thermal-chart-paper speeds 10, 25, 50 mm/s

Gain settings

Auto ECGs
Rhythm ECGs

Lead configurations Standard, Cabrera

32.5 x 8 x 18.8 cm (12.8 x 3.1 x 7.4 in.)

Polyester overlay

TFT, 11 cm (4.3 in.) color touch screen
WQVGA, 480 x 272

11.4 cm (4.5 in.) x 250 sheets

11.4 cm (4.5 in.) x 20 m

2.5, 5, 10, 20 mm/mV, AUTO

2.5, 5, 10, 20 mm/mV

Report formats, internal printer*

Auto ECGs
Rhythm ECGs
Average cycles

Report formats, external printer*

Auto ECGs
Average cycles

ECG storage (in test directory) At least 25 ECG tests

Patient storage (in worklist,
CP 50 Plus only)

Frequency range 0.3 to 150 Hz

Digital sampling rate > 1,000 samples/second/channel

Pacemaker detection ANSI/AAMI EC11

Power requirement Universal AC power supply 110-240 V~, 50/60 Hz ~, 1.5 A maximum

AC fuses Time-lag type, 2.0-amp 250-V rating, Littlefuse 0218002P or equivalent

Rechargeable battery 10.8V, 1.9Ah minimum, 3-cells Li-ion “smart” battery. A fully charged battery prints

3x4, 3x4+ 1R, 2x6
3 leads
3x4 + 3R @ 25 mm/s, 3x4 + 3R @ 50 mm/s, 2x6 + 1R @ 25 mm/s,

2x6+1R@50mm/s

3x4, 3x4+ 1R, 3x4 + 3R, 6x2,12x1
3x4 + 3R @ 25 mm/s, 3x4 + 3R @ 50 mm/s, 2x6 + 1R @ 25 mm/s,

2x6 + 1R @ 50 mm/s, 3x4 + 2R @ 25 mm/s, 3x4 + 2R @ 50 mm/s,
6x2+2R@50 mm/s

Up to 50 patients

up to 25 ECGs with one extra copy per test.

42 Specifications Welch Allyn CP 50 resting electrocardiograph

Item (Continued) Specification (Continued)

Filters

High-performance baseline
Muscle tremor
AC interference

0.5 Hz
35 Hz
50 Hz or 60 Hz

Safety, EMC, and regulatory
compliance

ANSI/AAMI EC11** UL60601-1
CAN/CSA C22.2 No. 601.1 IEC/EN 60601-1
CAN/CSA C22.2 No. 601.1.1 IEC/EN 60601-1-1
CAN/CSA C22.2 No. 601.1.2 IEC/EN 60601-1-2
CAN/CSA C22.2 No. 601.1.4 IEC/EN 60601-1-4
CAN/CSA C22.2 No. 601.2.25 IEC/EN 60601-1-6

IEC/EN 60601-2-25
IEC/EN 60601-2-51 (2x6 lead arrangement)

Standard connectivity Mini USB client and USB host, Ethernet (CP 50 Plus only)

Connectivity with electronic

Through the Welch Allyn CardioPerfect workstation software

medical records (CP 50 Plus only)

Electrodes Rigorously tested for conductivity, adhesion, and hypoallergenic qualities, and

exceed all AAMI standards

Power cable Meets or exceeds Type SJT.

Patient cable and leads Meets or exceeds ANSI/AAMI EC53, EN/IEC 60601-2-25 and EN/IEC 60601-2-51.

Environmental operating conditions

Temperature
Relative humidity
Atmospheric air-pressure limits

+10° C to +40° C (+50° F to +104° F)
15 - 95% noncondensing (30 - 70% for printing)
700 - 1060 hPa

Environmental storage conditions

Temperature
Relative humidity
Atmospheric air-pressure limits

-20° C to +50° C (-4° F to +122° F)
15 - 95% noncondensing
700 - 1060 hPa

Protection against electric shock Class I, internally powered

Typ e B F

Mode of operation Continuous

* If you print at a high gain setting, the waveform or calibration marks might be clipped. This clipping does not comply

with clause 51.103.1 of the IEC/EN 60601-2-51 standard. Use a lower gain setting to observe the full waveform.

** Per AAMI EC11:1991/(R)2001 Diagnostic Electrocardiographic Devices, Section 3.1.2.1 Disclosure of cautionary information/

performance characteristics paragraph c) Accuracy of input signal reproduction, the manufacturer shall disclose the methods used to
establish overall system error and frequency response. Welch Allyn has used methods A & D, as prescribed in section 3.2.7.2 and

4.2.7.2 of this same standard, to verify overall system error and frequency response. Because of the sampling characteristics and the
asynchronism between sample rate and signal rate, digital ECG systems such as the CP 50 may produce a noticeable modulating effect
from one cycle to the next, particularly in pediatric recordings. This phenomenon is not physiologic.

Specifications are subject to change without notice.

EMC guidance and manufacturer’s

43

B

declarations

Electromagnetic emissions

The CP 50 electrocardiograph is intended for use in the electromagnetic environment specified below. The customer or
user of the CP 50 electrocardiograph should assure that it is used in such an environment.

Emissions test Compliance Electromagnetic environment - guidance

RF emissions

CISPR 11

RF emissions

CISPR 11

Harmonic emissions

IEC 61000-3-2

Voltage fluctuations/
flicker emissions

IEC 61000-3-3

Group 1 The CP 50 electrocardiograph uses RF energy only for its internal

Class A The CP 50 electrocardiograph is suitable for use in all establishments

Class A

Complies

function. Therefore, its RF emissions are very low and are not likely to
cause any interference in nearby electronic equipment.

other than domestic and those directly connected to the public low­voltage power supply network that supplies buildings used for domestic
purposes.

44 EMC guidance and manufacturer’s declarations Welch Allyn CP 50 resting electrocardiograph

Electromagnetic immunity

The CP 50 electrocardiograph is intended for use in the electromagnetic environment specified below. The customer or
user of the CP 50 electrocardiograph should assure that it is used in such an environment.

Immunity test IEC 60601

test level

Electrostatic discharge
(ESD)

IEC 61000-4-2

Electrical fast transient/
burst

IEC 61000-4-4

Surge

IEC 61000-4-5

Voltage dips, short
interruptions, and
voltage variations on
power supply input
lines.

IEC 61000-4-11

Power frequency
(50/60Hz)
magnetic field

IEC 61000-4-8

± 6 kV contact

± 8 kV air

±2 kV for power supply
lines

±1 kV for input/output
lines

±1 kV differential mode

±2 kV common mode

>95% dip in 0.5 cycle

60% dip in 5 cycles

30% dip for 25 cycles

>95% dip in 5 seconds

3 A/m 3 A/m Power frequency magnetic fields should

Compliance level Electromagnetic environment -

guidance

± 6 kV contact

± 8 kV air

±2 kV for power supply
lines

Not applicable

±1 kV differential mode

±2 kV common mode

>95% dip in 0.5 cycle

60% dip in 5 cycles

30% dip for 25 cycles

>95% dip in 5 seconds

Floors should be wood, concrete, or
ceramic tile. If floors are covered with
synthetic material, the relative humidity
should be at least 30%.

Mains power quality should be that of a
typical commercial or hospital
environment.

Mains power quality should be that of a
typical commercial or hospital
environment.

Mains power quality should be that of a
typical commercial or hospital
environment. If the user of the CP 50
electrocardiograph requires continued
operation during power mains
interruptions, it is recommended that
the CP 50 electrocardiograph be
powered from an uninterruptible power
supply or battery.

be at levels characteristic of a typical
location in a typical commercial or
hospital environment.

Directions for use EMC guidance and manufacturer’s declarations 45

P

P

P

Electromagnetic immunity

The CP 50 electrocardiograph is intended for use in the electromagnetic environment specified below. The customer or
user of the CP 50 electrocardiograph should assure that it is used in such an environment.

Immunity test IEC 60601

test level

Conducted RF
IEC 61000-4-6

Radiated RF
IEC 61000-4-3

3 Vrms
150 kHz to 80 MHz

3 V/m
80 MHz to 2.5 GHz

Compliance

Electromagnetic environment - guidance

level

Portable and mobile RF communications equipment
should be used no closer to any part of the CP 50
electrocardiograph, including cables, than the
recommended separation distance calculated from
the equation applicable to the frequency of the
transmitter.

Recommended separation distance

3 Vrms d = (1.17)

3 V/m d = (1.17) 80 MHz to 800 MHz

d = (2.33) 800 MHz to 2.5 GHz

where P is the maximum output power rating of the
transmitter in watts (W) according to the transmitter
manufacturer and d is the recommended separation
distance in metres (m).

Field strengths from fixed RF transmitters, as
determined by an electromagnetic site survey,
should be less than the compliance level in each
frequency range.

b

a

Interference may occur in the vicinity of equipment
marked with the following symbol:

Note 1: At 80 MHz and 800 MHz, the higher frequency range applies.
Note 2: These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption and reflection from

structures, objects, and people.

a

Field strengths from fixed transmitters, such as base stations for radio (cellular/cordless) telephones and land mobile radios, amateur

radio, AM and FM radio broadcast and TV broadcast cannot be predicted theoretically with accuracy. To assess the electromagnetic
environment due to fixed RF transmitters, an electromagnetic site survey should be considered. If the measured field strength in the
location in which the CP 50 electrocardiograph is used exceeds the applicable RF compliance level above, the electrocardiograph
should be observed to verify normal operation. If abnormal performance is observed, additional measures may be necessary, such
as reorienting or relocating the electrocardiograph.

b

Over the frequency range 150 kHz to 80 MHz, field strengths should be less than 3 V/m.

46 EMC guidance and manufacturer’s declarations Welch Allyn CP 50 resting electrocardiograph

PPP

Recommended separation distances between portable
and mobile RF communications equipment and the CP 50
electrocardiograph

The CP 50 electrocardiograph is intended for use in an electromagnetic environment in which radiated RF disturbances
are controlled. The customer or user of the CP 50 electrocardiograph can help prevent electromagnetic interference by
maintaining a minimum distance between portable and mobile RF communications equipment (transmitters) and the
CP 50 electrocardiograph as recommended below, according to the maximum output power of the communications
equipment.

Separation distance according to frequency of transmitter (m)

Rated max. output

power of transmitter

(W)

0.01 0.117 0.117 0.233

0.1 0.37 0.37 0.74

1 1.17 1.17 2.33

10 3.70 3.70 7.37

100 11.70 11.70 23.30

For transmitters rated at a maximum output power not listed above, the recommended separation distance d in meters (m) can be

estimated using the equation applicable to the frequency of the transmitter, where P is the maximum output power rating of the

transmitter in watts (W) according to the transmitter manufacturer.
Note 1: At 80 MHz and 800 MHz, the separation distance for the higher frequency range applies.
Note 2: These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption and reflection from

structures, objects, and people.

150 kHz to 80 MHz

d = (1.17)

80 MHz to 800 MHz

d = (1.17)

800 MHz to 2.5 GHz

d = (2.33)