Amrex MS324C Series User manual

*Federal law (USA) restricts this device to sale by or on the order of a licensed practitioner licensed by the law of the state in which
he practices to use or order the use of this device.
User's Guide
MS324C*
Low Volt AC Stimulator
Amrex
®
electrotherapy equipment
a division of Amrex-Zetron, Inc.

AMREX®electrotherapy equipment
a division of Amrex-Zetron, Inc.
7034 Jackson Street
Paramount, California 90723
[phone]
Toll Free Customer Service [phone]
Fax [phone]
E-Mail: [e-mail]
Web Site: http://www.amrexusa.com
MS324C User's Guide
Low Volt AC Stimulator
Revised February 2014
Copyright © Amrex-Zetron, Inc. 1995. All rights reserved.
Printed in the United States of America
The following are registered or trademarked by Amrex:
Amrex®
SynchroSonic®
Flextrode®

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Thank you. . .
for selecting the Amrex MS324C Low Volt AC Stimulator. We believe that you will
find this instrument to be versatile, dependable and user friendly. The MS324C is
designed for the application of low volt ac muscle stimulation. The Amrex MS324C
Low Volt AC Stimulator is a dual-channel, four-pad, low voltage electrical muscle
stimulator that produces pulsation, tetanize, surge and reciprocal output. The
electrical muscle stimulation may be applied separately or may be combined with
ultrasound simultaneously through the ultrasound transducer using an external
Amrex SynchroSonic®U/50.
Your MS324C has been manufactured by a group of dedicated, highly trained
employees who exemplify the sixty-year Amrex tradition of manufacturing
therapeutic equipment of the highest quality while supporting you with prompt,
courteous customer service.
Upon receipt of your MS324C, verify your accessories against the enclosed check
list. Promptly return the postage paid Registration Card to Amrex. Save the original
shipping carton and all packing materials.
Please carefully review this User’s Guide prior to operating the Amrex MS324C
Low Volt AC Stimulator. Should you have questions regarding your new purchase,
or need assistance, telephone Amrex Technical Services at [phone].

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Limited Warranty
Amrex-Zetron, Inc. (Manufacturer) warrants each instrument it manufactures to be free from
defects in material and workmanship under normal use and service for a period of two (2) years
from the date of purchase. This two-year warranty extends only to the original purchaser and shall
not apply to batteries, fuses, accessories or any instrument which has been subjected to misuse,
neglect, accident or abnormal conditions of operation.
The Manufacturer's obligation under this warranty is limited to repairing or replacing, at the
Manufacturer's option, any instrument returned to the factory within two (2) years from the date
of purchase. If the Manufacturer determines that the product fails to conform to this warranty
due to misuse, alteration or abnormal condition of operation, including evidence that nonauthor-
ized personnel have attempted to repair the device, the instrument will be repaired at customer's
expense. This warranty is exclusive and in lieu of all other warranties, expressed or implied,
including but not limited to any other warranty of merchantability or fitness for any particular
purpose. Manufacturer shall not be liable for any special, incidental or consequential damages,
whether in contract, tort or otherwise.
Service and Shipping Information
Amrex Technical Services has a representative to assist you should your equipment require service
or repair. It is necessary to obtain a Return Merchandise Authorization (RMA) number before return-
ing equipment to the factory for warranty repair. Call our representative toll free [phone].
Damage, resulting from repairs made outside the factory, is not covered under the warranty.
To maintain original design specifications, your Amrex muscle stimulator must be calibrated
and safety tested on an annual basis. Amrex strongly recommends that servicing be referred to
the factory. Call toll free [phone].
Save the original shipping carton and all packing materials to safely return Amrex equipment
to the factory for service, repair, annual calibration, electrical and mechanical safety check. All
accessories, including the ac line cord, must be included with the returned instrument. The
customer is responsible for all freight charges. The Manufacturer shall assume NO responsibility
for damage in transit.

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Contraindications—Warnings—Precautions
THIS INSTRUMENT OPERATES ON 150/230 VOLTS AC, 50/60 Hz. (unless otherwise indicated on
the unit) AND MUST BE PROPERLY GROUNDED FOR SAFETY. The three wire power cord with
"hospital grade" plug should be connected to a GROUNDED AC wall receptacle. It is the personal
responsibility and obligation of the user to insure that this instrument is properly connected to the
AC POWER source before use.
Warning–Risk of burns and fire. DO NOT use near conductive
material such as metal bed parts or innerspring mattresses. Renew
electrode cables upon evidence of deterioration. Use of controls,
adjustment, or performance of procedures, other than those specified
herein, may result in hazardous exposure to electrical energy.
Important
AMREX Intensity Reset Circuit: The Amrex Low Volt AC Stimulator incorporates a unique
safety reset function as part of the intensity controls. This is to prevent any sudden or inadvertent
stimulation output to the patient in the event that:
• The Low Volt AC Intensity controls are not set to the 0/Reset position enabling the
audible/ tactile "clicks" at power on.
• The ac power is interrupted during treatment.
• The treatment period has ended.
• The Patient Treatment Stop Switch is activated.
The Low Volt AC Intensity controls must be returned to the 0/Reset position enabling the audible/
tactile "clicks", a treatment time selected, and the Start Timer control pressed before stimulation
output can be activated.
When the Amrex Low Volt AC Stimulator safety reset function is initiated, stimulator output will
be discontinued immediately, the Reset Intensities indicator light will flash and an audible signal
will be emitted from the generator. The Intensity controls must be returned to the 0/Reset position,
enabling the audible/tactile "clicks", a treatment time selected, and the Start Timer control pressed
before stimulator output can be activated.
Note: The generator will default to factory settings unless the treatment period has ended
without interruption or the Patient Treatment Stop Switch has been activated.
Patient "Treatment Stop" Switch: When the patient "Treatment Stop" switch is activated, stimulator
output will be discontinued immediately. The Reset Intensities indicator light will flash and an
audible signal will be emitted from the generator. Stimulator output cannot be resumed until the
Low Volt AC Intensity controls for Channel A and Channel B are returned to the 0/Reset position
enabling the audible/tactile "clicks" which will turn off the Reset Intensities indicator light, a
treatment time selected, and the Start Timer control pressed. NOW the stimulator output can be
activated.
Note: All generator settings are maintained except the treatment time which reverts to the
factory default setting of fifteen minutes.

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Electrical Muscle Stimulation—Contraindications
• Contraindicated for patients with cardiac demand pacemakers.
• Should not be used on cancer patients.
Electrical Muscle Stimulation—Warnings
• Long term effects of chronic electrical stimulation are unknown.
• Safety has not been established for the use of electrical muscle stimulation during
pregnancy.
• Adequate precautions should be taken in the case of persons with suspected heart
problems.
• Adequate precautions should be taken in the case of persons with suspected or diagnosed
epilepsy.
• Do not stimulate over the carotid sinus nerves, especially in patients with a known sensitivity
to the carotid sinus reflex.
• Severe spasm of the laryngeal and pharyngeal muscles may occur when the electrodes are
positioned over the neck or mouth. The contractions may be strong enough to close the
airway or cause difficulty in breathing.
• Electrical muscle stimulators should not be applied transcerebrally.
• Electrical muscle stimulators should not be used over swollen, infected or inflamed areas
or skin eruptions.
• Caution should be used in the transthoracic application of electrical muscle stimulators in
that the introduction of electrical current into the heart may cause arrhythmias.
• Electrical muscle stimulators should be kept out of the reach of children.
Electrical Muscle Stimulation—Precautions
Precautions should be observed:
• When there is a tendency to hemorrhage following acute trauma or fracture.
• Following recent surgical procedures when muscle contraction may disrupt the healing
process.
• Over the menstruating uterus.
• Where sensory nerve damage is present by a loss of normal skin sensation.
Some patients may experience skin irritation or hypersensitivity due to the electrical
stimulation or the conductive medium. The irritation can usually be reduced by use of an
alternate conductive medium or alternate electrode placement.
Skin irritation and burns beneath the electrodes have been reported with the use of electrical
muscle stimulators.

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Table of Contents
Part 1
Overview..................................................................................................................................1
Part 2
Power/Timer Section...............................................................................................................5
Part 3
Low Volt AC Stimulator Modality ......................................................................................9
Part 4
MS324C General Operation and Application Procedures..............................................19
General Operation .......................................................................................................................19
Application of Electrical Muscle Stimulation ..........................................................................23
Adverse Effects - Shortwave Diathermy Interference ............................................................24
Electrical Muscle Stimulation—Indications ............................................................................25
Electrical Muscle Stimulation—Contraindications ................................................................25
Electrical Muscle Stimulation—Warnings................................................................................25
Electrical Muscle Stimulation—Precautions............................................................................26
Appendix A
Specifications ........................................................................................................................27
Appendix B
References...............................................................................................................................29

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