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Q: Class A, Class B Certification ( Answered,   0 Comments )
Subject: Class A, Class B Certification
Category: Miscellaneous
Asked by: sfinancial-ga
List Price: $100.00
Posted: 27 May 2005 05:03 PDT
Expires: 26 Jun 2005 05:03 PDT
Question ID: 526221
Can someone explain to me the difference between class a and class b
certification in regards to payment processors, terminals, etc, etc.
Subject: Re: Class A, Class B Certification
Answered By: jackburton-ga on 27 May 2005 15:52 PDT
All electronics products sold in the United States are required by the
Federal Communications Commission (FCC) to obtain an FCC mark showing
that the product complies with the following standards:
- Emissions (the effect on other electronic devices of energy radiated
from the product)
- Immunity (the product's response to other electronic devices) 
There are two categories that your product can fall into: Class A or Class B.
A Class A device is a product marketed for commercial or industrial
use and is not intended to to be used in a home.
A Class B device is a product marketed for residential or home use.
Class B requirements tend to be stricter than Class A requirements.
"The FCC Rules and Regulations, Title 47, Part 15, Subpart B regulates
"unintentional radio-frequency devices". Products regulated include
any unintentional radiator (device or system) that generates and uses
timing pulses at a rate in excess of 9000 pulses (cycles) per second
and uses digital techniques. This includes almost every product that
employs a microprocessor including workstations, personal computers,
point-of-sale terminals, printers, modems, and many electronic games.
It is illegal to sell or advertise for sale any products regulated
under Part 15, Subpart B until their radiated and conducted emissions
have been measured and found to be in compliance.
Most products regulated by Part 15, Subpart B fall into one of two
categories. Class A devices are those that are marketed for use in a
commercial, industrial or business environment. Class B devices are
those that are marketed for use in the home. Class B limits are more
stringent than Class A limits and the Class B certification process is
administratively more rigorous than the Class A verification process.
The radiated and conducted EMI test procedures are defined in the ANSI
Standard C63.4. FCC Rules and Regulations, Part 15, only regulates
radio frequency emissions. Currently there are no FCC regulations
pertaining to product immunity to electromagnetic fields."
UMR EMC LAB: EMC Regulations 
From the 'Product Safety Engineering' website:
"What does the FCC mean by Class A or Class B?
Class A
A device which is marketed for use in an industrial application and is
not intended for use in the home or residential area. Since the
product is being sold to a commercial market, the emissions limits are
significantly less stringent than Class B (residential) devices.
Products that fall under the category of Class A do not require an
official submittal, but simply need a Verification test performed and
the data must be keep on hand by the manufacturer.
Class B
A device that is marketed for use in the home or a residential area by
the customer. Class B devices can require either Verification,
Certification, or Self Declaration depending on the type of product.
Class B Verification is for devices that are marketed for in home use,
but are not permanently connected to a personal computer. Computing
devices and peripherals need to meet the same test limits, but the
formal data needs to be submitted to the FCC for Certification, or the
manufacturer can choose to issue a Declaration of Conformity under the
new FCC DoC/Self Declaration Procedures."
This site gives a good overview of electromagnetic compatibility (EMC)
requirements of information technology equipment (ITE) like payment
"The FCC?s Rules are contained in Title 47 of the U. S. Code of
Federal Regulations, which contains 99 Parts. Part 15 contains the
requirements for devices that do not require a license for their
operation. These include equipment that uses radio frequencies
deliberately for communication or information transfer, such as
cordless telephones or wireless LAN transmitters, and ?incidental
radiators,? for which the escape of RF energy by radiation or
induction is accidental and not a necessary or intended part of the
equipment?s operation. ITE clearly falls within this category.
The FCC imposes limits on the signals that can be conducted down the
lines powering the equipment in the frequency range of 0.15 to 30 MHz.
These line conducted emissions limits have been aligned with those of
CISPR 22, which are in common use around the world.
The FCC also limits radiated emissions above 30 MHz from ITE. The
upper range of concern varies with the highest internal frequency used
within the equipment (see Table 1). This upper range of interest
differs from the requirements in countries that base their
requirements on CISPR 22, which requires measurement to 1 GHz
(extension of that range is under discussion).
The FCC divides equipment into two main classes by the type of
location they are marketed for. ?Class A? equipment is that used in
commercial or light industrial settings; ?Class B? equipment is that
used by consumers in residential settings. Different limits apply,
with the Class A limits approximately 10 dB (roughly a factor of 3)
more lenient. The rationale for this difference is based on the
anticipated mean distance separating potential interferences sources
and victims (i.e., receivers of interference), which is expected to be
larger in a non-residential setting.
In addition to the major classifications based on location--?A? or
?B?--the FCC also pays special attention as to whether or not a Class
B device is a personal computer or personal computer peripheral. This
attention is reflected in the method of approval. There are three
possible methods of equipment approval for devices regulated under
Part 15:
* Verification 
* Certification 
* Declaration of Conformity 
Table 2 shows which approval method should be used for different types
of equipment. For completeness, we have shown the approval routes for
all Part 15-regulated equipment, (...)
Verification is the approval method for Class A digital devices, Class
B external switching supplies, and Class B digital devices which are
not PC-related, as shown in the last four entries of the table. The
?verification? procedure is as defined by the FCC matches the common
definition of that word. (FCC 2.951 ff.) That is, the manufacturer of
?verified? equipment is required to test the equipment to verify that
it meets the FCC?s technical requirements, and to ensure that the
equipment will continue to meet the FCC?s requirements by being
?identical to the unit tested.... within the variation that can be
expected due to quantity production...?
Links concerning emission limits:
Test Services - Information Technology Testing
FCC Rules - Part 15.109 Radiated emission limits
FCC Rules - Part 15 - Radio Frequency Devices
New Guidelines - FCC Part 15 Mandate
Professional Testing - Emissions
I hope this information is useful.
If anything is unclear, please request clarification.
Best regards,
Google Answers Researcher
Search terms used:
certification "class a" "class b" fcc, "federal communications commission"
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