DIN rail adapter for MATE-N-LOK cap housings allows wire
and harness installers to bring two ends of a cable assembly
or wire harness together at a DIN rail mounted location.
The DIN rail adapters, from Tyco
Electronics Corporation (Harrisburg,
PA, U.S.), allow designers to enjoy the benefits of using
a proven pin and socket connector and the convenience
of DIN rail mounting.
appliance industry is increasingly designing globally. For instance,
Whirlpool Corporation (Benton Harbor, MI, U.S.) recently developed
a low-cost washing machine in Brazil for use there as well
as in China and India.
Not surprisingly, appliances
designed and produced
across borders are likely to share components. This may be
especially true with appliance companies that have preferred
support them around the world. With global markets and manufacturing,
it is hardly surprising that component standardization is
a hot topic.
the area of wire harnesses, cables, and connectors, some of the recent
momentum is coming from Europe.
RAST connectors, standardized in Europe in the 1980s, are beginning to
make their presence felt elsewhere, such as in the U.S. Europe also seems
to be taking the lead in lead; that is, many European companies are removing
lead stabilizer from wire insulation.
recent initiative, meanwhile, comes from the U.S. January 2002 saw the
release of wire harness standards under the auspices of the Wiring Harness
Manufacturer's Association (WHMA) in Eden Prairie, MN, U.S. The standard
followed several years of involvement by technical personnel from harness
makers, suppliers, and users. Among the 18 areas covered by the standard
are inspection, strand damage, solder terminations, preparing for soldering,
solder requirements, cleanliness, insulation, connection requirements,
and crimp terminations.
"Until recently, there was no group that addressed the needs of wire harness makers," reports
Larry Oden, senior engineer at Unicable Inc. (Bowling
Green, KY, U.S.). "The WHMA standards try to be comprehensive as far
as the theory of harness assembly methods without getting into the
details of the materials or the specifics of how to design for every
environment. This is still under the purview of the manufacturer, and
the standards will not inhibit innovation.
"We've been incorporating elements of the standards at critical points in our operation, and [are] using them to judge the quality of our own work," he continues. "To
date, the standards are not widely known, and most of the OEM drawings
we've gotten have not made reference to them. But we feel the standards
are valuable as a way of assuring and judging harnesses workmanship."
push-in wire connectors safely terminate any combination
of 12-18 AWG solid or tin-bonded copper conductors without
twisting to eliminate repetitive motion fatigue and provide
increased productivity. An installer glides the wire
in place using a minimal amount of insertion force. Clear
polycarbonate housings permit visual connector verification.
The connectors, from Ideal
Industries (Sycamore, IL, U.S.), come in seven multi-port
models, ranging from two to eight ports, each color-coded.
Mitch Samuels, president of Electri-Cord Manufacturing (Westfield,
PA, U.S.), also finds the WHMA standard useful. "WHMA Standard 620 has proven to be a great tool in accurately producing new products," Mr. Samuel notes. "Because
there is a fairly low barrier of entry into wire harness production, the WHMA
standard helps maintain standards and consistency on each aspect of production
from proper crimping through the soldering of joints. Appliance producers would
be prudent to check that their suppliers are producing all wire harnesses to
the strict specifications set by 620."
Out of Europe
About 15 years
ago, the European appliance industry put together a committee to standardize
connectors and harnesses for the appliance industry. "This was modeled after an approach implemented by the Japanese auto industry," recalls
John Risch, sales and marketing manager, Electronic Products for Lumberg, Inc. (Midlothian,
VA, U.S.). "Standards were established for 2.5-mm connectors used for lower current and control systems, and 5-mm connectors used for power. Today, suppliers are providing motors, switches, and other components with built-in RAST headers. Components such as turbidity sensors, which may be available only from European suppliers, have found their way to North American appliance producers. These companies need to use RAST connectors to plug into the headers," Mr.
"With RAST, appliance companies can use an IDC or crimp/snap," points
out Ronald Weber, new business development manager at Tyco Electronics Corporation (Harrisburg,
PA U.S.). "The IDC version is typically more automated, with the cable
being made and checked automatically. The equipment may even be able
to terminate and test anywhere along a wire. RAST connectors have productivity,
and sometimes ergonomic, advantages as well."
Jim Connors, account
and industry manager at Tyco, notes: "The global appliance companies
all have or are considering going to RAST, sometimes out of necessity
of the available components. While maximum RAST advantages come from
IDC, this is a big change and requires new equipment. Because of this,
North American appliance companies are considering both IDC and crimp
Mr. Risch of Lumberg
believes that all the major U.S. appliance companies are now looking
connectors. "In a global appliance industry, it makes sense to have standardized components that will be widely accepted," he explains. "Beyond
that, RAST lends itself to automation and improved reliability, and
can incorporate automated test stations."
maker BSH Bosch und Siemens Hausgeräte GmbH uses RAST connectors worldwide, including at its recently expanded major appliance production operation in New Bern, NC, U.S. "To automate the production of cable harnesses, insulation displacement is necessary," says Dr. Clemens Schaller, executive vice president of Manufacturing and Engineering. "Other
advantages are that these harnesses are easy to check so that the quality
increases and the costs go down. The insulation displacement is realized
by using RAST technology. An additional advantage affects the assembly
of the appliances. Due to the opportunity to integrate keys in the
connectors, we can reduce assembly failures."
"Modularization and standardization are the key words today," observes
Faraz Hasan, national appliance industry manager, JST Corporation (Jamestown,
NC, U.S.). "Instead of using single connections, now appliance OEMs are using more ganged-up connections, thus leading to modularization. This reduces assembly time and also chances of mis-wiring when you are assembling the wiring harness in an appliance," he
Mr. Hasan believes
that most of the appliance producers are moving toward using standard
connectors. "RAST (both crimp and IDC) is a step in this direction," he notes. "Just
like what D-Subs and USB did for the computer industry in the last
decade, RAST will do for the appliance industry in the coming years.
RAST 5 and 2.5 connectors are standardized on the pitch and most other
dimensions. Using them, you can standardize connections in an appliance.
It does not matter which connector manufacturer you use, since connectors
are the same dimensionally in most cases.
According to JST
IL, U.S.), the RSF RAST 5 PS Series provides easy and fast positive
locking to 0.250- x 0.032-in
tabs found on numerous devices such as controls, switches,
and printed circuit boards. At the heart of the system is
the low insertion force PS contact. In addition to the RSF
housings, the contact will work with all existing 0.250 PS
"What IDC RAST connectors bring to the table is speed and automation in harness manufacturing," Mr. Hasan continues. "One can achieve up to 15 parts per million (ppm) or less harness defects using fully automatic machines and IDC RAST connectors. These kinds of ppm levels are unheard of using 'crimp and poke' technology, which is inherently less automated and has a fairly high manual content," Mr.
U.S. appliance industry is primarily using this "crimp and poke" technology, according to Mr. Hasan. "Where the appliance industry would want to be in 3 to 5 years is completely into IDC RAST 5 and 2.5 technology," he says. "In
the interim, there would be a stage where one would see a mixture of
both crimp and IDC technology. Also in this interim, we will see a
considerable use of the crimp RAST 5 technology."
"In general, RAST is of interest in North America due to the increase in quality and efficiency it offers," observes
Dean Norton, marketing manager at Wago Corporation (Germantown,
WI, U.S.). "However, both of these benefits can be realized in non-RAST standard connectors. In fact, there are other connector systems available that offer greater product quality, reduced size, greater efficiencies, and broader vendor selection," he
One option appliance
producers may want to explore are the connector systems used for industrial
applications, according to Mr. Norton. "These are the connectors they themselves rely on in the manufacturing of their appliances. These connectors are highly reliable and offer greater flexibility than RAST connectors," he
Mr. Norton adds
that with much of today's manufacturing moving to low-labor-rate countries,
producers are realizing that screw and/or crimp style connectors require
a certain degree of skilled labor to properly terminate the wires. "With spring pressure connection technology, highly reliable wiring is accomplished easily - simply insert the screwdriver, insert the stripped wire, and remove the screwdriver," he explains. "The
contact pressure is pre-programmed via the spring so there is no need
for torque screwdrivers or precise crimping tools. In addition, spring
pressure connectors are vibration-proof. With this feature, you don't
have to worry about the effects of a loose screw due to the vibration
of an appliance, such as a washing machine, or due to shipping/handling
the appliance to its final destination. Another advantage of this spring
technology is that there are a number of vendors to choose from."
Materials, to a large degree, have been standardized. A material such as a wire insulator or plastic connector housing that is acceptable in one country is likely acceptable elsewhere. However, this does not mean there are no changes. Several U.S. appliance companies are now requiring connector housings to withstand a glow wire flammability test, observes Michael O'Connell, director, Product Marketing, Molex Incorporated (Lisle,
IL, U.S.). "Each manufacturer has its own procedures and requirements. We have been able to provide housing materials that can pass these tests," he
Adds Mr. Hasan
of JST, "We
are seeing most of the appliance producers mandating that materials
used to manufacture plastic parts (PA66) have a flammability rating
of UL94V0 as compared to UL94V2 that was used earlier. The UL94V0 rating
provides better self-extinguishing properties in the unlikely event
that the connector catches on fire. This causes the appliance to be
more safe in the unlikely event of a fire."
In metals, Mr.
Hasan has seen newer types of steel with better tensile and yield strength. "In fact, we are one of the first companies that is now launching a positive locking terminal in steel, which will be able to withstand temperatures up to 210°C," he explains. "This
is ideal for ranges and other high-temperature applications."
Mr. Weber of Tyco
points out: "Lead-free has not had much impact in the U.S., but it
is a way of life in Europe. For us, as we design for the global market,
figures heavily into our developments across the board. For instance,
we are going to lead-free plating baths, and using new processing techniques
for soldering lead-free terminals. This even affects the polymer housings,
since the lead-free solder baths are higher temperature, and the housings
need to withstand this."
Among some of the industry's new products are no-lead-based heat stabilizer formulations from Teknor Apex Vinyl Division that
are used in two new vinyl insulation compounds designed to provide a high level
of electrical performance in wet-location appliance and industrial wiring. "Of the applications for which the new Apex 80853C and 80853F compounds are appropriate, motor control wire presents the worst case scenario in that its vinyl insulation is thinnest," says Donald G. Ouellette, industry manager, Teknor Apex Vinyl Division (Pawtucket, RI, U.S.). "This
makes high levels of insulation resista'ce and dielectric strength of critical
importance for good performance in wet locations.
"The electrical properties of our new compounds are equivalent to those of Apex 853, a lead-stabilized compound that has long proven its reliability in the same applications," Mr. Ouellette continues. "A
wide range of our wire and cable products are now free of lead stabilizer,
yet provide electrical properties as good as or better than the compounds
they have replaced."
photo of a Bosch washing machine features RAST connectors
The connectors, which lend themselves to automation,
are widely used in Europe and are starting
to be adopted in other areas.
Mr. O'Connell of
Molex has seen an increased interest in standardized terminals in
the last 2
years. "Many companies are concentrating on using these, even if they are put into a custom housing," he says. "They
are looking to get a cost advantage by using standard, off-the-shelf
products. Besides this, when developing new models, some appliance
companies are continuing to use the same connectors from their earlier
Mr. Samuels of
Electri-Cord Manufacturing foresees OEMs cutting lead time by 66 percent
planning bare bones inventory levels by implementing the use of cross-platform
wire harnesses. "Our customers have found real value in our global manufacturing capabilities," he says. "They
have us build the large volume, steady running part numbers and universal
subassemblies in Asia and ship them to our closest North American facility,
where we warehouse them. As the rapidly changing forecasts come in,
we customize the generic subassemblies as well as build the simpler
parts in our plants in the U.S. and Mexico. This way they get the low
cost of Asian labor and materials blended in with the flexibility and
quick service of a North American supplier."
helped one of its clients, a large manufacturer of office equipment,
production efficiency. "The production manager made it clear that one of his main goals is to always keep a tight line on cost while maximizing the value and quality for his products," Mr. Samuels explains. "By
expanding the number of products in which he uses a given wire harness,
his company has benefited from both an increased economy of scale and
an even higher quality standard.
"By working cooperatively with our engineering department, he is expecting to reduce the number of different wire harnesses required by seven percent in the next 6 months," he continues. "We
are gradually integrating the use of the multi-purpose wire harnesses.
Within 12 months we should have reduced the number of different harnesses
needed by 25 percent. This change is allowing the manufacturer to benefit
by more predictable inventory levels and a significantly lower unit
cost due to the higher production volume of specific harnesses."
and Wire Harnesses
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