AC, AC-AT
www.vishay.com Vishay Draloric
Revision: 11-Jul-2018 4Document Number: 28730
For technical questions, contact: ww1resistors@vishay.com
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
DESCRIPTION
Wirewound resistors are best suited for use in high power,
high current applications. The silicon cement lacquer
coating enables AC series to withstand challenging
operating and environmental conditions. The coating is
resistant to cleaning solvents specified in IEC 60115-1 (1).
Production is strictly controlled and follows an extensive set
of instructions established for reproducibility.
The winding is done with a specific material on a specially
developed fine ceramic body (Al2O3). The ceramic meets the
highest requirements against mechanical resistance,
thermal shocks, dielectric strength, and insulation
resistance at high temperatures. With different diameters
and turn spacings of resistive wire, a large ohmic value
range can be covered.
The resistors are marked with resistance, rated dissipation
(P40) and tolerance. Product quality is verified by testing
procedures, performed on all individual resistors.
Resistance is measured on the lead wires at a distance of
6 mm from the resistor body. If a greater length of lead wire
is used in the application, the user may need to consider the
additional wire resistance, particularly with low resistance
products.
MATERIALS
Vishay acknowledges the following systems for the
regulation of hazardous substances:
• IEC 62474, Material Declaration for Products of and for the
Electrotechnical Industry, with the list of declarable
substances given therein (2)
• The Global Automotive Declarable Substance List
(GADSL) (3)
• The REACH regulation (1907/2006/EC) and the related list
of substances with very high concern (SVHC) (4) for its
supply chain
The products do not contain any of the banned substances
as per IEC 62474, GADSL, or the SVHC list, see
www.vishay.com/how/leadfree. Hence the products fully
comply with the following directives:
• 2000/53/EC End-of-Life Vehicle Directive (ELV) and
Annex II (ELV II)
• 2011/65/EU Restriction of the Use of Hazardous
Substances Directive (RoHS) with amendment
2015/863/EU
• 2012/19/EU Waste Electrical and Electronic Equipment
Directive (WEEE)
Vishay pursues the elimination of conflict minerals from
its supply chain, see the Conflict Minerals Policy at
www.vishay.com/doc?49037.
ASSEMBLY
The resistors are axial leaded for soldering. The terminals of
the resistors are completely lead (Pb)-free, the special tin
plating provides compatibility with lead (Pb)-free and
lead-containing soldering processes.
Special lead forms may be available on request, please
inquire at ww1resistors@vishay.com. These components
are high dissipation power resistors, customers are advised
to use a high melting point solder.
APPLICATION INFORMATION
The power dissipation of the resistor generates a
temperature rise with respect to the ambient. The
permissible dissipation is derated for temperatures above
40 °C, as shown in the derating diagram, in order to avoid
overheating of the resistor. The heat dissipated from the
resistor may affect adjacent components, hence proper
clearance will be required in order to avoid overheating. The
resistive wire is encapsulated by a protective lacquer
coating.
All materials used are non-flammable and inorganic.
These resistors do not feature a limited lifetime when
operated within the permissible limits. However, resistance
value drift increasing over operating time may result in
exceeding a limit acceptable to the specific application,
thereby establishing a functional lifetime.
APPROVALS
The AC-AT series is AEC-Q200 qualified, specifically for use
in automotive applications.
RELATED PRODUCTS
UL approved, special cement coated fusible resistor is also
available. For details please see the datasheet:
“AC01-CS, AC03-CS, AC05-CS - Axial Cemented Fusible
Wirewound Safety Resistors” www.vishay.com/doc?28909
For high surge wirewound products, silicon cement coated
Z300-Cxx series is available, see the datasheet:
“Z300-Cxx - High Surge Axial Cemented Wirewound
Resistors” www.vishay.com/doc?21027
For precision applications, cement coated PAC series is
available, see the datasheet:
“PAC Series - Cemented Wirewound Precision Resistors”
www.vishay.com/doc?28731
Notes
(1) Other cleaning solvents with aggressive chemicals should be evaluated in actual cleaning process for their suitability
(2) The IEC 62474 list of declarable substances is maintained in a dedicated database, which is available at http://std.iec.ch/iec62474
(3) The Global Automotive Declarable Substance List (GADSL) is maintained by the American Chemistry Council and available at www.gadsl.org
(4) The SVHC list is maintained by the European Chemical Agency (ECHA) and available at http://echa.europa.eu/candidate-list-table