Wirewound Resistors
23Pages

Wirewound Resistors Hardware Reference Document 1101072 - Edition June 2009

Wirewound Resistors Hardware Reference Email: commercial@coudoint.com Website: www.coudoint.com Address: 19 Avenue de la gare Document 1101022 – Edition June 2009 Information and products subject to change without prior notice

Wirewound Resistors Hardware Reference 1 Main Features Series and models: We offer standard models in the RCA series and special models in other series. Resistor assemblies can be supplied as open frames, available to OEM's for mounting in their own enclosure, or in indoor/outdoor enclosures according to a specified IP level. RCA Series: The RCA Series consists of 12 models in different sizes, with wattages from 7 to 1325 watts, and ohmic values from 0.1 Ω to 440 kΩ, with different types of coating, terminal connections, mounting bracket (see Product Selection Guide on page 4). Description...

Wirewound Resistors Hardware Reference 2 RCA Series 2.1 Product Selection Guide This matrix shows, for each RCA model, the dimensions of the ceramic core, the power rating P M and the range of ohmic values RT which can be supplied, depending on the resistor type (fixed, adjustable, corrugated tape wound) and its coating : A selection by the maximum current IM can be done with PM and RT, IM being defined by PM = RT x I²M. It is important to consider that the current must not exceed the maximum allowed value at every point of the resistance wire and that precautions may have to be taken...

Wirewound Resistors Hardware Reference 2.2 Features by Type of Coating and of Wire or Tape 2.2.1 Cement Coated RCA Resistors Main features • • • • wide range of ohmic values mechanically robust good overload capacity excellent resistance to thermal shock Features by model Power rating is given: • for continuous duty [for intermittent duty: please contact us ] • for adjustable resistors: for the position of the adjustable terminal that provides an ohmic value close to the maximum Minimum ohmic value (Ω) Maximum ohmic value (kΩ) Minimum ohmic value (Ω) Maximum ohmic value (kΩ) Fixed resistors...

Wirewound Resistors Hardware Reference 2.2.2 Silicone Coated RCA Resistors Main features • • wide range of ohmic values mechanically robust Features by model Power rating is given: • for continuous duty [for intermittent duty: please contact us ] • for adjustable resistors: for the position of the adjustable terminal that provides an ohmic value close to the maximum Minimum ohmic value (Ω) Maximum ohmic value (kΩ) Minimum ohmic value (Ω) Maximum ohmic value (kΩ) Fixed resistors : Adjustable resistors : Document 1101022 – Edition June 2009 Information and products subject to change without...

Wirewound Resistors Hardware Reference 2.2.3 Vitreous Enamelled RCA Resistors Main features • • • vitreous enamel coated winding excellent protection of the winding, capable of withstanding harsh environmental conditions not available for RCA-11 and RCA-12 models Features by model Power rating is given: • for continuous duty [for intermittent duty: please contact us ] • for adjustable resistors: for the position of the adjustable terminal that provides an ohmic value close to the maximum Minimum ohmic value (Ω) Maximum ohmic value (kΩ) Minimum ohmic value (Ω) Maximum ohmic value (kΩ) Fixed...

Wirewound Resistors Hardware Reference 2.2.4 Corrugated Tape Wound RCA Resistors Main features • • • • • only available for RCA-6 to RCA-10 vitreous enamel coating low ohmic values high currents very good heat dissipation • low inductance Corrugated tape wound resistors are not supplied with adjustable lugs and are not available, with an “Ayrton-Perry” type winding option. Electrical specification Power rating is given for continuous duty [for intermittent duty: please contact us ] Minimum ohmic value (Ω) Maximum ohmic value (Ω)

Wirewound Resistors Hardware Reference 2.3 Temperature Rise Curves 2.3.1 Round wirewound models: for continuous duty (intermittent duty: please contact us), temperature rise above ambient (25°C) versus dissipated power is shown below : ΔT (°C) Document 1101022 – Edition June 2009 Information and products subject to change without prior noti

Wirewound Resistors Hardware Reference The power rating depends on the ambient temperature. The percentage of variation versus ambient temperature is shown by the following derating curve: 2.3.2 Corrugated tape wound models: for continuous duty (intermittent duty: please contact us), temperature rise above ambient (25°C) versus dissipated power is shown below: Document 1101022 – Edition June 2009 Information and products subject to change without prior notice

Wirewound Resistors Hardware Reference 2.4 Mechanical Specifications 2.4.1 Overview table Mounting style Type PS Outside L-brackets Screw lugs Inside L-brackets Faston terminals Fixed resistor Intermediary taps Adjustable resistor Insulated terminals Adjustable lug – screw driver type Large adjustable lug – screw driver type Mounting clips Direct wires Uninsulated terminals Type TD Double screw driver type Large double screw driver type Ferrule terminals Document 1101022 – Edition June 2009 Information and products subject to change without prior notice

Wirewound Resistors Hardware Reference 2.4.2 Mounting Styles and Dimensions RCA resistors can be supplied unmounted, or with insulated or uninsulated terminals. The mounting brackets are white zinc-plated steel brackets. Unmounted resistor: The RCA-1 to RCA-12 models come with ceramic cores in different sizes with a circular cross-section for the RCA-1 to RCA-10 models and a nearly square cross-section for the RCA-11 and RCA-12 models. RCA-1 to RCA-10 :

Wirewound Resistors Hardware Reference Resistors with insulated mounting brackets • PS brackets PS brackets are outside L-brackets, depending on the model : - spring-grip type slotted brackets for RCA-1 to RCA-8 models : brackets fit inside the core of the resistor and remains in place with spring tension - end-slotted, through-bolt type mounting brackets for RCA-9 to RCA-12 models Document 1101022 – Edition June 2009 Information and products subject to change without prior notice