RAF 900

RAF 900

Wire coiled inserted in ceramic tube and filled with quarzite sand, sealed by dielectric cement

The RAF is a resistance made with metal case with coiled wire inserted in perforated ceramic and filled with quartzite sand. The metal case is sealed with dielectric cement and appropriate plates and is mounted on a finned dissipater; this ensures a minimum IP54 degree of protection. The RAFT model is identical to the RAF model with the addition of the thermal pad.

Overview Table

Min Resistance
Max Resistance
Tolerance (%)
Rated Continuos Power (W)
Protection Degree (IP)
Not Inductive
Maximum operating voltage permanent (V)
Thermal switch

These options are available for this product:*

ohmic values out of range,special tolerance on resistance (2%, 1%),different cable lenght *Options must be ordered separately. Contact Fairfild directly.

In what sectors is this resistance used?

The main areas of application are industrial automation and the energy sector.

For what types of applications is it used?

The product is used: in RC circuits as resistance of charging and discharging capacitor, as the dynamic braking resistor.

What are the electrical specifications?

The RAF family has 3 models with power ratings from 325 W to 415 W and the ohmic value ranges between 8.2 Ω and 360 Ω. The nominal voltage of use is 1500 V.

What are the overload conditions?

The resistance can be overloaded with respect to its nominal power based on the working cycle (insertion and rest time). For duration pulse less than one second, the overload permissible also depends on the ohmic value. For pulses of longer duration, the internal quartzite plays a decisive role in dissipating energy. See the section on overloads in the data sheet.

What is the temperature of the resistance?

The temperature of the resistance depends on the power that it will dissipate. Numerous factors influence the dissipation capacity; please consult our technical data sheet for detailed information. The graph on page 3 of the data sheet shows the relationship between the temperature on the casing and the power applied for a heating element placed horizontally.
The resistance can be installed horizontally or vertically, in this case it is necessary that the cables are facing downwards. For mounting, use the available channels on the dissipater. The provided cables that have not been stripped are used for electrical connection. The dissipater provided is not anodized.


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