Adjustable Power Resistor 7.5 Ohm 50W
Power adjustable (variable, regulated) resistor 7.5 Ohm 50 Watt – wirewound load chassis mount resistors of type APT series (Adjustable Painted Tubular Resistors). Resistor 7R5 50W – rated resistance is 7.5 Ohm, power dissipation is 50W.
Resistors with a specific rated power can also be manufactured to individual order. Other similar series of resistors are RX20, RXG, ASE, AST, AVE, AVT, D50K, L50J.
Resistors are designed for using in AC and DC circuits, providing current limitation and voltage distribution. The maximum operating voltage at AC is 1000V, at DC – 1400V. Operating elevated ambient temperature does not exceed +155°C (at the same time the power is reduced to 60% of the nominal power), the limit temperature up to +250°C. The insulation resistance of wire resistors is at least 1000 MOhm. Working time – at least 15000 hours.
Structurally, the resistor consists of a tubular ceramic core on which a constantan (low resistance resistor) or nichrome (high resistance resistor) wire is wound. Resistors are coated with heat-resistant and moisture-resistant insulating paint.
Resistor resistance is adjusted by changing the position of the moving clamping collar (movable contact) along the case (tube). The contact between the clamping collar and the wire coils of the resistor is provided by the unpainted side of the housing.
Contacts, resistor leads are rigid, tape type with screw holes or for soldering conductors. Kind of mounting is hinged. Mounting of resistors on the panel is provided by a set of fasteners. Resistance tolerance is ±5%, ±10%.
Using the calculator, it is convenient to calculate the total resistance when the resistors are connected in parallel or in series, and the resistor resistance in the circuit.
Comparative characteristics of wire tube resistors, cement resistors and resistors in aluminium housing are presented in the comparative table.
Detailed resistor specifications, overall and mounting dimensions, mounting kit, installation and operation recommendations are given on the page below.
Our company is engaged in the production and sale of wirewound tubular resistors. All our products pass strict quality control and meet the necessary standards. Since we are the manufacturer, and in the price of the final product does not include dealer markups, we have low price saddle packing.
The warranty period of the resistors 50W supplied by our company is 2 years. Documents confirming the quality of products are provided.
The final price for 7.5 Ohm 50W Adjustable Variable Power Resistors depends on the quantity, delivery terms and form of payment.
For questions regarding the acquisition of Adjustable Power Resistors 50W, send an email request to:
And we will provide you a commercial offer for delivery.
For a large number, we will provide an individual price!!!
We are open to manufacture products at our production facilities
according to your requests and technical task.
Electrical and technical specifications of Adjustable Power Resistors 50 Watt:
|Power rating||50 Watt|
|Series of nominal resistance values||E24, Datasheet of resistance values|
|Resistance tolerance||± 5%, ± 10%|
|Rated voltage||Vmax = (Pnom × Rnom)0.5|
|Maximum working voltage||1400V|
|Operating temperature||-60°C ... +155°C|
|Raised ambient operating temperature||70ºC|
|Relative humidity at 35°C without condensation||<98%|
|Temperature coefficient of resistance||±500 ppm/°C|
|Insultation resistance||1000 MOhm|
|Life time||15000 hours|
|Dimensions D×L×H×d||30×90×43×20 mm|
Part Numbering Guide for Adjustable Resistor 50W 7.5 Ohm:
|APT||–||Adjustable Painted Tubular Resistor Series.|
|50W||–||Rated Power, Watts.|
|7.5 Ohm||–||Nominal Resistance, Ohm.|
Mounting Hardware for Power Wirewound Tubular Resistors 50 Watt
Mounting hardware are used for mounting the resistors. Resistors can be supplied with a set of mounting hardware, including mounting brackets (corners), which must be ordered individually.
Completeness of Mounting Hardware for Power Wirewound Tubular Resistors
|Item||Power: 25W, 50W, 75W, 100W, 160W|
|Threaded rod M5||1 pcs.|
|Ceramic bushing||2 pcs.|
|Screw-nut M5||2 pcs.|
|Flat washer||2 pcs.|
|Spring washer||2 pcs.|
|Asbestos washer||2 pcs.|
|Brackets (Corners)||2 pcs.|
Installation methods of tube resistors
At influence of mechanical factors for resistors the hinged way of installation is applied. The resistors are fixed to the mounting plates by mounting hardware:
- resistor power from 3 to 25 Watt – cantilever or on two brackets at the ends of the mounting studs
- resistor power from 50 to 160 Watt – only on two brackets at the ends of the mounting studs
Overall and Mounting Dimensions of Adjustable Power Wirewound Tubular Resistors 50 Watt:
|L, mm||L1, mm||ØD, mm||H, mm||Ød, mm||Ød1, mm||B, mm||A, mm|
Power Wirewound Tubular Ceramic Resistors by AS ENERGI
Our company is engaged in the manufacturer and sale of power wirewound tubular resistors fixed and adjustable types.
You can buy resistors from us in any volumes, and when ordering large lots, the price will be lower.
We have earned the trust of customers and supply products all over the world.
To purchase Power Resistors, send an email request to:
And we will provide you a commercial offer for delivery.
Datasheet (pdf specification) for Adjustable Variable Power Resistors:
Guide for using and operation of resistors:
- Solder the wires to the resistor leads in specially designed holes.
- When installing resistors in equipment recommended to use Sn40Pb60 solder. Soldering iron core temperature is 300°C. Soldering iron power is 65W. The flux should consist of 25% by weight of rosin and 75% by weight of isopropyl or ethyl alcohol. Soldering time 5 s.
- The voltage that can be supplied to the resistor must not exceed the value calculated on the basis of the nominal (or allowable) power Pnom and nominal resistance Rnom according to the formula:
Vmax = (Pnom × Rnom)0.5
- Resonant frequency value - 1500 Hz.
- 95-percent work resource - 30 000 hours.
- It is allowed to operate resistors under the influence of gas media of this composition (without the formation of an explosive mixture):
- nitrogen – up to 96%;
- oxygen – up to 50%;
- carbon dioxide – up to 3%;
- hydrogen – up to 20%;
- helium – up to 1%;
- argon – up to 1,5%.
- Operation of resistors during and after exposure to atmospheric pressure reduced to 10~5 mm Hg is allowed.
- In electrical circuits with voltages above 500V resistors must be used with additional insulation at the mounting points.
- When using resistors in equipment with vibration loads from 1 to 2500 Hz with an acceleration of 176.6 m/s2 (18g), the resistor leads must be soldered with a 0.5 mm2 wire cross-section with insulation by a polychlorovinyl tube Ø4 mm and length of 15-20 mm – for resistors 5-25 W, and Ø5 mm and length of 15-20 mm – for resistors 50-100 W.
- Tensile force value should be 20N (2 kgf).
- The upper frequency of the range in which there should be no resonant frequencies – 1000 Hz.
- Maximum surface temperature of the resistor is not more than 250°C.
Graph of the resistor power reduction:
The load power should be reduced based on the derating curve once the ambient temperature exceeds the rated values.
Comparative performance of high power resistors: