variable resistorsA C-shaped ceramic is wound with copper or chromium-alloy wire as a resistance element. Except for the slide contact surface, the entire component is coated with a high-temperature, non-flammable resin. After cooling and drying, insulation is applied through a high-temperature process. Then, a centered rotating adjuster component is installed, which slides along the resistance element and varies the resistance to the desired value. The scope of the application includes educational modeling, load simulations, industrial machinery RPM adjustment, voltage and current adjustment, instruments, and automated control installations. For custom specifications, please contact us to discuss the details.

FVR Type 25W - 100W
Power Wirewound Starter Resistors Power Variable Slide Resistors Power Wirewound Housed Aluminum Resistors
Dimensions(mm) Max.
A B C D E F G H I J K Weight
25W 2.5 3.2 22 3/8" 6x12 42 50 50 11 5 10 74/g 5Ω-2.5KΩ
50W 4.2 4.2 28 3/8" 6x12 64 60 70 11 8 14 160/g 7Ω-3.5KΩ
100W 4.2 4.2 42 3/8" 6x12 85 75 90 11 8 14 372/g 10Ω-5KΩ

Determination of End resistance value of FVR, DQS, DSRA, DSRB, BSR, BSQ:
Resistance Range means you can choose one maximum resistance value (End resistance value) at one of FVR, DQS, DSRA, DSRB, BSR, BSQ VR (Variable Resistor) type.
After End Resistance Value confirmed, the minimum resistance (start resistance value) will be determined by depending on resistance of wire and wirewound type.

Power Rating of Variable Resistor:
The part Nunber formation of FVR, DQS, DSRA, DSRB, BSR, BSQ:

Product type - Rated Wattage - Resistance Value (Ω) - Resistance Tolerance

Product type means one of FVR, DQS, DSRA, DSRB, BSR, BSQ.
Rated Wattage means power rating at End Resistance Value.
Resistance Value (Ω) means maximum resistance value (End resistance value).
Resistance Tolerance means precision range of End Resistance Value.

1. Power Rating of VR (Variable Resistor) is determined by the maximum resistance value (End resistance value).
2. Resistance and Power Rating should be decreased while you are adjusting the screw.

If you need currunt constant type or special specifications, please feel free to cntact us.

Performance Specifications
Test Item Test Methods Characteristics
Resistance tolerance JIS-C-5261 5-1 Resistance tolerance ±10%
Insulation resistance JIS-C-5261 6-1 500VDC 100MΩ min
Dielectric withstanding voltage JIS-C-5261 7-1 1000VDC 1 minute Between terminal and axis Free of appearance or structural irregularity
Terminal strength JIS-C-5261 6-5
3kg 30 seconds
Free of appearance or structural irregularity
ΔR/R≤ ±(2%+0.1Ω)
Vibration JIS-C-5261 6-6 1.5m/m 10 ~ 50 ~ 10 Hz/min X-Y-Z 2 hours each Free of appearance or structural irregularity
ΔR/R≤ ±(2%+0.1Ω)
Load life JIS-C-5261 7-7 Free of appearance or structural irregularity
ΔR/R≤ ±(5%+0.1Ω)
Full gyration angle JIS-C-5261 6-1 300± 5°C
Flame retardation 100% - 600% rated wattage load US UL-94 flame retardation test V-0 grade noncombustible
Remarks 1. Resistance and resistance tolerance were tested in-house with micro resistance meter.
2. Coating refers to UL-certified data provided by supplier.

How to Order
FVR 25W 2.5KR K
Part Number
Rated Wattage
Max. Resistance Value
Indicates resistance
value in units of ohms.
Resistance Tolerance
K ±10%

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