RQR15/40 Series High-Power Ceramic Encased Resistors
Wire wound resistive elements encased in a fired ceramic cement housing
Model variants: RQR15 (15W/30W), RQR20 (20W) and RQR40 (40W) — including single and three-resistor network configurations
Resistance range: 0.01Ω to 54kΩ depending on model and variant
Tolerance options: ±0.5%, ±1%, ±2%, ±5% and ±10%
TCR: ±260ppm/°C maximum
Operating temperature range: −55°C to +155°C
Dielectric withstanding voltage: AC 1500V for 1 minute (max. leakage current 2mA)
Insulation resistance: 20MΩ minimum
Available in lead type (L) and screw/terminal type configurations
RQR15C and RQR40C variants offer three resistors in a single enclosure for network applications
RoHS compliant; suitable for PCB mounting and panel installation
What are the RQR15/40 Series High-Power Ceramic Encased Resistors?
The RQR15/40 series extends the RQR ceramic encased wire wound resistor family into the high-power range, covering rated power levels of 15W, 20W and 40W within the same proven ceramic cement enclosure technology used across the broader RQR range. Like all cement resistors in the RARA portfolio, the construction begins with a Wire wound resistive element — precision resistance wire wound onto a ceramic core — whose assembly is then placed into a ceramic boat, filled with high-temperature fire-retardant cement and fired to produce a rigid, non-flammable, sealed enclosure. This construction gives the series its characteristic resistance to heat, moisture and mechanical stress, making it suitable for deployment in industrial environments where standard silicone-coated resistors would be unreliable.
The series is organised into three base models — RQR15, RQR20 and RQR40 — each offered in multiple sub-variants to address different installation and circuit requirements. The RQR15A is a 30W terminal-type variant covering 0.01Ω to 30Ω, while the RQR15L is a 15W lead-type variant extending from 30Ω to 54kΩ; together they give the RQR15 platform a continuous span of 0.01Ω to 54kΩ at up to 30W. The RQR20 covers 0.01Ω to 20kΩ at 20W in a compact terminal-type body. The RQR40 and RQR40L handle 40W across 0.01Ω to 54kΩ, with the RQR40L variant in lead form covering the upper resistance range from 10Ω to 54kΩ.
A notable feature of the RQR15 and RQR40 platforms is the availability of three-resistor network variants — the RQR15C and RQR40C — which house three independent resistive elements within a single ceramic enclosure. The RQR15C provides three 5W elements and the RQR40C provides three 10W elements, each covering 0.01Ω to 18kΩ. These network variants deliver significant advantages in space-constrained designs: three separately accessible resistors in a single package reduces the PCB area and component count compared to mounting three discrete cement resistors, while the shared enclosure ensures all three elements experience identical thermal and environmental conditions, aiding matching and long-term drift consistency.
Across the series, tolerance grades of ±0.5%, ±1%, ±2%, ±5% and ±10% are available, and the TCR is ±260ppm/°C maximum — the same grade used across the standard RQR and RQA families. The operating temperature range is −55°C to +155°C. The dielectric withstanding voltage of AC 1500V for one minute with a maximum leakage current of 2mA confirms suitability for industrial line-voltage environments. Insulation resistance is a minimum of 20MΩ. The terminal-type variants are designed for direct screw or clip connection, supporting panel-wiring installations, while the lead-type L variants are suited to through-hole PCB assembly. The low cost and ease of installation inherent in the cement enclosure format make the RQR15/40 a practical solution for high-power board-level and panel-level resistive applications.
RQR15/40 Series High-Power Ceramic Encased Resistors Specifications
A practical overview for engineers and procurement teams evaluating resistive solutions.
Model: RQR15/40
Resistor type: Wire wound
Description: Ceramic encased
Power Rating: 15W~40W
Resistance (Ω): 0.01~54k
Tolerance (%): ±0.5, ±1, ±2, ±5, ±10
TCR (ppm/C): 260 (max.)
Applications of the RQR15/40 Series High-Power Ceramic Encased Resistors
Where RARA wire wound resistors are deployed in the field.
High-power industrial control panels — discharge resistors, voltage dividers and current-limiting elements in motor starters, variable-frequency drive panels and soft-starter assemblies where power ratings of 15W to 40W are required in a compact ceramic-encased form that withstands elevated enclosure temperatures
PCB-mounted network resistor applications — the RQR15C and RQR40C three-resistor network variants reduce component count and PCB area in circuits requiring multiple matched or related resistance values in a single footprint, including motor control feedback networks, multi-channel current limiting and resistive divider ladders
Power supply and UPS circuits — bleed resistors, pre-charge networks and inrush current limiters in industrial AC-DC power supplies, uninterruptible power systems and battery management equipment where sustained high-power dissipation demands a non-flammable, thermally robust enclosure
High-voltage discharge and snubber networks — the AC 1500V dielectric withstanding voltage supports use in series discharge paths, RC snubber networks and overvoltage clamping circuits in industrial converters, inverters and switchgear operating at line voltage
Motor drive and braking circuits — dynamic braking resistors and deceleration energy absorption elements in compact drive assemblies where the power density and mechanical robustness of the ceramic cement package allows direct PCB mounting at power levels that would otherwise require chassis-mounted resistors
Automotive and transportation auxiliary systems — high-power resistive elements in commercial vehicle HVAC systems, battery heater control circuits and auxiliary power management modules where the wide temperature range, vibration resistance and sealed enclosure support reliable service life in demanding vehicle environments
Renewable energy and energy storage systems — pre-charge resistors, balancing networks and protective discharge elements in solar inverters, battery management systems and energy storage installations where the combination of high power rating, wide resistance range and harsh-environment suitability of the RQR15/40 replaces multiple lower-power components
Telecommunications and infrastructure power equipment — load resistors, fault current limiters and protective network elements in base station rectifiers, DC power distribution systems and outdoor power cabinets where continuous high-power dissipation and resistance to humidity and temperature variation are operational requirements
Related Products of the RQR15/40 Series High-Power Ceramic Encased Resistors
Model: RQA
Resistor type: Wire wound
Description: Ceramic encased
Power Rating: 5W~20W
Resistance (Ω): 0.1~100k
Tolerance (%): ±5, ±10
TCR (ppm/C): 260, 400
Model: RQR
RResistor type: Wire wound
Description: Ceramic encased
Power Rating: 2W~12W
Resistance (Ω): 0.1~75k
Tolerance (%): ±5, ±10
TCR (ppm/C): 260, 400
Model: RQL
Resistor type: Wire wound
Description: Ceramic encased
Power Rating: 10W~40W
Resistance (Ω): 0.3~100k
Tolerance (%): ±5, ±10
TCR (ppm/C): 260, 400
Model: RQB
Resistor type: Wire wound
Description: Ceramic encased
Power Rating: 5W~20W
Resistance (Ω): 0.1~100k
Tolerance (%): ±5, ±10
TCR (ppm/C): 260, 400
Why Choose RARA Wire Wound Resistors
What sets RARA apart for engineers and procurement managers in industrial and automotive markets.
01
Widest Design Range
From 0.5W precision types to 12kW edge wound assemblies — one wire wound product family covering precision, ceramic-encased, fusible, non-flammable, and high-power variants.
02
Precision Available
The PWR series delivers ±0.1% tolerance and TCR as low as 20 ppm/°C — precision wire wound performance for instrumentation and measurement circuits.
03
Automotive Qualified
The AQL ceramic-encased series is AEC-Q200 qualified for automotive-grade reliability in EV battery management, HVAC, and powertrain applications.
04
Global Track Record
Trusted by Siemens, Rockwell, Toshiba, Schneider Electric, LG, and Hanwha — a customer base built on decades of consistent, certified performance.
