AQL Series AEC-Q200 Ceramic Encased Wire Wound Pre-charge Resistors
Automotive qualification — AEC-Q200 compliant; designed for EV, HEV, and PHEV power relay assembly inrush current control
Power ratings — 15W, 20W, 30W, 40W, 50W, 60W, 80W, and 100W (forced cooling or heatsink required at higher ratings)
Resistance range — 5Ω to 1kΩ depending on power rating; extended ohmic ranges available on request
Tolerance — ±5% (J class) across the full range
Temperature coefficient of resistance — ±260ppm/°C maximum
Operating temperature range — −55°C to +155°C
Dielectric withstanding voltage — AC 1500V for 1 minute (maximum leakage current 2mA)
Insulation resistance — 20MΩ minimum
Vibration and mechanical shock — Qualified to 10–20—Hz at 5g and 100G shock per automotive test conditions
RoHS — Compliant
What are the AQL Series AEC-Q200 Ceramic Encased Wire Wound Pre-charge Resistors?
The AQL is a range of automotive-grade ceramic encased wire wound resistors developed specifically for inrush current control through the Power Relay Assembly (PRA) in battery electric vehicles (EV), hybrid electric vehicles (HEV), and plug-in hybrid electric vehicles (PHEV). As high-voltage battery systems are connected to the drive inverter or onboard charger, the sudden energisation of large DC-link capacitors would generate destructive inrush currents without a pre-charge resistor in the circuit. The AQL is engineered to absorb this transient energy reliably and repeatedly across the full automotive temperature range of −55°C to +155°C, qualifying it as a safety-critical component in traction power systems.
The series is fully compliant with AEC-Q200, the automotive passive component qualification standard, which subjects components to an extended test programme covering load life, moisture resistance, thermal shock, temperature cycling, vibration, and mechanical shock. The AQL meets resistance change limits of ±[3%+0.05Ω] across all environmental stress tests, confirming stability under the harsh and cyclically demanding conditions of automotive underbonnet and battery enclosure environments. The operations test replicates real-world pre-charge cycling, with passing conditions defined for up to 15,000 charge cycles at 85°C and separate low-temperature qualification at −40°C, directly reflecting the duty cycle of a production EV powertrain over its service life.
Nine power ratings are available, from 15W to 100W, with the resistance range spanning 5Ω to 1kΩ depending on the model. Extended ohmic ranges are available on request for applications with specific impedance requirements. All variants carry a tight ±5% tolerance and a maximum temperature coefficient of ±260ppm/°C, ensuring that pre-charge current levels remain predictable across the full operating temperature range. At ratings of 40W and above, heatsink mounting or forced air cooling is required to maintain the component surface temperature within the rated operating band, and derating curves are provided to guide thermal design. Body dimensions scale with power rating, from a 48mm body at 15W up to 113mm at 80W and 100W, with mounting holes provided for secure chassis or bracket attachment.
AQL Series AEC-Q200 Ceramic Encased Wire Wound Pre-charge Resistors Specifications
A practical overview for engineers and procurement teams evaluating resistive solutions.
Model: AQL
Resistor type: Wire wound
Description: AEC-Q200, ceramic encased
Power Rating: 20W~60W
Resistance (Ω): 20~80
Tolerance (%): ±5
TCR (ppm/C): 260 max.
Applications of the AQL Series AEC-Q200 Ceramic Encased Wire Wound Pre-charge Resistors
Where RARA wire wound resistors are deployed in the field.
The AQL series is designed principally for pre-charge resistor duties in the Power Relay Assembly of battery electric, hybrid electric, and plug-in hybrid electric vehicles, where it limits inrush current during DC-link capacitor charging at system start-up. Beyond this primary application, the combination of AEC-Q200 qualification, wide power rating range, high dielectric strength, and broad operating temperature coverage makes the AQL suitable for a number of related automotive and industrial power electronics functions.
These include current-limiting resistors in onboard battery charger input circuits, discharge and bleed resistors in high-voltage DC bus networks, snubber and damping resistors in traction inverter assemblies, inrush protection resistors in DC-DC converter front-end stages, and protective series resistors in high-voltage measurement and monitoring circuits within battery management systems.
The series is also applicable to non-automotive industrial uses where AEC-Q200 qualification is valued as a proxy for extended reliability, such as in rail traction power converters, renewable energy inverters, and industrial UPS systems subject to demanding thermal cycling and vibration environments.
Related Products of the AQL Series AEC-Q200 Ceramic Encased Wire Wound Pre-charge 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: 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.)
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.
