SEW BW039-012 Detailed Product Description

SEW BW039-012 is a small power braking resistor from the SEW BW series, specifically designed for 2.2–5.5kW servo/frequency conversion systems, used for quickly discharging the regenerated electrical energy of the motor, stabilizing the DC bus voltage, and protecting the power devices of the driver. It is suitable for applications with small inertia, frequent braking, and light-load energy consumption.

I. Basic Information

Product Series: BW Series Brake Resistor (Brake Resistor)

Full Model: BW039-012

Variant Model: BW039-012-T (Metal Mesh Cover, IP54 Protection)

Product Type: Wound-Resistor, Aluminum Shell Wave-Form Heat Dissipation, With Temperature Control Protection

Manufacturer: SEW-EURODRIVE (Germany)

Compatible Equipment: SEW MOVIDRIVE, BTS20, MOVITRAC, MDX61/60 Series Drives

Application Scenarios: Rapid Braking, Frequent Start/Stop, Light Load Hoisting, Small Inertia Equipment

Protection Grade: IP20 (Standard) / IP54 (-T Type)

Cooling Method: Natural Cooling (Optional Forced Air Cooling)

II. Model Meaning Interpretation

BW: Brake Resistor (Brake Resistor) Series

039: Nominal Resistance 39Ω (Ohm)

012: Rated Power 1.2kW (1200W)

III. Core Technical Parameters

1. Electrical Parameters

Rated Power (PR): 1.2kW (Continuous, 100% ED)

Peak Power (PP): 12kW (Short Time, 10s, 10% ED)

Nominal Resistance (R): 39Ω ±5%

Voltage Rating: 800V DC (Compatible with 300–600V DC Bus)

Insulation Class: F Grade (155℃)

Temperature Switch: Built-in Normally Closed 85℃ Temperature Control, Overheating Cut-off, Linked Driver Alarm

Maximum Temperature Rise: 375℃ (Resistance Wire)

Enclosure Temperature: ≤120℃ (Safe Contact)

2. Physical Parameters

Package: Aluminum Shell Wave-Form Heat Dissipation (BW039-012) / Metal Mesh Cover (BW039-012-T) 

Dimensions (W×H×D): Approximately 250×180×120mm

Weight: Approximately 3.18kg

Installation method: Wall-mounted, vertical installation

Connection terminals: 2×M6 screw terminals

3. Environmental characteristics

Operating temperature: -25℃ ~ +45℃

Humidity: 5–95% (no condensation)

Vibration resistance: Industrial grade, suitable for machine tools, conveying equipment

Life: 10,000 hours (full load)

4. Functions and advantages

1. Low-power precise braking

1.2kW/39Ω: Suitable for 2.2–5.5kW servo / variable frequency systems

Peak 12kW: Satisfies small inertia, frequent braking, light load lowering

Low-inductance design: Does not interfere with servo control, precise positioning

2. Safe and reliable

Dual protection: 85℃ temperature control switch + high insulation and withstand voltage

Industrial-grade material: High-temperature resistant resistors, corrosion-resistant casing

Long life: Solid-state resistors, no aging, maintenance-free

3. Strong adaptability

SEW original: Directly compatible with MOVIDRIVE, BTS20, MDX60 series

Voltage compatibility: 300V/600V DC bus is universal

Installation flexibility: Vertical installation, forced air cooling optimization, multi-unit parallel expansion

4. Maintenance convenience

Status monitoring: Temperature control switch connected to the driver's BRK terminal

Replacement convenience: Standard size, direct substitution of the same specification resistors

No maintenance required: No consumables, long-term stable operation

Five. Typical applications

Applicable power: 2.2–5.5kW variable frequency / servo drives

System configuration: Driver + BW039-012 + servo / variable frequency motor

Typical conditions:

Small machine tool spindle, servo shaft braking

Light-load lifting platform, parking garage, conveyor

Small fan, pump with small inertia equipment emergency stop

Packaging, printing, textile equipment frequent start-stop, forward and reverse rotation

Six. Selection and installation tips

Power matching: Braking power ≤ 1.2kW (continuous)

Resistance matching: Recommended for driver's braking unit 39Ω

Voltage matching: DC bus ≤ 600V DC

Heat dissipation: Vertical installation, spacing ≥ 50mm, forced air cooling is better

Connection: Short, thick, straight wiring (≥ 4mm² cable), reduces voltage drop and interference

Protection: Temperature control switch connected to the driver's BRK terminal to achieve overheat protection

Seven. Order information

Model: BW039-012 (aluminum case, IP20)

Variant: BW039-012-T (net cover, IP54)

Order number: 8216894

Warranty: 12 months

Standard equipment: Resistor body, installation screws, temperature control switch wire

Eight. Comparison of the same series

BW012-050: 1.2kW / 50Ω (suitable for 2.2–5.5kW)

BW033-012: 1.2kW / 33Ω (suitable for 2.2–5.5kW)

BW039-012: 1.2kW / 39Ω (current) (suitable for 2.2–5.5kW)

BW018-035: 3.5kW / 18Ω (higher power)