DSSERVO BLS3245 Black Brushless Digital Servo, 45kg Class

Description

BLS3245 brushless servo by DSSERVO is a black, 45kg-class digital servo for RC car steering and robotics. The newer black-version manufacturer datasheet lists 43 kg·cm stall torque at 7.4 V and 49 kg·cm at 8.4 V. These are locked-shaft figures; they are not continuous operating torque ratings.

Brushless drive, metal gear train and IP67

The BLS3245 uses a brushless motor and double bearings. Product illustrations identify stainless-steel gears, an aluminum middle shell, waterproof gaskets and top and bottom covers. The black-version datasheet states IP67 waterproof performance. Treat IP67 as the manufacturer’s stated rating for the servo; protect the connector and cable entry in the installed system and do not assume the complete vehicle or robot is waterproof.

Torque, speed and current

The datasheet’s stated operating voltage range is 5–8.4 V. Its electrical table also includes a 4.8 V test column; because that is below the stated range, this listing does not recommend 4.8 V operation. At 8.4 V the listed stall current is 6.2 A, so choose a receiver BEC or regulated supply that can handle the expected load and current peaks. Do not power the servo from a microcontroller GPIO pin. No-load speed is measured without mechanical load.

Dimensions and mounting

The newer black-version datasheet lists a 40 × 20 × 37.5 mm body, 60 g net servo weight, 361:1 gear ratio, double bearings and a 300 ± 5 mm connector lead. Its drawing shows 54.5 mm overall mounting-tab width, a 49.5 mm mounting reference and 42.5 mm maximum height including the output spline. Check the supplied drawing against your mounting holes, available enclosure clearance and horn spline before ordering.

The product graphic depicts an output gear, stainless-steel gear train, aluminum middle shell, waterproof gaskets, bearings and covers. Mount the tabs without distorting the housing, and set linkage endpoints so the mechanism does not bind or press the servo against a mechanical stop.

PWM control and wiring

The servo uses PWM position control with a 500–2500 µs pulse range, 1500 µs neutral position, 2 µs deadband and a listed 50–330 Hz operating frequency. The manufacturer diagram shows 180° or 270° travel across the pulse range; actual travel depends on configuration and controller endpoints. The datasheet lists counterclockwise rotation for the stated pulse range. Verify direction and travel before connecting a constrained steering linkage or robot joint.

The wiring diagram identifies a JR-style 3-pin, 2.54 mm connector. The pictured cable versions use brown or black for ground, red for positive supply, and orange or white for signal. Confirm the actual connector polarity and wiring diagram before applying power; wire colors can vary by production version.

Applications and setup

The product graphic lists 1:8, 1:10 and 1:12 RC cars. The BLS3245 may also suit robotics when its dimensions, torque, speed, supply capability, spline and travel match the design. Vehicle mass, tire grip, steering geometry, horn length and linkage friction affect the required torque. Select the servo based on the actual load rather than the 45kg class label alone.

For setup, use a supply within the stated 5–8.4 V range, test direction and endpoints with the linkage disconnected or unloaded, and ensure the mechanism clears both travel limits. Avoid prolonged locked-shaft operation and provide adequate supply capacity, especially when multiple servos share a BEC.

Package contents

The quotation’s package field lists one digital metal servo, one 25T adjustable metal servo arm and one accessory set as pictured, but labels the servo DS3245 rather than BLS3245. The images show the included horn and mounting parts but do not confirm exact quantities. Confirm the model name and package contents before relying on a particular arm, screw or accessory quantity.

Frequently asked questions

Which specification revision is used? This listing follows the newer black-version datasheet revision. An older black datasheet and one supplied mechanical-specification image list different body height and gear ratio; the outdated image is excluded from the gallery.

Why is 4.8 V shown in the datasheet? The black datasheet’s electrical table includes a 4.8 V test column, while its operating range states 5–8.4 V. This listing follows the stated operating range and does not recommend using 4.8 V as the supply voltage.

Does the servo deliver 45 kg·cm at every voltage? No. The newer black-version electrical table lists 43 kg·cm at 7.4 V and 49 kg·cm at 8.4 V under stall conditions. Torque changes with voltage.

Can I assume 180° or 270° travel? The manufacturer diagram shows both ranges; actual travel depends on servo configuration and controller pulse endpoints. Check the mechanism before installation.