Products > GR02 DC Planetary Gearmotor

 (in 12V and 18V versions, up to 100W continuous power output)


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Motor Specifications with

Gearbox


(Select a gearbox ratio. Key values are highlighted in green)


Motor manufacturer ID

ADRS550SH

HRS-550S

Nominal voltage:

12V DC

18V DC

Operating voltage:

4-16V 6-25V

No-load speed (minimum):

19,000rpm 19,400rpm

No-load speed after gearbox:

795rpm 810rpm

No-load current:

1.4A 0.85A

Stall current*:

79A 68.6A

Max. efficiency current:

12A 8.5A

Max. efficiency power output:

85.0W 103.5W

Max. efficiency speed after gearbox*:

729rpm 700rpm

Max. efficiency torque:

470g-cm 600g-cm

Max. efficiency torque after gearbox*:

1.10Nm
1.41Nm

Stall torque*:

3750g-cm 5145g-cm

Stall torque after gearbox*:

8.83Nm
(0.93kg-m)
12.1Nm
(1.23kg-m)

*extrapolated value, excluding losses
All values given are for operation at the nominal voltage
Peak power output is greater than the max. efficiency value


Motor manufacturer ID

ADRS550SH

HRS-550S

Nominal voltage:

12V DC

18V DC

Operating voltage:

4-16V 6-25V

No-load speed (minimum):

19,000rpm 19,400rpm

No-load speed after gearbox:

520rpm 542rpm

No-load current:

1.4A 0.85A

Stall current*:

79A 68.6A

Max. efficiency current:

12A 8.5A

Max. efficiency power output:

85.0W 103.5W

Max. efficiency speed after gearbox*:

486rpm 468rpm

Max. efficiency torque:

470g-cm 600g-cm

Max. efficiency torque after gearbox*:

1.65Nm
2.11Nm

Stall torque*:

3750g-cm 5145g-cm

Stall torque after gearbox*:

13.2Nm
(1.35kg-m)
18.1Nm
(1.85kg-m)

*extrapolated value, excluding losses
All values given are for operation at the nominal voltage
Peak power output is greater than the max. efficiency value



Motor Operating Advice


It is recommended to 'break-in' a new motor and gearbox before use, this is done by running for 3-4 minutes continuously in both directions (polarity one way then the other) at a low voltage (usually around half the nominal voltage). This ensures that all of the gears and bearings are running freely before being subjected to loading and that the motor brushes are well seated on the commutator.

The motor is marked on one side of its rear with a red dot (a red lead will be connected to this side if you have chosen a lead option). If the this side is connected to the positive output of a DC power supply or battery and the other side to negative then the gearbox output will travel anticlockwise when viewed from the shaft end up towards the front aluminium face. To change motor direction swap the polarity so that negative output goes to the red marked side and positive to the other side.

All of the motors feature a built-in cooling fan and four radial air vents towards the rear of their bodies. These should be left uncovered to minimise risk of overheating - use mesh or a fine grill to provide some shielding if you're worried about dirt or objects entering the motor. If you fully cover these cooling vents you run the risk of overheating the motor and we cannot provide replacements for motor failures caused because of this.


Over-volting the Motor


It is possible to over-volt a DC motor beyond its nominal voltage to obtain a higher power (and speed and torque) output. Although we won't provide free replacements for items that fail due to over-volting, we can suggest that you follow a '1.5 times' rule when determining a ceiling for practical operation (to minimise risk of failure). This means that for a 12V motor you shouldn't exceed 18V otherwise the life-span will be significantly reduced unless operating with only very small loads for short time periods. The 'operating voltage' limits given in the motor specifications table above are provided on this basis.
    Motor cooling is especially important when over-volting so if doing so you should ensure the motor is well ventilated. Mounting onto a metal plate/structure can help with cooling provided there is a decent contact surface between the aluminium mounting blocks and the metal part.


Gearbox Loading


The maximum recommended load torque for the gearbox is 10Nm (1.02 kg-m), which they may exceed in some configurations. If running above this load you may run the risk of damaging gears and/or the gear carrier plates, as well as overheating the motor itself if a prolonged load. We are however prepared to offer discounts on replacement parts to previous motor customers if such problems arise due to overloading (as long as evidence of failure type can be provided).


Closeup of the second gearbox reduction stage
(with three 18T planet gears)


Closeup of the first reduction stage in the 24:1 version
(three 15T planet gears)




Discontinued
- Due to increases in supplier costs we have had to discontinue this item for the foreseeable future. The final stocks of the complete gearmotor have now been sold but we maintain stocks of spare parts available to all previous customers. Please contact us if you have any questions or need any spares for your motor.





The

GR02

is a second-generation planetary/epicyclic gearbox and DC (direct current) electric motor combination designed to provide a high power, compact and easily mounted drivetrain solution. It has been exclusively developed by Gimson Robotics and is available to buy online with UK-based stock.

  Key features of the motor:
  • Available with two motor versions (12V or 18V) and two gearbox versions (24:1 ratio or 36:1 ratio)

  • High power output, up to 100W continuous

  • Robust body, all aluminium and steel construction

  • Easy mounting to flat surfaces via ten M5 (5mm) threaded screw holes

  • Ideal speed and torque balance for use as a drive motor in robots and electric vehicles weighing up to 20kg. Drive wheels may be mounted directly to the gearbox output shaft


The motor is ideal for a wide range of applications, from robotics and automation through to special effects. The output shaft is 12mm in diameter and 42.5mm long from the front aluminium face.

All of the motor and gearbox options have the same body size. The gearbox options are either

24:1 ratio (for higher speed output)

or

36:1 ratio (for greater torque output)


The motors meanwhile are available with nominal operating voltages of

12V DC

or

18V DC


Please see the 'motor specifications' table in the left-hand column of this page for operating data.

A range of accessories and spares are available for the motor including spare motors and planet gears.


Gearbox Build Detail


Size:

40mm square, 145mm overall length (click on the below image to expand a fully dimensioned diagram)
GR02 dimensions, click to expand

Mounting:

Ten 5mm threaded holes.

Eight M5 x 7 holes

on the top and bottom of the aluminium blocks (four each side) placed on a rectangle of 18mm x 29.5mm. 

Two M5 x 6 holes

on the front face.
All have standard 0.8mm pitch threads

Body construction:

Two CNC milled 6061 aerospace grade aluminium body sections


The front section is 12mm thick, the rear section 10mm thick.
One sintered steel planetary ring gear.
Four M4 x 35 high tensile steel cap-head  screws (with 3mm hexagonal socket)


Gearbox type:

Planetary/epicyclic. Either

24:1

or

36:1

ratio, both options have two reduction stages: 4:1 then 6:1 for the 24:1 ratio or 6:1 then 6:1 for the 36:1 ratio. All-steel gears for maximum torque handling. Spare gears and other parts are available

Shaft construction:

From the front aluminium face: 12mm diameter 28.5mm long round section followed by a 14mm x 3/8" UNF thread section. An internal 5mm left-handed internal thread runs 20mm into the shaft from the far end which may be used in conjunction with the external thread to ensure an object mounted on the shaft does not unscrew itself. The outer threaded section fits standard sized 3/8" cordless/power drill chucks

Shaft support:

A single 12mm-bore steel ball bearing with rubber seals is housed in the front motor mount.

It is recommended that external shaft support (such as a second bearing) is used if running an overhanging load, especially if the load is placed over the 3/8" UNF threaded section towards the end of the shaft.


Spare motor shafts can be purchased here

Weight:

450g (excluding optional leads and fixings)


The motor is supplied fully assembled with the gearbox lubricated (with a lithium-based grease). A 20mm long M5 left-hand screw is included to fit the internal threaded bore at the end of the output shaft. Also included are a single 3/8" UNF nut and a 5mm penny washer to aid in mounting. These items may also be purchased separately if you require spares.



Motor Leads & Connector Options


The motor is available either with plain copper connecting tabs (as pictured in the product images, above left), or soldered 200mm long silicone insulated leads (black & red, click for image), or 100mm silicone insulated leads with a male 'Deans' type connector (a matching female connector will also be included in your order if you select this option, click for image).
All leads/connector options include heat-shrinking of soldered connections.






Discontinued

Due to increases in supplier costs we have had to discontinue this item for the foreseeable future. The final stocks of the complete gearmotor have now been sold but we maintain stocks of spare parts available to all previous customers. Please contact us if you have any questions or need any spares for your motor.