CHIHAI GM12-N20 Hall Encoder DC Gear Motor

Overview

The CHIHAI MOTOR GM12-N20 combines a compact DC gear motor with an AB incremental Hall encoder. Select the motor voltage and A06/A12 winding, reduction ratio and motor-only or mounting-bracket package. The encoder provides feedback for compatible position and speed-control electronics.

Features

Metal reduction gears and enamelled copper armature windings.
3 mm D-shaped output shaft with a 2.5 mm flat reference.
Two-channel Hall feedback with a 7 PPR motor-shaft base resolution.
Onboard pull-up shaping resistors and a six-position connector.
Matching cable included; optional white mounting bracket.
1000:1 option with an extended gearbox, separate from the standard nine-ratio dimensional and performance references.

Specifications

Specification	Value / scope
Brand / model family	CHIHAI MOTOR / GM12-N20 Hall-encoder geared DC motor
Motor options	3V A06;6V A06;6V A12;12V A12 — select the required voltage and winding
Selectable nominal ratios	10,20,30,50,100,150,210,298,380 and 1000:1
1000:1 configuration	Extended gearbox; standard drawing and nine-ratio performance tables do not specify its length or operating points
Transmission / windings	Metal reduction gears /enamelled copper armature windings
Output shaft	3 mm diameter, +0/−0.03 mm; D-flat2.5 mm, +0/−0.1 mm
Shaft projection	10.0 ±0.3 mm
Standard drawing references	9 mm gearbox;0.7 mm front offset;22.0 ±1.0 mm motor/encoder section;12.2 mm maximum rear profile
Front drawing references	18.0 ±1.0 mm ×12 mm;10 mm and 9 mm hole-pattern references;two M1.4 andtwo M1.6 hole callouts
Front register reference	4 mm diameter
Motor weight	Approximately13 g for the standard gearbox reference; varies with ratio and does not establish the extended 1000:1 assembly mass
Encoder type	AB two-channel incremental magnetic Hall encoder
Encoder supply	3.3V DC or5V DC; separate from motor supply
Encoder output	A/B square-wave signals; onboard pull-up shaping resistors
Interface / cable	ZH1.5-6PIN connector; matching cable included
Encoder response frequency	100 kHz
Motor-shaft base resolution	7 PPR
Magnetic ring	14 poles /7 pole pairs
Output pulse relationship	7 PPR ×actual mechanical reduction ratio; rounded nominal ratios need not give the exact output pulse value

Encoder Wiring and Power

The following connector order is top-to-bottom in the illustrated encoder-board orientation. Use the board labels and drawing to orient the connector; do not infer pin functions solely from cable colors.

Terminal in illustrated order	Function
M2	Motor supply terminal
VCC	Encoder positive supply input
C2	Encoder channel B
C1	Encoder channel A
GND	Encoder supply return
M1	Motor supply terminal

Motor supply connects to M1/M2 and must match the selected 3V,6V or12V winding configuration. Encoder VCC uses 3.3V or5V DC with its GND return. The motor voltage range across different versions is not a universal voltage rating for every motor, and it is not the encoder supply rating.

Connect C1/C2 to compatible A/B counting inputs. Check the controller's input voltage, grounding and signal requirements. Pull-up resistors support compatible microcontroller inputs; they do not establish compatibility with every controller. A controller, counter or motor driver is not included.

Resolution and Output Pulses

7 PPR is the motor-shaft base resolution. The output-shaft pulse reference depends on the actual gearbox ratio; nominal ratio names may be rounded. Decoder counts depend on the counting method and should not be equated automatically with the listed pulse values.

Nominal ratio	Output pulses per revolution —12V A12 chart reference
10:1	67.76
20:1	135.5
30:1	206.3
50:1	357.70
100:1	695.1
150:1	1056.7
210:1	1468.3
298:1	2085.3
380:1	2654.1

No exact output pulse value is specified here for the extended 1000:1 option.

Electrical Performance References

Each table belongs to its stated voltage and winding. No-load, rated and stalled values describe different operating conditions. Do not combine them into a single simultaneous operating point, substitute data from another winding or run continuously at stall. The tables cover nominal ratios10–380; they do not specify the extended 1000:1 configuration.

12V A12 Winding

Nominal ratio	No-load current (mA)	No-load rpm	Rated torque (kgf·cm)	Rated torque (mN·m)	Rated rpm	Rated current (A)	Stall current (A)	Stall torque (kgf·cm)
10:1	≤60	2200	0.1	9.8	1000	≤0.22	0.4	0.15
20:1	≤60	1100	0.15	14.7	500	≤0.22	0.4	0.28
30:1	≤60	730	0.2	19.6	380	≤0.22	0.4	0.4
50:1	≤60	440	0.4	39.2	230	≤0.22	0.4	0.65
100:1	≤60	220	0.8	78.4	130	≤0.22	0.4	1.3
150:1	≤60	145	1.2	117.6	85	≤0.22	0.4	1.9
210:1	≤60	105	1.6	156.9	60	≤0.22	0.4	2.5
298:1	≤60	73	2.3	225.5	42	≤0.22	0.4	3.0
380:1	≤60	58	3.0	294.1	34	≤0.22	0.4	4.0

6V A12 Winding

Nominal ratio	No-load current (mA)	No-load rpm	Rated torque (kgf·cm)	Rated torque (mN·m)	Rated rpm	Rated current (A)	Stall current (A)	Stall torque (kgf·cm)
10:1	≤45	1000	0.05	4.9	700	≤0.1	0.2	0.07
20:1	≤45	500	0.09	8.8	350	≤0.1	0.2	0.12
30:1	≤45	330	0.12	—	200	≤0.1	0.2	0.2
50:1	≤45	200	0.2	19.6	120	≤0.1	0.2	0.32
100:1	≤45	100	0.4	39.2	65	≤0.1	0.2	0.7
150:1	≤45	65	0.6	58.8	45	≤0.1	0.2	0.9
210:1	≤45	47	0.8	78.45	30	≤0.1	0.2	1.2
298:1	≤45	33	1.15	112.75	20	≤0.1	0.2	1.5
380:1	≤45	26	1.5	147	17	≤0.1	0.2	2.0

6V A06 Winding

Nominal ratio	No-load current (mA)	No-load rpm	Rated torque (kgf·cm)	Rated torque (mN·m)	Rated rpm	Rated current (A)	Stall current (A)	Stall torque (kgf·cm)
10:1	≤60	1550	0.07	6.8	900	≤0.17	0.6	0.16
20:1	≤60	800	0.14	13.7	460	≤0.17	0.6	0.3
30:1	≤60	530	0.2	19.6	300	≤0.17	0.6	0.5
50:1	≤60	310	0.35	34.3	180	≤0.17	0.6	0.8
100:1	≤60	155	0.7	68.6	90	≤0.17	0.6	1.5
150:1	≤60	105	1.0	98	60	≤0.17	0.6	2.2
210:1	≤60	75	1.4	137.25	42	≤0.17	0.6	2.8
298:1	≤60	52	2.0	196.08	30	≤0.17	0.6	3.0
380:1	≤60	41	2.5	245.1	24	≤0.17	0.6	4.0

3V A06 Winding

Nominal ratio	No-load current (mA)	No-load rpm	Rated torque (kgf·cm)	Rated torque (mN·m)	Rated rpm	Rated current (A)	Stall current (A)	Stall torque (kgf·cm)
10:1	≤45	780	0.03	2.94	450	≤0.10	0.3	0.08
20:1	≤45	400	0.06	5.88	230	≤0.10	0.3	0.16
30:1	≤45	265	0.1	9.8	150	≤0.10	0.3	0.23
50:1	≤45	155	0.17	16.67	90	≤0.10	0.3	0.4
100:1	≤45	77	0.35	34.4	45	≤0.10	0.3	0.75
150:1	≤45	52	0.5	49.02	30	≤0.10	0.3	1.1
210:1	≤45	37	0.7	68.63	21	≤0.10	0.3	1.5
298:1	≤45	26	1.0	98.04	15	≤0.10	0.3	2.8
380:1	≤45	20	1.2	117.6	12	≤0.10	0.3	3.5

Mechanical Installation and Configuration

Check the 3 mm shaft,2.5 mm D-flat,10.0 mm projection reference and mounting-hole pattern against the mechanism. The standard drawing shows a9 mm gearbox section; the 1000:1 version uses a longer gearbox and must not be designed into that standard 9 mm envelope. Leave room for the encoder board, magnet, six-position connector and cable.

Support the gearbox and motor appropriately, avoid forcing the shaft and prevent overload or prolonged stalling. The white bracket is included only in the bracket package. A closed-loop control function requires suitable external electronics; the encoder does not itself provide a complete closed-loop controller.

Applications

For compatible small robot drives, balancing vehicles, inspection carts, home-robot mechanisms, camera positioning and compact automation drives requiring motor-speed or position feedback. The application image shows examples of motor-driven mechanisms. Match the selected motor to the required supply, load and mounting dimensions.

What's Included

Selected package	Contents
Encoder Motor	1 × selected geared motor with Hall encoder and matching six-wire cable
Encoder Motor + Mounting Bracket	1 × selected encoder motor,1 × matching cable and 1 × white mounting bracket

Each option contains one motor at the selected voltage, winding and reduction ratio. A power supply, motor driver, encoder counter and host controller are not included.

FAQ

Can the encoder use the same 12V supply as the motor?

No. Encoder VCC is specified for 3.3V or5V DC. Power the motor separately at the voltage of the selected winding.

Does 7 PPR mean7 output pulses per gearbox revolution?

No. It is the motor-shaft base resolution. Output pulses depend on the actual gearbox ratio and counting convention.

Why does the 10:1 reference show 67.76 output pulses?

The selector uses a nominal ratio name. The exact mechanical ratio can differ from that rounded label, so the listed output-pulse reference is not simply 7 times 10.