For a home pet project I want to wire up an electro motor to a Raspberry Pi. I want to constantly reverse the direction of the motor (meaning I want to be able to change the direction of the motor about every second). As far as I understand this can only be done with brushed DC electro motors. Since I need quite some power, I was thinking of buying

1. Motor

this electro motor, which is described as:

200W DC motor is reversing 24V speed control motor 1800 rpm high torque micro motor

enter image description here

2. Battery pack

I then want to wire it up to this LiPO battery pack, which has the following description:

Output voltage:12V-24V
Input voltage: 12.6V
Input current: 1AH-2AH
Output current: Max. 6AH
Output power: Max. 110WH
Material: Li-polymer for PHILIPS 2900MAH batteries 
Capacity: 52000MAH(3.7V)


@MarceloEspinozaVargas told me in his answer that the battery pack has a regulator which is too weak. So how about I buy two of these battery packs (2*12V), serially linking them up so that I get 24V, and then using this regulator, which says it is a DC-DC Automatic Boost Buck Converter 8V-30V to 2V-16V 6A 80W CC/CV Voltage Regulator charging 5v 12v 24v 19v Car power supply. Would that work you think?

3. H-Bridge

I then want to use this H-bridge for reversing the motor direction, which comes with the following info (description below picture):

enter image description here

Double BTS7960 43A H-bridge High-power Motor Driver module:
BTS7960B H-bridge 43A high-power motor driver Module Overview:
This driver uses chips BTS7960 composed of high-power drive full H-bridge driver module 
with thermal over-current protection. Double BTS7960 H-bridge driver circuit, with a 
strong drive and braking, effectively isolating the microcontroller and motor driver! 
High-current 43A

Double BTS7960 large current (43 A) H bridge driver;
5V isolate with MCU, and effectively protect MCU;
5V power indicator on board;
voltage indication of motor driver output end;
can solder heat sink;
Just need four lines from MCU to driver module (GND. 5V. PWM1. PWM2);
isolation chip 5 V power supply (can share with MCU 5 V);
size: 4 * 5 * 1.2 cm;
Able to reverse the motor forward, two PWM input frequency up to 25kHZ;
two heat flow passing through an error signal output;
isolated chip 5V power supply (can be shared with the MCU 5V), can also use the on-board 5V supply;
the supply voltage 5.5V to 27V;

My Question

Before spending the money on it, I want to be sure that this combination will actually work. I mean; does that seem like a good battery pack for that motor, and can the H-bridge I link to handle the power going through? I see the H-Bridge says

I'm just a bit insecure about spending all this money when it's not going to work. So all tips are welcome!

  • \$\begingroup\$ I don't speak Spanish very well so the link is fairly useless to me but I would urge you to NOT buy anything that doesn't have a recognizable data sheet and a recognizable supplier. As for "constantly reverse the direction of the motor" you need to define this in a much more clear cut way. \$\endgroup\$
    – Andy aka
    Feb 10 '17 at 10:51
  • \$\begingroup\$ @Andyaka - Which website opens in Spanish for you? All of them open in English for me. About the constantly reverse the direction of the motor; I mean that I want to be able to change the direction of the motor about every one or two seconds to balance something. \$\endgroup\$
    – kramer65
    Feb 10 '17 at 11:07
  • \$\begingroup\$ Motor: 200 W motor de la CC es de marcha atrás 24 V de control de velocidad del motor 1800 rpm high torque micro motor \$\endgroup\$
    – Andy aka
    Feb 10 '17 at 11:24
  • \$\begingroup\$ Data sheets are needed, not buying pages. \$\endgroup\$
    – Andy aka
    Feb 10 '17 at 11:24

Based on your last edit, your battery pack is not a 12V battery, it's an array of 18 3.7V cells that give you 54000mAh with 3.7V output, the regulator it has is actually a step up regulator, so it converts your 3.7V in a 12-24Vdc, what you would need us a step up regulator that can boost 3.7V into 24V with at least 20A

  • \$\begingroup\$ Alright thank you very much. I just added a different suggestion for a regulator under Edit under point 2. Do you think that would work? And do you think the H-bridge is ok? \$\endgroup\$
    – kramer65
    Feb 10 '17 at 14:10
  • \$\begingroup\$ The H Bridge seems OK, but I don't think it could handle that much power (24V*20A aprox 480W) without a cooling fan at least. \$\endgroup\$ Feb 10 '17 at 14:14
  • \$\begingroup\$ For the new battery pack, it's a 12V 4.8Ah LiIon pack, so the max amount of current you could get from them is 4.8A, since it doesn't tell the maximum discharge capability we asume a 1C of discharge. You might look for battery packs for RC that are capable of release 20C to even 100C of discharge ratio \$\endgroup\$ Feb 10 '17 at 14:16
  • \$\begingroup\$ Alright thank you. I'll look for one. And do you think the H-bridge is ok for the motor? \$\endgroup\$
    – kramer65
    Feb 10 '17 at 14:17
  • \$\begingroup\$ It looks OK, I'll check the datasheet of the BTS7960 (you should take a look too robotpower.com/downloads/BTS7960_v1.1_2004-12-07.pdf) and come with a better answer \$\endgroup\$ Feb 10 '17 at 14:28

Based on the products description, the motor can easily draw more than 13A when using with load, that exceeds a lot the maximum current of your regulator (6A), besides the motor description doesn't show the stall torque and current, and it might be a lot more than 13A, so that regulator is not going to drive the motor unless the motor carries an extremely low load (in which case you'd better go for a smaller motor)

  • \$\begingroup\$ Thank you for your answer. So how about I use a different battery pack with a different regulator which can handle a higher Amperage. I added a description above in my question under point 2. Do you think that would work? \$\endgroup\$
    – kramer65
    Feb 10 '17 at 14:09
  • \$\begingroup\$ You're always welcome. I posted another answer to this question, check it. \$\endgroup\$ Feb 10 '17 at 14:10

Since you are actually going to buy something, buy a professional servi drive with a servo motor. It will be so much more fun! If you need something cheap, take qs9 from here:http://www.adtechen.com/news/QS9-Series-High-performance-Servo-Drives.html. i think it's best calue for money- chinese servo with world level performance.

  • \$\begingroup\$ Thank you for your suggestion. Any idea where I can buy those online? \$\endgroup\$
    – kramer65
    Feb 10 '17 at 14:17
  • \$\begingroup\$ This specific device- probably only from Adtech website. But there are more. \$\endgroup\$ Feb 10 '17 at 17:38
  • \$\begingroup\$ But a servo motor is going slow, but with a lot of torque right? I need at least 1000rpm, so I don't think a servo motor is good for me. Or am I wrong and can a servo motor actually do a high rpm as well? I'm all up for buying something professional, but I have no clue which ones are professional, so any more tips or links are welcome! \$\endgroup\$
    – kramer65
    Feb 11 '17 at 9:30
  • \$\begingroup\$ Not sure about servo at tour place, thus specific worked well on 10000rpm in my lab. \$\endgroup\$ Feb 11 '17 at 9:31
  • \$\begingroup\$ You probably refer to stepper, it's something different \$\endgroup\$ Feb 11 '17 at 9:31

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