L298n connecting in parallel

[Guorishix]

Hello! I would like to ask for some advice or help if my wiring is appropriate as shown in the photo. I am using 2 L298n motor drivers to actuate 4 peristaltic pumps (runs @400mA each, hence, 1.6A total max current when all pumps actuating). I am powering these modules using as 12V power supply in parallel and will be hooked to a Raspberry Pi microcontroller for control. I am wondering if such parallel connection would be ok and if are there any problems I might encounter since I it's my first time handling with motors for my small automation project. Thanks!

 

[kellys_eye]

I am wondering if such parallel connection would be ok

Providing the power supply can deliver the minimum required current you should be perfectly ok. Additional supply smoothing capacitors at the DC input of each board would help.

 

[Guorishix]

Providing the power supply can deliver the minimum required current you should be perfectly ok. Additional supply smoothing capacitors at the DC input of each board would help.

Alright! Thank you very much

 

[Alec_t]

Bear in mind that the start-up (stall) current of a DC motor will usually be several times its normal running current.

 

[Guorishix]

Bear in mind that the start-up (stall) current of a DC motor will usually be several times its normal running current.

I see. If I understood it right, you mean I would have to mitigate those spikes at startup and maybe use smoothing capacitors? Just like what the previous post suggested

 

[bertus]

Hello,

Why not use a higher power driver?
This one could handle it easy:
https://www.robotshop.com/nl/en/dc-motor-driver-2-15a.html

Bertus

 

[Guorishix]

Hello,

Why not use a higher power driver?
This one could handle it easy:
https://www.robotshop.com/nl/en/dc-motor-driver-2-15a.html

Bertus

Hello,

The L298N's a common driver which I think should suffice, i'm not sure if I could find those drivers you mentioned in our local area for reasonable price for my dosing application. Thank you for the recommendation though, will surely consider.

 

[bertus]

Hello,

As @Alec_t said, the start-up (stall) current can be much higher.
The start-up current can be upto 5 times the running current.
So 2 Amp for each pump.
Do you have details on the used pump?
Are there other currents given in the datasheet?

Bertus

 

[Guorishix]

Hello,

Do you have details on the used pump?
Are there other currents given in the datasheet?

Bertus

I couldn't find a direct datasheet, but here is a link of the device. 12V 5W INTLLAB peristaltic pump
https://www.amazon.com/INTLLAB-Peristaltic-Liquid-Aquarium-Analytical/dp/B0799DKLZ3?th=1

 

[bertus]

Hello,

I found this page:
https://www.aliexpress.com/item/32770860268.html?spm=a2g0o.store_pc_home.productList_581540402.pic_1
It looks it is a chinese company.
I also found this on the page:

• What Kind Of adapter is necessary to
  
  
  • 12 volt 1-2 A
  • it's just a DC motor
  • Solder and DC 12v

Bertus

 

[bertus]

Hello,

You could parallel two channels of the L298 to drive one pump:

The complete schematic would be this for the 4 pumps:


Bertus

 

[Guorishix]

hmm, so connect the two outputs on each side? initially it would have been +out1, -out2 and vice versa, in the above schem, where does the ground go?

 

[Guorishix]

so in this case, i'd have only either pumps active to drive enough current?

 

[bertus]

Hello,

Here I have the grounds connected:


Bertus

 

[Guorishix]

alright, i'll try this. thanks alot!