Asked — Edited

Connect Double H Bridge Drive


I bought a double H Bridge Drive, here :

H bridge on ebay

I saw this DJ's tutorial

DJ'S tutorial

But I don't understand how connect Ez Board and this H Bridge, because I don't Vcc port on H Bridge.

I did some testing, but I have only one engine running

Can you help me ?

Thank you.



Upgrade to ARC Pro

Experience early access to the latest features and updates. You'll have everything that is needed to unleash your robot's potential.

United Kingdom

I believe the +5V is the VCC on the H-Bridge. VCC on the EZ-B is 5V so it would make sense.


Vcc is your input voltage for the motors. +5V is power from the H-Bridge to the EZ-B. It can be enabled/disabled by jumper on the H-Bridge.

In the E-Bay auction pics Vcc is labeled +12V.



I don't understand, if I connect Vcc input voltage +5v on EZ-B or not, it's the same result. I have only the right motor works ! (and it works very good, but the left motor doesn't works) I reversed motors and it's the same result, only the right motor works). Some pictures for you of my mounting :

User-inserted image

User-inserted image

User-inserted image

I don't understand, why if I connect or not the +5v (Vcc), it's the same result ? why I have only the right motor works ?

Can you help me ?

Thank you



An another picture better User-inserted image



Where is your PWM line?

Have you connected it as per DJ's video?

Also, what are those motors rated for power?

They look quite big and might require more juice than the EZ-B power pack can supply.


1 = gnd 2 = +5 3 = ext

I have the same h bridge this is how I have it wired. to enable the PWM you have to take off the ena & enb caps and only wire it to the first pin

User-inserted image

User-inserted image



I'm not acquainted with this Motor Controller. However lets see if we can work through this.

First possible explanation: In your photo above I see the A and B enable pins. It looks like you only have a lead going from EZB to the B enable pin and appears to be the right motor now seems to be working for you. The diagram you drew above shows a jumper between A & B enable which you DO need to get both motors to start up. That way you only need one digital signal port on EZB and one PWM control set to that port in ARC to control the speed of both motors. Make sure you have that jumper installed and the lead going back to EZB is indeed on a digital signal port that is set properly in ARC.

Second possible explanation: This board is not able to be controlled by PWM. All you can do is enable or disable each motor using the jumper block.

Third possible Explanation: You have everything wired up properly and you have overloaded one side of the bridge and burnt it out. Did that side ever work? you can quickly blow one side of an H-Bridge by quickly reversing the direction of a DC motor. This controller is only able to handle a 2 amp load, (3 max). Start up amperage and quick reverse amps can be higher then what the specs are for the motor. Sometimes twice as high! So if your motor is pulling almost 2 amps and you quickly reverse, it may send up to 4 amps back into your control circuit. Is your controller is rated only for 2 amps you have a problem. To protect ageist this you need to buy a controller that already had over voltage and reverse protection or build a diode protection circuit that will draw off that fly back voltage to ground. I see there are indicator lights on the controller board. One light should come on for each direction and each motor. Is that happening?

One thing; I see different wiring in each of the pics you show. You need a ground connected between your power supply (the Negative) , EZB (Negative on it's power port) and your Controller (Power Ground between the 5v and 12v power input). I think if your using 5v from the EZB you need to remove the 5v enable jumper block. If your using the power pack you need the jumper block installed. This would also be the case if you use another type of external power supply like a 12v power converter. From the Ebay link you posted: "This module has a built-in 5v power supply, when the driving voltage is 7v-35v, this supply is suitable for power supply, DO NOT input voltage to +5v supply interface".

Another thing; Lumpy is correct, your motors may be to big for that little power pack. Consider using a different power supply that can supply more volts and amps. What are you going to use this in? Are you able to use a power converter you can plug into a wall? An old computer power supply is a good choice for bench testing. Once you get the bugs worked out you can find a proper battery set up that can provide dedicated power to only your motors. That way you can give 12v to your motors and 5v to your electronics through a step down board or EZB it's self.

Try this:After you have rechecked and rechecked and rechecked your wireing and power supply remove your motors from the controller. Attach a digital tester to see us your getting the voltage you expect both A & B output terminals. Don't hook up any motors till you get the power readings you expect. If you don't own and know how to use a tester now is the time to buy one and learn to use it. ;)

Good luck, Dave Schulpiug


@Lumpy I use 2 motors of windshield ice. I thank to use it with an another battery 12v. What's the PWM line ?

@derrick Thanks for your pictures. My error is definitely I don't use ENA and ENB, because I don't know what is it ? And how to connect it (which connector ? (link on web, please).

@dschulpius Thanks for your answer. In first, I'll test with smaller motors, and I'll see ...



No Jerome, Please reread my post. Do not attach and motors yet. Remove them and test for voltage. That's the only way your going to see if you are getting the proper voltage you expect. You should also see a different light on the controller board light for each direction and motor. Two motors, 4 lights. Are you seeing them light?

EDIT: Ahh, is see, I was looking at Derriks pic. You need to remove the jumper blocks put a jumper between Enable A and Enable B on your board. Attach the pin closest to the edge of the board. Enable is the same as PWM. If your board is PWM capable you will be able to control the speed of your motors with it by using the PWM slider in ARC. It just changes the voltage sent to the motors (actually it's more completed then that so go a Google search).


If those are windshield wiper motors, they can pull up to 5 amps each. You are going to need a bigger controller. Also, for what it is worth, I bought two motor controllers on Ebay. One worked, the other did not. I got the defective one replaced, but eventually all three stopped working. They were rated for 68 Amps. A lot of what you get on Ebay is defective.


sorry my post is probably confusing you more. the ENa & ENb are for the PWM all you need to do is pull the plugs off, and it will expose two pins. the closer pin to the edge of the board are the ones you need to solder a wire to. I use one wire on each of them so I can have two PWM "one for each motor". you have the in1-4 plugged in correctly but I see in your picture that you do not have the +5 going into the +5 on the ez-b "the middle pin", it looks like you have it going into ext... i.e the white wire.

excuse my soldering on this User-inserted image


thank you at all for your answers.

derrick, I understand better with your picture.

I will keep you informed of my tests in a few days.




Derrick, I did as you (thank you again). But I have already 1 motor works (right). I think, left connectors are out. There isn't volt on the left connectors !

Is it correct ? Left Trigger A : D8 (with D1, the motors doesn't work) Left Trigger B : D2 Right Trigger A : D3 Right Trigger B : D4

It's too late, i'll see that tomorrow.



Jerome, sounds like you have it wired probably have a bad hbridge, if you are not getting any voltage on the left side. Were you using a multimeter ? Left trigger a = d8 Left trigger b = d2 Right trigger a = d3 Right trigger b = d4 +5 = d5 middle +5 Ena = d6 trigger Enb = d7 trigger +12 & ground = battery + & -



Derrick, I had the same config of you. I use a multimeter, and I've 0 volt on the left motor.

I have a question : I use the control '4 wire HBridge Movement Panel' of ARC, and I can only indicate : Left trigger a Left trigger b Right trigger a Right trigger b Consequently, Use I the good control ? Where CAN I config ENA and ENB ? Can I to try a script (is it difficult ) ?



That's correct, the ena & enb are for the PWM control, take a look at the tutorial....

United Kingdom

PWM is simple to set up.

Assuming you have connected as the tutorial video using the 5th signal wire for both enable pins, add a PWM control and assign it to the port that is connected to the enable pins. The higher the PWM the faster the motors will spin.

You could use a script too using the PWM() command but why complicate what's simple?


I'm having with another H bridge. I wish you informed.

thank you for your help


Can you post a picture of your last wiring setupi?



VoilĂ  the last wiring User-inserted image

I have connected only the motor B (out B) and it's good with: In3 = D3 (ext) In4 = D4 (ext) ENB = D6 (ext) / config in PWM +5v = D16 (+5) ==> my motor works very good

If I connected only the motor A (out A) and it's bad with: In1 = D1 (ext) In2 = D2 (ext) ENB = D7 (ext) / config in PWM +5v = D16 (+5) ==> my motor doesn't work (not even a noise)

Part A out is defective. It seems to me that this card can suporter two engines windshield ice. I just order another

H Bridge



Great, that's how it should be wired!, nice job...its a shame your hbridge is faulty.


Yes, Looks good. Keep your head up. I burnt up three H-Bridges before I got everything working.

Keep in mind you may beed a more heavy duty H-Bridge then what you ordered. Pololu has some nice ones that will work at a good price. You'll need to know how many amps your motors pull and the operating voltage.


Hi.. So if I get it rigth, if I want to use a diferent power source only for the motors, I should wire that to the Vcc and ground on the h-bridge, Is that correct? And do I need to connect the 5v To Ez-B too? Thanks...

United Kingdom

I just fitted one of these to Jarvis

Basically, 5 signal wires, D15 to D19 to each of the In1-In4 plus PWM split to both enables. VCC from battery to VCC on H-Bridge Ground from D19 to H-bridge ground Vcc from D19 to H-Bridge 5V


I luv it when a problem is surrounded by great answers and generous people! bookmarked This thread is definately a goto for H Bridge issues/connections