Pololu Robotics & Electronics
My account Comments or questions? About Pololu Contact Ordering information Distributors

ACS709 Current Sensor Help!


I am using ACS709 Current Sensor. I want to measure the current voltage is 220-230 V AC. How do you tie the ends of the card J1? We also have one more question, will apply voltage end of the card number of the phase V (AC) should be??




As we say on the ACS709 current sensor’s product page, this product is intended for use below 30 V. Working with higher voltages can be extremely dangerous,and we only recommend doing it if you absolutely know what you are doing. From your questions, I think you should be seeking assistance from a qualified individual.

- Zeeshan


What do you mean dangerous? IP + and IP-220 V AC I hooked up in series, and no damage to the card. Phase I connected the load line “3 A” stands out, but VIOUT 2.30 V DC show and constantly changing.

I got the following file datasheet. Study says AC uses?



What I mean by dangerous is that voltages that high can kill you. While one with sufficient expertise can use this sensor at such voltages, we do not support using the ACS709 current sensor above 30 V.

Separately, the sensor’s output voltage corresponds to the instantaneous current, so the output will be an AC voltage when the input is an AC current. Please see the sensor datasheet for more information.

- Zeeshan


I am aware of the danger. I bought this card for nothing: (?
Do you have a recommendation?


As I said in my previous post, it is possible for someone with sufficient expertise to use the ACS709 current sensor in the way you want. From your questions, it seems very clear that you do not have the appropriate expertise (such as being able to understand how to use this sensor from its documentation), and we strongly discourage you from continuing with this project until you can find a suitably qualified individual to help you. (In short, we are not willing to help you with something that has a non-trivial likelihood of seriously injuring or killing you.)

- Zeeshan


Never mentioned anything but a matter of technique explained. So thank you. I myself own problem solved. Next time you take your card IC Allegro is not going to do the installation myself.


Hi, quick question, where did you apply the voltage in this card. I have this and I’m just not sure how to use it. Secondly, using proper protection and all, can I use it for voltage around 258V AC? Also, I understand how to play with these voltages but @Zeeshan , the sensor works properly at these voltages or does it malfunction at any specific voltage. What is the absolute maximum rating, not considering the 30V?

prototype pcb assembly



In order to measure current, you would want to insert the current sensor into your system so that the current you want to measure flows from IP+ to IP- (or vice versa), as shown on the product page. The IP leads are rated for continuous voltages up to 277 V as indicated by the datasheet, which can be found under the Resources tab on the product page. As I previously said in this thread, we do not support using the ACS709 current sensor above 30 V.

- Zeeshan