khimm19:
hmmm.. 3-4 hrs seems too fast.. can i use atx power supply(PSU) instead?
If that is a response to my Reply #2, I did not mean 3 or 4 hours. I meant 3 or 4 amp hours - of course if you are drawing 1 amp from the battery it amounts to the same thing. Unfortunately battery manufacturers are very optimistic.
septillion:
Hehe, that's true But from the size you can assume it's not very power hungry. I agree, not very scientific but will do for hobby standards (and more then you want to know for industry as well...)
Robin2:
If that is a response to my Reply #2, I did not mean 3 or 4 hours. I meant 3 or 4 amp hours - of course if you are drawing 1 amp from the battery it amounts to the same thing. Unfortunately battery manufacturers are very optimistic.
...R
how can i charge the battery if its attach in the barrel jack of arduino?
If you want to charge a 12volt SLA battery, then connect a 12volt SLA battery charger to it.
I always get nervous when powering an Arduino with more than 9volt (>= 13.5volt in this case).
The 5volt regulator on the Uno could overheat, depending on what else the Uno has to power.
You might want to power the Arduino with a 5volt buck converter (on the 5volt pin).
Leo..
Robin2:
That 12v 9Ah battery should be capable of powering everything. Lead acid batteries can usually supply high currents for short periods. But I can't say how long it will be until the battery needs recharging. I would assume 9Ah really means 3 or 4.
You can certainly connect the battery to the Arduino. However do NOT draw current for the other device through the Arduino.
...R
PS ... do not leave a lead-acid battery in a discharged state - it will greatly shorten its life.
so how can i control the servo motor and the HC-SR04 if i will not draw any current from other devices from arduino?
If you want to charge a 12volt SLA battery, then connect a 12volt SLA battery charger to it.
I always get nervous when powering an Arduino with more than 9volt (>= 13.5volt in this case).
The 5volt regulator on the Uno could overheat, depending on what else the Uno has to power.
You might want to power the Arduino with a 5volt buck converter (on the 5volt pin).
Leo..
khimm19:
so how can i control the servo motor and the HC-SR04 if i will not draw any current from other devices from arduino?
Powering the HC-SR04 from the Arduino 5v pin is probably OK, but not the servo.
If (as @Wawa has suggested) you use a 5v regulator to power the Arduino then you could also use that to power the Servo and the HCSR04. If it is a small servo the 500mA should be sufficient.
Robin2:
Powering the HC-SR04 from the Arduino 5v pin is probably OK, but not the servo.
If (as @Wawa has suggested) you use a 5v regulator to power the Arduino then you could also use that to power the Servo and the HCSR04. If it is a small servo the 500mA should be sufficient.
...R
i have posted my servo.. can u plss suggest what should i do to control it.. why cant i use the 5v pin of arduino to control it?
khimm19:
i have posted my servo.. can u plss suggest what should i do to control it.. why cant i use the 5v pin of arduino to control it?
When you say "control" presumably you mean "power", because you will control it with a 5V digital output; powering it is a different matter.
According to this page, that MG996R servo needs substantial current. When it's running it draws 500-900mA, but more to the point at stall it requires 2.5A. Stall current is what it draws for a short time each time it starts to move, and of course any time it actually jams.
So you need to provide at least 2.5A just for the servo.
juma_yetu:
When you say "control" presumably you mean "power", because you will control it with a 5V digital output; powering it is a different matter.
According to this page, that MG996R servo needs substantial current. When it's running it draws 500-900mA, but more to the point at stall it requires 2.5A. Stall current is what it draws for a short time each time it starts to move, and of course any time it actually jams.
So you need to provide at least 2.5A just for the servo.
so i cant use the 5v pin of arduino? so it means i need extra power supply just for the servo?
You can but I wouldn't The HC-SR04 is pretty low current and it likes a stable voltage. A servo is a beast when it comes to current which will probably make the 5V prone to having spikes and dips. Not a problem for the servo but it is for an IC. And because the HC-SR04 is low current you can connect it to the Arduino 5V which is decoupled from the servo and thus more stable.