Using a 3-cell battery rated at 7.4 volts with your EZ-B v4 should generally be safe, as the EZ-B v4 is designed to handle input voltages from 4.5V to 16V. However, it's crucial to ensure that the voltage does not exceed these limits, as higher voltages can indeed damage the board and connected devices such as servos.

Regarding your servos, it's important to check the specific voltage requirements for each type of servo you are using. Many standard servos are designed to operate at around 4.8V to 6V. Operating a servo at a higher voltage than it's rated for, like 7.4V, can lead to overheating and potential damage, as you've experienced.

Here are a few steps to ensure safety and proper operation:

1. Check servo Specifications: Always verify the voltage specifications of your servos. If they are not rated for 7.4V, you should consider using a voltage regulator to step down the voltage to a safe level for your servos.

2. Monitor Battery Voltage: Keep an eye on the battery voltage to ensure it does not exceed the maximum rating for your EZ-B v4 and connected devices.

3. Use a Voltage Regulator: If your servos or other peripherals cannot handle 7.4V, using a voltage regulator can help provide the appropriate voltage levels, protecting your components.

4. Inspect Connections: Regularly check all connections for signs of wear, loose wires, or potential shorts that could cause overheating or damage.

5. Test with Caution: When testing new setups or configurations, start with short test durations under close observation to catch any issues before they cause damage.

If you need to replace the damaged servo or are considering upgrading to servos that can handle higher voltages, make sure to select ones that match the voltage output of your battery or use a regulator as mentioned. This will help prevent future incidents of overheating or damage.

Hello @Nomad, if you draw too much power through the EZ-Bv4 itself instead of wiring up a high torque servo to use external power there is the possibility that you could damage the EZ-Bv4 reverse polarity protection diode. This diode is located near the power input pins (micro deans connector) on the EZ-Bv4 main board. This diode can be replaced if it is damaged and you have the ability to surface mount solder.

hi jeremie

it looks sofar works averything . i dont have a clue why i bouth the 3 cell batterie 7.4 volts . so the special servo's dont give full range 30 to 178 . the big ones do have full range 1 to 180 .  its amazing i did use that batterie with HDD without any problems .

thank you

Couple things here,

3 cell LiPo Batteries are 11.1V not 7.4V. You could have a 2 cell or 4 cell 7.4V LiPo battery but not a 3 cell.

Depending on the servo, you may not usually get the full rang because ARC + the EZ-B uses the 568uS to 2148uS signal range. A lot of servos operate either outside of this range or they operate at a shorter pulse width range like 1000uS to 2000uS for example. This range is programmed within the firmware of the servo and can’t be changed without a servo programmer from the manufacturer.

so did i misread this batterie ?

it has a red dot on 7.4 volt?

these servo are programmed to have a biger range . bummer i bouth dat before 4 more . 1 to 205

https://www.servocity.com/hs-5765mh-servo/?sku=35765S10

With three wires coming off the balance port it’s indeed a 2 cell 7.4v

hi dj

ah that explain i could use HDD servo without any problems . am gessing i bought this one for the bigger servo's . so am not fully understand what happen whit that big servo then ? i also learned the page on servocity all big servo's pictures looks desame , but these are smaller . the 6 volts are the biggest . i didn read the sizes.

jeremie

ok 3 cell is 11.1 volts .

As DJ mentioned, you do have a 2-cell 7.4V battery and it looks like you have a larger servo that is 7.4V compatible so you have everything you need.

If you want to change the range, it seems that Servocity does sell a servo programmer for that servo: DPC-11 servo Programmer - ServoCity

the ones i bougth are re programmed to have a bigger range . 1 to 205 . i dont want to open the expencive servo  i was hoping to have , enough range for the turning waist inmoove .  so how got the servo  so hot then ?

jeremie

about post #2 here's a picture of the board . does it look ok ?

Looks ok to me, I don’t see any burn marks on the polarity protection diode.

hi jeremie

thanks for looking at the picture .

hi

is this a good voltage regulator for the 6 volt servo ? cost 20 euro for 2 pieces .

@Nomad that regulator seems pretty good! I've never used it but the specifications look good.

great thanks jeremie .