External BEC or ESC Upgrade?

[Mongol Pete]

Greetings Crawler Gurus,

I will soon build my first RC scale crawler, the ECX Barrage v2 kit. As suggested by many, I will upgrade to a metal gear servo, this $16 JX brand waterproof model with decent torque

https://www.rcjuice.com/servos/servos/standard/jx/jx-servo-dc-5821lv-standard-digital-servo-high-torque-waterproof.html.

My question is, will I be better off installing an external BEC, or should I just upgrade to a better ESC, like a HW 1060 for $20 or a HW 1080 for $40?

Thanks for your advice,
MP

 

[crawlhog]

go with the BEC , the BEC in a ESC are useless. The external BEC is adjustable in case you decide to get a stronger servo

 

[Mongol Pete]

Thanks. Can you recommend a waterproof one please? Also, how are BECs installed?

 

[crawlhog]

go with the castle creation BEC, as far as I know no BEC is waterproof I just seal mine with a piece of shrink tubing before I install it. It gets hooked up to(soldered) the leads on your battery. MAKE SURE you disconnect the red signal wire from your ESC ( very important) . also the BEC comes with instructions, if you have any problems e mail me and ill walk you thru it

rb

 

[Smokin' Joe]

The hobbywing 1080 would have no trouble with that servo. It has an adjustable voltage switch mode BEC built in. There are a couple threads about it in the electronics section. Some people in those threads claim to be using some pretty high powered servos without an external BEC without issue. It would be more expensive than just getting an external BEC, but does have other features that may make it worth your while.

 

[Nastyman211]

Agree with crawlhog. Here is the link to crawler creation BEC 2.0, its being advertised as waterproof.

http://www.castlecreations.com/en/cc-bec-2-0-waterproof-voltage-regulator-010-0153-00


Sent from my iPhone using Tapatalk

 

[Mongol Pete]

Thanks a lot for the replies guys. For $40, I think I'd go with a HW 1080 ESC rather than that Castle waterproof BEC. I'll see how it goes...

 

[JatoTheRipper]

the BEC in a ESC are useless

Well this simply isn't true.

Some ESCs have garbage BECs. Castle made this famous. They have since gotten it together and the BEC in the X series is great. You simply do not need an external BEC for most applications.

The HobbyWing WP 1080 is a brushed ESC that does not need a BEC.

 

[HDMM]

The HW WP 1080 is a great little ESC, I use them in all sorts of projects. Never had and BEC issues with them.

 

[Jim85IROC]

For most people, the BEC in a decent ESC will be fine. An external BEC is beneficial in 2 situations:

1. You drive like a madman with a very powerful current sucking servo and the internal BEC is inadequate

2. You have a servo that performs best at a voltage level that your ESC's BEC can't provide.

To be honest, I think #2 is the most common reason why some could benefit from a BEC. I added a 959v2 servo to my Redcat and it works great on the WP1040's internal BEC. No brownouts so far. BUT... I'd like to bump the voltage up to 7-8V, which I can't do without a BEC unless I want to spend money on a new ESC. For that, a BEC is helpful.

 

[Smokin' Joe]

For most people, the BEC in a decent ESC will be fine. An external BEC is beneficial in 2 situations:

1. You drive like a madman with a very powerful current sucking servo and the internal BEC is inadequate

2. You have a servo that performs best at a voltage level that your ESC's BEC can't provide.

To be honest, I think #2 is the most common reason why some could benefit from a BEC. I added a 959v2 servo to my Redcat and it works great on the WP1040's internal BEC. No brownouts so far. BUT... I'd like to bump the voltage up to 7-8V, which I can't do without a BEC unless I want to spend money on a new ESC. For that, a BEC is helpful.

A third reason would be because your receiver can't handle the higher voltage even if your ESC's internal BEC can deliver it. For example, the HW 1080 can deliver 7.4 volts via it's internal BEC. If your receiver can only handle 6 volts then you can't safely utilize this feature. You could upgrade your receiver or use an external BEC (or a battery) with a receiver bypass to get around this.

 

[Jim85IROC]

Good point. I'd forgotten about that. In that case, you could also use an inexpensive buck converter to drop the voltage going to the receiver. In most cases, that's a lot cheaper than buying a $20 BEC to keep the receiver happy.

 

[Mongol Pete]

For most people, the BEC in a decent ESC will be fine. An external BEC is beneficial in 2 situations:

1. You drive like a madman with a very powerful current sucking servo and the internal BEC is inadequate

2. You have a servo that performs best at a voltage level that your ESC's BEC can't provide.

To be honest, I think #2 is the most common reason why some could benefit from a BEC. I added a 959v2 servo to my Redcat and it works great on the WP1040's internal BEC. No brownouts so far. BUT... I'd like to bump the voltage up to 7-8V, which I can't do without a BEC unless I want to spend money on a new ESC. For that, a BEC is helpful.

I found a Hobbywing external BEC on ebay for $3 so I'll learn how it helps, or if it helps with both my Barrage and my son's ECX Amp, which will both run upgraded servos.

Thanks for the replies.

 

[Ninomaniac]

That's a 3A BEC, dude. Same as in many or most ESCs.

 

[Mongol Pete]

Thanks Nino,

Both ESCs I will run are 5V internal BEC whereas this BEC is 6V. I don't know how these work yet, but I am pretty sure these will get better performance out of the servos.

 

[Ninomaniac]

That's true. And you'll remove some heat from the ESC's too. I burned a nice sensored Trackstar ESC by overloading its bec with a powerful servo. :/

 

[Mongol Pete]

I have the HW 1080 coming for the Barrage, which means the Amp gets the 60A Dynamite. I am planning to still run the HW UBEC on both because from what understand to this point, they can only help, not harm.

 

[allanon1965]

The voltage is not the big issue here, its the amperage. The castle BEC is 10 AMPs where the HW is 3 AMPs, which is what most inexpensive ESC's have for their internal BEC's. It wont take much servo load to overload a 3 AMP BEC, internal or external. The castle BEC is adjustable on the voltage as well, and can go over 7 volts.

 

[Mongol Pete]

The voltage is not the big issue here, its the amperage. The castle BEC is 10 AMPs where the HW is 3 AMPs, which is what most inexpensive ESC's have for their internal BEC's. It wont take much servo load to overload a 3 AMP BEC, internal or external. The castle BEC is adjustable on the voltage as well, and can go over 7 volts.

Thanks.

So, I guess the best option for me would be to power the servos with the HW BEC directly. I'll have to take a look at it once I have everything in front of me.

 

[durok]

Hobbywing BEC puts out 3A, if I recall correctly