Asked — Edited

Ez-B Keeps Disconnecting

So I finally got around to testing out my EZ-B. I have all my stuff plugged in, and as soon as I power it on, several of the items connected to it start running - without any controls associated. It connects up just fine but a soon as I attempt any control it disconnects. My thoughts are that because a couple of things are already running, as soon as I try to do anything else it is browning out. I am using the battery pack that came with it.

Thought: Should I disconnect all peripherals then power it up and slowly add items and test their control that way? Also, what would be an optimal battery pack to work with?


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#1  

what battery pack are you using , are you only using the parts that came with the kit? try hooking up only the board without any servos connected. sync your computers bluetooth first , once your connected disconnect power to board then connect your servos. many servo controllers ive seen in the past calibrate zero position when it powers on. maybe the servos that were moving were the modified ones?

#2  

Make sure you have the cables plugged in correctly. GND => Brown/Black 5+ => Red EXT => Orange/White if the cable is backwards the signal line will be tied low and when your trying to control them you would actually be changing the pwm on the GND line which could be causing the brown out Servos will move a bit initially when the power is connected I would always try connecting first before attaching devices

#3  

true , a misplaced ground will always do it but i kinda assumed bret would check it , he sounds savy ??

#4  

Items coming on at power up: el wire, cooling fan, secondary circuit flashing random leds. All of these are two wire devices (+5V and GND) Servos are all std movement and do the little jitter on initial power up, but nothing more. I have applied set controls to the el wire, cooling fan, and secondary circuit but they do not respond. I will re-check the ground but am sure that is correct. Thanks for your help.

PRO
Synthiam
#5  

@bret.tallent you can not power el wire or a cooling fan from the Signal Pin of the EZ-B. There is a section in the technical manual that explains it Click To Read

The EZ-B Signal Pin is signal, not power. It's used to "talk" to other devices. If you wish to control the power from a signal pin, you'll need to connect a switching transistor to the pin.

But, you have also given me a good EZ-Bit idea. I'm sending the first batch of EZ-Bit files off to the printer this week. I think we'll see the launch sometime next week or the week after, depends on the printing speed.

#6  

Thanks DJ. I am using the GND and +5V connections. The fan is a mini 5V fan and the the el wire is run through an inverter that normally uses USB power from a computer. So I was only looking at providing these two the 5 volts. Does this not work? Is the only way to provide 5v to peripherals through a switching transistor? What transistor would I need to use and how would I hook it up? Thank you.

PRO
Synthiam
#7  

@bret.tallent yeah that will work. I misunderstood and though you were powering from the Signal I/O line. If you are powering the units off the I/O it should be fine, but you may run out of current... depends how many devices you have hooked up.

Are you using the stock battery pack? If so, you will most likely need to upgrade to a battery source with more juice.

#8  

Okay, I will upgrade the battery pack. But I also have some HD servos that will need to have alternate power. Still haven't figured that one out yet. Is there a way to modify just the group of I/Os from 15 to 20 on the V.3 board with alternate power?

PRO
Synthiam
#9  

@Bret.Tallent I would not consider modifying the board. If you make a mistake, it's ruined. That'd be a pricey mistake:)

The additional power module should be available in a week

#11  

why not run power for your fan direct from battery. you can use a switch to trigger one relay to turn on ez b and another relay to turn on any other powered components, that way power is not coming from ez b and you will have a easy on off switch for your bot. i can give you directions and schematic for wiring. it may sound complicated but this is how we power pretty much anything in automotive customization.

PRO
Synthiam
#12  

@jstarne1 The relay will draw more current than the fan. The problem is he was running all of those peripherals off the 5 cell standard battery pack. That's only 1 amp, at max. I doubt it's even 1 amp with AA's. He'll be fine with a more powerful battery pack. I think the dudes that use lipo's know where it's at. They get 3-4 amps out of those things, and they're tiny and light.

We should start carrying more powerful battery solutions.

#13  

I got a Thunder Power RC LiPo from local RC shop 910mAh works great, size of two AAAs.

#14  

Using a transitor to turn stuff on and off is really easy.

  1. Get a TIP120 Darlington Transistor.
  2. Connect power to whatever you want to turn on and interrupt the ground with the "emitter" and "collector" from the transistor.
  3. Connect a wire from the PWM of one of the Digital ports to the "base" of the transistor.
  4. The circuit will be open (off) until you switch the digital port to HI which closes the circuit and turns your device on.

A TIP120 transistor from Radio Shack is less than $2.

PRO
Synthiam
#15  

User-inserted image

Maybe i should turn one of those into an ez-bit.. give it 4 or 5 channels. put a filter on it too.

#16  

@DJ -- I thought we had a deal! I'd answer the easy questions and you'd get more product and features out the door! :D

#17  

Sweet, I love all these Ideas! And thanks for the diagram!!!!!:D

#18  

So Upgrading my battery made all the difference. I am using the 6V 4.5ah battery for the omnibot. I tied the HD servos into the 6v power and everything is working wonderfully - ie. no dropped connections. I have noticed the external power supplied servos work better than the mini servos plugged solely onto the board. Those little servos flutter a lot and don't give full motion.

#19  

@dj I just tested a standard single pole double throw 6v and a 12v relay rated at 30 amps and they are drawing drawing 100ma that's 1/10th of an amp you must have used a household AC relay with 12v or somthing

#20  

Ok second test , I tried a 6-12v radioshack reed relay rated 10th amp and my meter shows 23ma. Less than 1/20th amp to power so its plenty efficient to use to connect accessories power on without passing through ezb at all. This way if you hardwire a camera , have ezb and servos direct to a power source you can use one switch and some basic reed relays and everything powers on or off with one switch.