robo rad
Resolved by Dave Schulpius!
My Rad 1.0 project robot is nearly completed but have one serious question about causing power damage to either the 4 wire H bridge pwm or the EZB_4. After completion of successfully wire soldering to original rad 6 volt motors to H Bridge which is sharing the same dual 7.2 Nimh battery packs with Ezb_4, I also rewired the original Rad wires and circuit board back to original so I can keep the original radio control working with it's own original 6 volt nickel battery pack.Now the wires going to both rad motors are shared with H bridge at 5 volts (button is pressed on h bridge to use it's own 5 volt regulator and not EZB 7.4 power) Now I am scared to ever run both RC original rad system with new EZB system together at same time.So far I have tried running with 1 system at a time, I simply remove old Rad 6 volt battery and leave original switch off while running EZB.Then to regain old rc control I simply disconnect EZB/h bridge battery packs and put in old Rad 6 volt battery and turn on switch,works great again with. Old radio control......So now my question is about motor leakage feedback voltage damage to H bridge,would this happen if I ran old system and new EZB system together with all batteries connected at same time? Or would I get some benefit with extra battery power from original rad battery 6 volts?I am afraid to try that but may consider adding a new switch to just add old 6 volt battery in parallel wiring to the h bridge/EZB battery packs,any advice greatly appreciated,hope my question makes sense the way I described it confused
I had a hard time understanding your wiring set up. However if you're worried about one voltage source backfeeding into another you can use blocking diodes instead of manual switches. You need to size them to how many amp your motors and devices are pulling from the power sources.
Ah yes I should have simplified the question so,basically yes both the rad circuit board and the EZB/h bridge are all wired to the same 2 motors and was worried what will happen if I run all the batteries at the same time so If My laptop script moves the robot to a dangerous area I can simply use the old Rad radio control to back it up out of danger.As a panic button. Diodes are a great idea as current can only go one way,thanks!
Thanks Dave, give credit to you for the solution!
Thanks for the credit. One more thing you need to consider. If you have two power source tied together you need to pay attention to how they are wired. One way, parallel, will supply more amps. Second way, series, will give more voltage and amps. You don't want to send up to twice the voltage of the motors ratings. It's really not a good practice. More supplied amps are always a good thing. Remember, motors, lights and devices eat amps. Power sources supply amps. More amps available (up to 20% of total needed by your devices) the better.
Yes I actually did double my robot running time by using 2 ---7.2 battery packs and wondering if I add 2 more of my old Rad 6 volt packs in parallel ,to get the robot enough power to run 6 hours with on and off roaming.Or just buy one really powerful battery to run everything.How many Amps can the EZB handle?I will research that before buying any more powerful batteries.
The ezb has a 20 amp fuse in the power base. I'd feel good about pulling 20 amps through the power pins of the digital ports.
Oh yes of course,forgot about that fuse feature,thanks!