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Other MidNite Electronics => WBjr => Topic started by: dgd on May 03, 2015, 11:13:12 PM

Title: Connectimg 2 Classics to one WBjr
Post by: dgd on May 03, 2015, 11:13:12 PM
Just wondering if this possible.
If one Classic is providing the power then could another Classic be connected via an opto isolator?
I assume its not a good idea to just wire direct to both
Reason is I want to implement Absorb EA on two Classics but do not want the serial ports used up by the follow me wiring

dgd
Title: Re: Connectimg 2 Classics to one WBjr
Post by: brad.midnite on May 04, 2015, 01:37:28 PM
It would involve a firmware change to The Classic, and I don't honestly know that it's worth the time-investment to do it.

It's not as simple as just isolating them somehow, or just allowing a second classic to listen only. The Classic sends a particular signal to the Whizbang Jr and it responds with a particular signal, it's a non-standard form of asynchronous serial. But the Classic is programmed to transmit-then-listen. For a second classic that never transmits, it would have to synchronize to the first Classic's request for information.

If I'm understanding your question you have two classics feeding the same battery bank, so you have a common system negative attached to a single Deltec shunt. Each 'Battery Negative' terminal on each classic leads to this same point on that shunt, correct?

If that's the case, buy a second Whizbang Jr. and some longer #8-32 screws and some additional aluminum spacers and stack two Whizbang Jr's on the same Deltec shunt. If the connection's nice and tight it should work.

-Brad
Title: Re: Connectimg 2 Classics to one WBjr
Post by: dgd on May 04, 2015, 02:03:53 PM
Ok, I didn't know there was two way Comms between the classic and WBjr, I thought the classic just listened. No matter I was just trying to avoid modbus  register writing to implement follow me in absorb to float charge States between two classics via web server
Thanks for replying
Dgd
Title: Re: Connectimg 2 Classics to one WBjr
Post by: Jacotenente on May 10, 2015, 07:57:30 AM
This is EXACTLY what I need to do...and was just going to split the purple wire and run it to both Classics. Glad I read this post. My second Classic is due in tomorrow...and it comes with a WBjr. I think it comes with spacers (if I remember correctly). So, you can stack two WBjr's atop each other on the shunt? Has anyone done this? Pictures? Thanks.

Chris