----- Original Message -----
Sent: Monday, June 06, 2005 5:12 PM
Subject: [FlyRotary] Re: EC2 dual power
feeds
Finally got around to
seeing what it would take to retrofit separate power feeds to the two
controllers. It can be done but obviously it was not high on my list of
concerns. But, if this is bothering any builders, I can do this
rework for a cost of $110.00 + shipping.
Hi
Tracy,
I wasn't trying to guilt you
into this, particularly since it's been so ineffective with the
datalogging request :-)
So with this mod, would pins 33
and 34 be split internally, so that one goes to A, and the
other to B?
How much other circuitry is shared? Obviously,
all the control panel functions have to be shared, so would that be
powered by both controllers, or just one or the other? If the
control panel lost power, would the controller just continue with it's
last known settings?
I presume there's some switching inside for all the
various wires that are used by the EC-2 for input and output
functions. What would power that
circuitry?
I'm sure there are factors that I haven't even
thought of, which make this dual power feed a can of worms. In
my post, I really wasn't picking on the EC-2, but rather saying that I agreed
it was probably as good as it can get in one unit. If you
don't think the dual power feed adds significantly to
the safety of the unit, then I'm going to say that's good
enough for me.
I've actually thought of using two MicroTech
controllers, but haven't been able to figure out exactly how you'd make the
switch between the two. At some point, there has to be something common
between the two, even if it's the switching circuitry to chose one or the
other. Best I've been able to come up with was to mount the
boxes in reach, and then physically swap the main cable if you
need to switch controller. Clearly, that would suck in a crisis
:-)
Thanks very much for the offer to make this
mod. Depending on the answer to some of the above, I'll decide if it
will ease my mind any.
Cheers,
Rusty (trying to remember if I actually ran two wires
to the connector)
In order to have truly redundant EC2s would require a
3rd CPU to monitor the two controllers and
automatically switch the failed unit off. Then what is going to monitor
the 3rd computer?
Wendell