[RE-wrenches] Morningstar relay driver configuration help

[Hugh]

End results are another thing.

I was recently trying to program two RDs to operate six 500W heaters 
(I needed to use a channel on each as inputs since the battery 
nominal voltage is 108 VDC).  The heaters work off a 5kW inverter.  I 
wanted to keep the battery from exceeding 126 volts since it is a 
sealed battery.

I tried two basic strategies: one based on different (close) voltage 
thresholds, and one based on time delays.  It proved very difficult 
to prevent the system from becoming unstable, with heaters coming on 
in avalanches and high swings in voltage (where I used different 
thresholds) or having to put in rather large delays (using delays 
rather than voltages to discriminate loads) and having large voltage 
swings due to these delays.

Although I have used RDs for quite a few other applications with some 
satisfaction, I am not really happy with the way these worked for 
fast changing battery voltages (3kw wind turbine) and discrete AC 
dump loads on the inverter.  In the end the sampling rate is maybe 
not fast enough, and so there is insufficient discrimination between 
different voltage levels during a rapid rise, resulting in avalanche 
behaviour and thence wild swings in voltage.

Not sure how clever a wizard would have to be to figure out all of 
the circumstances in such cases but it does not take long to load and 
test a new configuration on site in good test conditions.  A few more 
example configurations would be helpful.

cheers

Hugh Piggott

>Sorry, bad terminology on my part.
>
>I was wishing for software that could do more than "set the relay 
>driver" to respond to programmed parameters.
>
>If a training application could instruct the human on a wide range 
>of "end results", relay driver action that would be appropriate for 
>each one, and the action of external components which would help 
>meet those results, etc...that's more of what I was wishing for.
>
>Jolliness,
>
>Mick Abraham, Proprietor
><http://www.abrahamsolar.com>www.abrahamsolar.com
>
>Voice: 970-731-4675
>
>On Thu, Apr 14, 2011 at 1:53 AM, Hugh 
><<mailto:hugh at scoraigwind.co.uk>hugh at scoraigwind.co.uk> wrote:
>
>At 10:30 -0600 13/4/11, Mick Abraham wrote:
>
>I wish that M-star had some "wizard type" Windows software that 
>could lead one through the setup.
>
>
>The wizard is the only way I know of for setting it up.  I use 'MS 
>view' and choose the relay driver wizard.  I see they have a new 
>edition out last month so I will download and try that.
><http://www.morningstarcorp.com/en/support/item.cfm?ItemId=400>http://www.morningstarcorp.com/en/support/item.cfm?ItemId=400
>Seems pretty self-explanatory to me but the manual is there for reference too.
>
>I did not know that there was any other way to set them up.
>--
>Hugh Piggott
>
>Scoraig
><http://www.scoraigwind.co.uk>http://www.scoraigwind.co.uk
>
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-- 
Hugh Piggott

Scoraig
http://www.scoraigwind.co.uk
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