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configuration h</title></head><body>
<div>End results are another thing.</div>
<div><br></div>
<div>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.</div>
<div><br></div>
<div>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.</div>
<div><br></div>
<div>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.</div>
<div><br></div>
<div>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.</div>
<div><br></div>
<div>cheers</div>
<div><br></div>
<div>Hugh Piggott</div>
<div><br></div>
<blockquote type="cite" cite>Sorry, bad terminology on my part.<br>
<br>
I was wishing for software that could do more than "set the relay
driver" to respond to programmed parameters.<br>
<br>
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.<br>
<br>
Jolliness,<br>
<br>
Mick Abraham, Proprietor<br>
<a href="http://www.abrahamsolar.com">www.abrahamsolar.com</a><br>
<br>
Voice: 970-731-4675<br>
</blockquote>
<blockquote type="cite" cite>On Thu, Apr 14, 2011 at 1:53 AM, Hugh <<a
href="mailto:hugh@scoraigwind.co.uk">hugh@scoraigwind.co.uk</a>>
wrote:<br>
<blockquote>At 10:30 -0600 13/4/11, Mick Abraham wrote:<br>
<blockquote>I wish that M-star had some "wizard type"
Windows software that could lead one through the setup.<br>
</blockquote>
</blockquote>
<blockquote><br></blockquote>
<blockquote>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.<br>
<a
href="http://www.morningstarcorp.com/en/support/item.cfm?ItemId=400"
>http://www.morningstarcorp.com/en/support/item.cfm?ItemId=400</a><br>
Seems pretty self-explanatory to me but the manual is there for
reference too.<br>
<br>
I did not know that there was any other way to set them up.<br>
<font color="#888888">--<br>
Hugh Piggott<br>
<br>
Scoraig<br>
</font><a href="http://www.scoraigwind.co.uk"><font
color="#888888">http://www.scoraigwind.co.uk</font></a></blockquote>
<blockquote><br>
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<div><br></div>
<div><br></div>
<x-sigsep><pre>--
</pre></x-sigsep>
<div>Hugh Piggott<br>
<br>
Scoraig<br>
http://www.scoraigwind.co.uk</div>
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