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Drake,<br>
<br>
The Morningstar relay driver doesn't output voltage; it can sink
current or measure voltage. Normally the outputs are wired to the
same source that powers the relay driver - it is the power source
that is putting out voltage. It shouldn't be a problem to run a
12-volt relay from a separate 12-volt source (or 12 volts derived
from the 48-volt source) as long as the ground of the separate
source is common with the relay driver ground. Simply add a 48V to
12V converter to the project and you can operate one to four 12-volt
relays, or a mix with some being 12 and others being 48 volts.<br>
<br>
Kent Osterberg<br>
Blue Mountain Solar
<p><br>
</p>
<div class="moz-cite-prefix">On 7/21/2026 6:35 AM, Drake Chamberlin
via RE-wrenches wrote:<br>
</div>
<blockquote type="cite" cite="mid:ef013e4fdea1a4eb3c53f8f532e2c764@redwoodalliance.org">
<div class="pre" style="margin: 0; padding: 0; font-family: monospace"><span style="font-size: 12pt;">Hello,</span></div>
<div class="pre" style="margin: 0; padding: 0; font-family: monospace"> </div>
<div class="pre" style="margin: 0; padding: 0; font-family: monospace"><span style="font-size: 12pt;">The Morningstar relay driver is a
great device. It can measure 48VDC nominal and operate relays
based on the measured voltage. The problem is that, if it is
measuring 48VDC nominal, it outputs the same. </span>
<div class="pre" style="margin: 0; padding: 0; font-family: monospace"> </div>
</div>
<div class="pre" style="margin: 0; padding: 0; font-family: monospace">
<div><span style="font-size: 12pt;">Is there anything besides a
charge controller that can measure 48 VDC nominal and put
out a small 12VDC current? The 12VDC output of an Outback or
Midnite charge control is perfect. </span></div>
<div> </div>
<div><span style="font-size: 12pt;">If a relay driver, with
several channels, could do this, it would be a very useful
device. Does anything like this exist?</span></div>
<div> </div>
<div><span style="font-size: 12pt;">Thanks,</span></div>
<div> </div>
<div><span style="font-size: 12pt;">Drake </span></div>
<div> </div>
<div>
<p><em>Drake Chamberlin</em></p>
<p><em>Athens Electric LLC</em></p>
<p><em>Ohio Electrical Contractor’s License 44810</em></p>
<p><em>NABCEP Certified PV Installation Professional</em></p>
</div>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
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