Kevin Trombley via EV wrote:
Thanks, for the information. I have been researching & looking at a
lot of different Reed Relays.

Hi Kevin,

A reed relay is just a small relay. Their contacts are sealed inside
glass, and good because the contacts can never get corroded or dirty.
This makes them especially good for "dry circuit" applications, where
the current or voltage are so low that normal relays can suffer
from contact corrosion problems.

I understand, a 12V Reed relay coil is needed to be able to be
operated, by the ignition of an automobile's electrical system & that
the switched current is only going to be like 20ma. But, there are so
many of different voltages, capacities etc. I also, noticed that many
even have different ohm rating's listed. Could you recommend or point
me toward a specific relay for this situation or at least what
details to look for?

An easy way is to go to and search for "reed relay". It will be the 2nd item in the "Relays" list. Click "in stock", "12vdc" coil voltage, and "DPST 2 form A" contact form. That will cut it down to "only" 15 to choose from. :-)

All of them are rated to switch 100vdc or more. You will have two contacts in series, so each one will only see half your pack voltage. Thus a 100vdc part is still good for switching up to a 200vdc pack. Any will work, but you might as well use the cheapest one (HE108-ND, $2.21 each)

It may be a dumb question but, could a (12V - 1.5Kohm) Reed Relay be
used as, or in place of, the 1.5Kohm resistor & as a switch?

No. The relay's contacts go in series with the resistors. The relay's coil get connected to some point in your 12vdc circuit that will be on when you want the Batt-Bridge to work.

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and a sterner sense of justice than we do. -- Wendell Berry
Lee Hart, 814 8th Ave N, Sartell MN 56377,
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