rating like 3VDC or 6VDC? Normally the Power Relays with 10 to 15 amp c/o have 12VDC or 24VDC coil operating voltage. The question is can they be designed to operate on lower , even 3 VDC , coil rating.
If you get close enough to the relay makers - not at a retail catalog site - you will find relays with replaceable coils so you can mix and match the contact rating with the coil rating. Unfortunately, since the spring on the contacts remains the same, there has to be more windings and more amps to have a strong magnetic field to pull in the contacts Many many relays have 6 volt coils as shown here. http://documents.tycoelectronics.com/commerce/DocumentDelivery/DDEController?Action=srchrtrv&DocNm=1308242_K10&DocType=DS&DocLang=EN with other choices on this page http://relays.tycoelectronics.com/pnb.asp including 5 volts on this one http://documents.tycoelectronics.com/commerce/DocumentDelivery/DDEController?Action=srchrtrv&DocNm=1308242_KUKUP&DocType=DS&DocLang=EN
Hey there Dra...not only will they work but they do..lots of 24 will work at 12 and 12's at 9 and so forth...the reason that they chose those is the tap characteristics of of the power supply as a general standard has 6volt tube days and end taps of 12 ...the 24volt coil started showing up in mass in the 80's due to the increase in the micro electrification of the trucking bus sines which runs their diesel engines on 24vdc...Its sorta like my grandmother always told me to do it that way and I don't know why but I always did what my grandmother said....If you understand that then you understand the control power relay business..Now the IC voltages we created by some folks with ATT during their quest for the UNIX rush UC-Berkley on a defense funded project...Well have a good one...From the E...