Special Relays for low voltage circuit

This really sounds like a job for a solid state device. I could cludge you up something with zeners, transistors and op amps but I bet someone would jump in with an off the shelf solution so I will defer to the guys with the fat catalogs on their desk.

In article , snipped-for-privacy@hotmail.com says... | I am building a device that runs on regular batteries and I need to | use relays in it. Are there special relays for these sorts of low | voltages and currents? | | One of the relays needs to close a circuit once the pd in the main | circuit is above 2 or 3 volts (main circuit will reach 15 volts on | occasion). | | I need the other relay to close a switch once the pd gets above 12-14 | volts (I have a capaciter charging and I need it a circuit to close | when it reaches close to maximum charge). Is there a special relay | that I can get that will close a switch at the specified pd of 12-14 | volts. |

Operating at set voltages has never been the design function of a relay and the power consumption of relay coils does not mix very well with battery use.

Consider using an op-amp comparator circuit to detect the voltage (compare against a reference), then perhaps an analogue switch IC to act as the relay. Use of the latter item will depend on the voltage and current you intend to switch.