Special Relays for low voltage circuit

[Rupert]

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.

any help much appreciated.

Rupert

 

[Ian Stirling]

Rupert <roojai@hotmail.com> wrote:

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?

In general, yes, though you may have trouble finding ones to operate
at specific voltages.
You mention 12V, is this always available?

Using relays to act as voltage comparators isn't generally good practice.
The trip voltage may depend on orientation, vibration, as well as
how that voltage is approached.

There are many low power solid state solutions that can drive relays
if you need them to, and be vastly more accurate.
A more complete idea of what you are doing would be helpfull to make some
suggestions.

--
http://inquisitor.i.am/ | mailto:inquisitor@i.am | Ian Stirling.
---------------------------+-------------------------+--------------------------
Windows 2000, software for next millenia. <latin pun alert> - Ian Stirling.

 

roojai@hotmail.com (Rupert) wrote in message news:<71fc42d7.0309090806.12a386b7@posting.google.com>...

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.

any help much appreciated.

Rupert

Howdy Rupert,

If space and costs allow, I would use a small off the shelf dc-dc
convertor package to provide the relay supply, and choose a common
relay type to use throughout the design.


regards
Alastair