Low Voltage Sensing Relay?? -- HELP !!

[R. A. Piziali]

I have need of the following:

A relay that will handle a 15amp load and close at about 13.0-13.4vdc and
open at, say, about 12.7vdc. Is such a device available - if so where? OR what
can I put together to operate in such a manner??

The application: I want to AC power an RV refrigerator with an Inverter from
the vehicle DC charging system but automatically disconnect when RV battery is
not being charged, ie, to prevent powering Inverter from RV battery.

Ray
--\\\//
(o o)
*----------------------ooO-(_)-Ooo------------------------*
---- REMEMBER ----
+++++ Those who IGNORE history are doomed to repeat its mistakes!! +++++

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Government is not reason; it is not eloquence; it is force! Like fire,
it is a dangerous servant and a fearful master." -- George Washington
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
No God, No Peace!
Through Jesus,
Know God, Know Peace!
~~~~~~~~~~~~~~~~~~~~~

 

[Luhan Monat]

I have need of the following:

A relay that will handle a 15amp load and close at about 13.0-13.4vdc
and open at, say, about 12.7vdc. Is such a device available - if so
where? OR what can I put together to operate in such a manner??

The application: I want to AC power an RV refrigerator with an
Inverter from the vehicle DC charging system but automatically
disconnect when RV battery is not being charged, ie, to prevent powering
Inverter from RV battery.

Ray

Hi,

Easy solution: User a standard 'headlight relay' (30 amps) from any auto
supply store. Connect the contacts directly to the battery to power the
fridge. Connect the coil to the accessory circuit in the vehicle. This
will power the relay only when the engine is running.

 

[scada]

I have need of the following:

A relay that will handle a 15amp load and close at about 13.0-13.4vdc and
open at, say, about 12.7vdc. Is such a device available - if so where? OR what
can I put together to operate in such a manner??

The application: I want to AC power an RV refrigerator with an Inverter from
the vehicle DC charging system but automatically disconnect when RV battery is
not being charged, ie, to prevent powering Inverter from RV battery.

Ray
--
\\\//
(o o)
*----------------------ooO-(_)-Ooo------------------------*
---- REMEMBER ----
+++++ Those who IGNORE history are doomed to repeat its mistakes!! +++++

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Government is not reason; it is not eloquence; it is force! Like fire,
it is a dangerous servant and a fearful master." -- George Washington
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
No God, No Peace!
Through Jesus,
Know God, Know Peace!
~~~~~~~~~~~~~~~~~~~~~

Relays typically have a much lower drop out voltage than their pick up
voltage. A typical Automotive relay may, for instance, drop out at around 7
VDC. A simple alternative would be to connect a Heavy Duty Automotive Relay
(Air Cond, Horn, etc...) to the Fuse box Ignition circuit. The relay will
pull only when the key is on "Ignition" and not accessory.