our company want to produce an adjustable current limiting device to
sell with our linear actuators. what we need is the circuit designing.
here is the spec for the black box.
1. input voltage 12vdc 1-10 amps (2 wires)
2. output voltage 1-5 amps (2 wires that will go directly to the actuator)
3. must work in reverse polarity mode
4. adjustable current sensing for both polarities 1-10 amps using a
variable resistor, so 2 of these
The over current device needs 2 modes
1. once the system has ran for 1 second or more but then the overload
kicks in (the actuator is stalled) then the system needs to stop the
actuator and reverse it. (imajine an electronic gate opening device
where the car gets int he way)
2. upon starting the actuator and the system detects something in the
way (overload kicks it) then the system needs to just stop until the
system reverses polarity to reset it. This is for a situation where
the gate is fully opne or fully closed but there is something in the
way to prevent it from opening or closing like snow etc. This can work
using a time based system where if the circuit is operated for less
than 1 second and detects a stall then it uses this operation, if
after 1 second then it goes to another operation (1)

this device will be used with our linear actuators where they are used
for many applications like opening gaated etc and they need a safety
feature.

the result of this is to have a complete electrical drawing schematic
that we can hand to an electrical company to make it up for us. It
must be 2 wires inand 2 out and use low cost chips.